東北大学研究者紹介 - 石徹白　晃治

顔写真

イシドシロ　コウジ

石徹白　晃治

Koji Ishidoshiro

所属

ニュートリノ科学研究センター

職名

准教授

学位

博士（理学）（東京大学）
修士（理学）（東京大学）

researchmap

https://researchmap.jp/7000002208

J-GLOBAL ID

201201005181180035

経歴 3

2020年1月～継続中

東北大学　ニュートリノ科学研究センター　准教授
2012年4月～ 2019年12月

東北大学　ニュートリノ科学研究センター　助教
2010年4月～ 2012年3月

高エネルギー加速器研究機構　研究員

学歴 2

東京大学　理学系研究科

2004年4月～ 2010年3月
筑波大学　第一学群　自然学類

2000年4月～ 2004年3月

委員歴 6

宇宙線研究者会議　実行委員

2022年4月～ 2023年3月
宇宙線研究者会議　総務

2019年4月～ 2020年3月
宇宙線研究者会議　書記

2018年4月～ 2019年3月
宇宙線宇宙物理領域　領域委員

2016年10月～ 2018年9月
日本物理学会　(宇宙線宇宙物理領域)領域運営委員

2016年10月～ 2017年9月
日本物理学会　(宇宙線宇宙物理領域)領域運営委員

2016年10月～ 2017年9月

︎全件表示 ︎最初の5件までを表示

所属学協会 2

日本天文学会
日本物理学会

研究キーワード 4

超伝導検出器
暗黒物質
素粒子物理学
ニュートリノ

研究分野 1

自然科学一般 / 素粒子、原子核、宇宙線、宇宙物理にする実験 /

受賞 1

日本物理学会若手奨励賞

2012年3月　日本物理学会

論文 79

Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, S. Hayashida, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, M. Koga, M. Kurasawa, N. Maemura, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, D. Chernyak, A. Kozlov, K. Z. Nakamura, S. Yoshida, Y. Takemoto, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, J. Smolsky, Z. Fu, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, S. Dell’Oro, T. O’Donnell, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, A. Li, H. Song

Physical Review Letters　130　(5)　2023年1月30日
出版者・発行元：American Physical Society (APS)
DOI： 10.1103/physrevlett.130.051801 　

ISSN：0031-9007

eISSN：1079-7114

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The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νββ) decay half-life in Xe136 using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of Xe136. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νββ decay half-life of T1/20ν>2.3×1026 yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.
Theoretical Prediction of Presupernova Neutrinos and Their Detection 査読有り

C. Kato, K. Ishidoshiro, T. Yoshida

Annual Review of Nuclear and Particle Science　70　(1)　121-145　2020年10月19日
出版者・発行元：Annual Reviews
DOI： 10.1146/annurev-nucl-040620-021320 　

ISSN：0163-8998

eISSN：1545-4134

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More than 30 years have passed since the successful detection of supernova (SN) neutrinos from SN 1987A. In the last few decades, remarkable progress has been made in neutrino detection techniques, through which it may be possible to detect neutrinos from a new source, presupernova (pre-SN) neutrinos. They are emitted from a massive star prior to core bounce. Because neutrinos escape from the core freely, they carry information about the stellar physics directly. Pre-SN neutrinos may play an important role in verifying our understanding of stellar evolution for massive stars. Observation of pre-SN neutrinos, moreover, may serve as an alarm regarding an SN explosion a few days in advance if the progenitor is located in our vicinity, enabling us to observe the next galactic SN. In this review, we summarize the current status of pre-SN neutrino studies from both the theoretical and observational points of view.
KamLAND SENSITIVITY TO NEUTRINOS FROM PRE-SUPERNOVA STARS 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, A. Piepke, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, J. G. Learned, J. Maricic, S. Matsuno, M. Sakai, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

ASTROPHYSICAL JOURNAL　818　(1)　91　2016年2月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.3847/0004-637X/818/1/91 　

ISSN：0004-637X

eISSN：1538-4357

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In the late stages of nuclear burning for massive stars (M > 8 M-circle dot), the production of neutrino-antineutrino pairs through various processes becomes the dominant stellar cooling mechanism. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron antineutrinos exceeds the energy threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of 25 M-circle dot at a distance less than 690 pc with 3 sigma significance before the supernova. This limit is dependent on the neutrino mass ordering and background levels. KamLAND takes data continuously and can provide a supernova alert to the community.
RFSoC-based front-end electronics for pulse detection

S.N. Axani, S. Futagi, M. Garcia, C. Grant, K. Hosokawa, S. Ieki, K. Inoue, K. Ishidoshiro, N. Kawada, Y. Matsumoto, T. Nakahata, K. Nakamura, R. Shouji, H. Song, L.A. Winslow

Journal of Instrumentation　19　(03)　P03013-P03013　2024年3月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1748-0221/19/03/p03013 　

eISSN：1748-0221

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Abstract Radiation measurement relies on pulse detection, which can be performed using various configurations of high-speed analog-to-digital converters (ADCs) and field-programmable gate arrays (FPGAs). For optimal power consumption, design simplicity, system flexibility, and the availability of DSP slices, we consider the Radio Frequency System-on-Chip (RFSoC) to be a more suitable option than traditional setups. To this end, we have developed custom RFSoC-based electronics and verified its feasibility. The ADCs on RFSoC exhibit a flat frequency response of 1–125 MHz. The root-mean-square (RMS) noise level is 2.1 ADC without any digital signal processing. The digital signal processing improves the RMS noise level to 0.8 ADC (input equivalent 40 μVrms). Baseline correction via digital signal processing can effectively prevent photomultiplier overshoot after a large pulse. Crosstalk between all channels is less than -55 dB. The measured data transfer speed can support up to 32 kHz trigger rates (corresponding to 750 Mbps). Overall, our RFSoC-based electronics are highly suitable for pulse detection, and after some modifications, they will be employed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND).
Application of gamma Transition-Edge-Sensor (TES) to 112Sn two-neutrino double electron capture search

Koichi Ichimura, Koji Ishidoshiro, Azusa Gando, Kaori Hattori, Takahiro Kikuchi, Hirotake Yamamori, Shinya Yamada, Tadafumi Kishimoto

Proceedings of XVIII International Conference on Topics in Astroparticle and Underground Physics — PoS(TAUP2023)　2024年1月15日
出版者・発行元：Sissa Medialab
DOI： 10.22323/1.441.0267 　
Measurement of cosmic-ray muon spallation products in a xenon-loaded liquid scintillator with KamLAND

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, M. Koga, M. Kurasawa, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, Z. Fu, J. Smolsky, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, S. Dell'Oro, T. O'Donnell, J. A. Detwiler, S. Enomoto, M. P. Decowski, K. M. Weerman, C. Grant, A. Li, H. Song

Physical Review C　107　(5)　2023年5月22日
出版者・発行元：American Physical Society (APS)
DOI： 10.1103/physrevc.107.054612 　

ISSN：2469-9985

eISSN：2469-9993
First measurement of the strange axial coupling constant using neutral-current quasielastic interactions of atmospheric neutrinos at KamLAND

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, M. Koga, M. Kurasawa, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, Z. Fu, J. Smolsky, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, A. Li, H. Song, S. Dell’Oro, T. O’Donnell

Physical Review D　107　(7)　2023年4月19日
出版者・発行元：American Physical Society (APS)
DOI： 10.1103/physrevd.107.072006 　

ISSN：2470-0010

eISSN：2470-0029
A study of self-vetoing balloon vessel for liquid-scintillator detectors

S. Obara, Y. Gando, S. Ieki, H. Ikeda, K. Ishidoshiro, R. Nakamura

Journal of Physics: Conference Series　2374　(1)　012111-012111　2022年11月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/2374/1/012111 　

ISSN：1742-6588

eISSN：1742-6596

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KamLAND-Zen searches for neutrinoless double-beta decay with an ultra-pure liquid-scintillator (LS) filled with a custom-made clean nylon balloon. The primary backgrounds are radioactive impurities such as uranium and thorium series. To reduce them, we studied a self-vetoing balloon-shaped vessel for a future upgrade program, “KamLAND2-Zen”. We selected Polyethylene-Naphthalate (PEN) film which emit fluorescent light and performed the feasibility studies. Owing to its scintillation properties, 214Bi background could be identified in the KamLAND2-Zen. Moreover, thanks to the different waveforms between the LS and the PEN, we can apply the pulse-shape-discrimination for 212Bi-Po pileup background. We evaluated its background rejection efficiency as more than 90%. Resulting from these studies, it is possible to remove restrictions on fiducial volume in KamLAND2-Zen.
Progress of Kinetic Inductance Detectors on Calcium Fluoride for Astroparticle physics

Zulfakri Mohamad, Koji Ishidoshiro, Yasuhiro Kishimoto, Satoru Mima, Tohru Taino, Keishi Hosokawa, Kosuke Nakamura, Minori Eizuka, Ryota Ito, Hiroki Kawamura

Journal of Physics: Conference Series　2374　(1)　012026-012026　2022年11月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/2374/1/012026 　

ISSN：1742-6588

eISSN：1742-6596

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Kinetic Inductance Detector (KID) is an exciting device that promises high sensitivity to photons from submillimeter waves to gamma-rays with large format arrays. The KID consists of a superconductor thin film microwave resonator combined with a transmission line. When energy accumulates, Cooper pairs in the superconductor films are broken. Then quasiparticles are produced. This change increases the kinetic inductance in the resonant circuits and can be monitored by the transmission line. We propose that Lumped Element KID (LEKID) is implemented on Calcium Fluoride (CaF2) substrate for next-generation astroparticle experiments. 48Ca is one of the double-beta decay nuclei, and 19F is sensitive to spin-dependent elastic scattering with dark matter. The LEKID on CaF2 can be cooled to 15mK using a dilution refrigerator. At this stage, the quality factors of the LEKID are about 500×103, and measurement for particle detection using 241Am particle irradiation is also demonstrated at this low temperature.
Concept of KamLAND2 DAQ system

S. Ieki, S. Asami, S. Axani, S. Futagi, K. Hosokawa, K. Ishidoshiro, T. Nakahata, K. Nakamura

Journal of Physics: Conference Series　2374　(1)　012104-012104　2022年11月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/2374/1/012104 　

ISSN：1742-6588

eISSN：1742-6596

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The KamLAND-Zen experiment is searching for neutrinoless double-beta decay of 136Xe. We are preparing for the upgrade of the KamLAND detector, KamLAND2. It is designed to improve the discrimination power of two-neutrino double-beta decay and cosmic-ray muon spallation backgrounds. Data acquisition of all neutrino events from nearby supernova is also an important issue of the KamLAND2 experiment and the data rate is a key factor to design a new DAQ system. High speed sampling will be realized with RFSoC on the front-end electronics. Data is read out from FEE to DAQ computers via 10 GbE, and FairMQ is one of the candidates for KamLAND2 DAQ software. In the KamLAND DAQ, the whole trigger system is implemented in hardware, while the KamLAND2 DAQ adopts hardware trigger for photon detection and software trigger to extract physics events. A simulation study of the software trigger is proceeding in order to detect low energy events using timing and charge information.
KamLAND’s search for correlated low-energy electron antineutrinos with astrophysical neutrinos from IceCube

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, T. Kinoshita, M. Koga, M. Kurasawa, N. Maemura, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, H. Watanabe, Y. Yoshida, S. Obara, A.K. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B.E. Berger, B.K. Fujikawa, J.G. Learned, J. Maricic, S.N. Axani, J. Smolsky, J. Lertprasertpong, L.A. Winslow, Z. Fu, J. Ouellet, Y. Efremenko, H.J. Karwowski, D.M. Markoff, W. Tornow, A. Li, J.A. Detwiler, S. Enomoto, M.P. Decowski, C. Grant, H. Song, T. O’Donnell, S. Dell’Oro

Astroparticle Physics　143　102758-102758　2022年10月
出版者・発行元：Elsevier BV
DOI： 10.1016/j.astropartphys.2022.102758 　

ISSN：0927-6505

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We report the results of a search for MeV-scale astrophysical neutrinos in KamLAND presented as an excess in the number of coincident neutrino interactions associated with the publicly available high-energy neutrino datasets from the IceCube Neutrino Observatory. We find no statistically significant excess in the number of observed low-energy electron antineutrinos in KamLAND, given a coincidence time window of ±500 s, ±1,000 s, ±3,600 s, and ±10,000 s around each of the IceCube neutrinos. We use this observation to present limits from 1.8 MeV to 100 MeV on the electron antineutrino fluence, assuming a mono-energetic flux. We then compare the results to several astrophysical measurements performed by IceCube and place a limit at the 90% confidence level on the electron antineutrino isotropic thermal luminosity from the TXS 0506+056 blazar.
Abundances of Uranium and Thorium Elements in Earth Estimated by Geoneutrino Spectroscopy 査読有り

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, M. Koga, M. Kurasawa, N. Maemura, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, Y. Shirahata, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, Z. Fu, J. Smolsky, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, H. Song, T. O’Donnell, S. Dell’Oro

Geophysical Research Letters　49　(16)　2022年8月28日
出版者・発行元：American Geophysical Union (AGU)
DOI： 10.1029/2022gl099566 　

ISSN：0094-8276

eISSN：1944-8007

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The decay of the primordial isotopes 238U, 235U, 232Th, and 40K has contributed to the terrestrial heat budget throughout the Earth's history. Hence, the individual abundance of those isotopes are key parameters in reconstructing contemporary Earth models. The geoneutrinos produced by the radioactive decays of uranium and thorium have been observed with the Kamioka Liquid-Scintillator Antineutrino Detector (KamLAND). Those measurements have been improved with more than 18-year observation time, and improvement in detector background levels mainly with an 8-year nearly reactor-free period, which now permit spectroscopy with geoneutrinos. Our results yield the first constraint on both uranium and thorium heat contributions. The KamLAND result is consistent with geochemical estimations based on elemental abundances of chondritic meteorites and mantle peridotites. The High-Q model is disfavored at 99.76% C.L. and a fully radiogenic model is excluded at 5.2σ assuming a homogeneous heat producing element distribution in the mantle.
Search for Supernova Neutrinos and Constraint on the Galactic Star Formation Rate with the KamLAND Data

S. Abe, S. Asami, M. Eizuka, S. Futagi, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, M. Koga, M. Kurasawa, N. Maemura, T. Mitsui, H. Miyake, T. Nakahata, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, H. Watanabe, Y. Yoshida, S. Obara, A. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, K. Kotera, Y. Urano, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, L. A. Winslow, Z. Fu, J. Smolsky, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, H. Song, T. O’Donnell, S. Dell’Oro

The Astrophysical Journal　934　(1)　85-85　2022年7月1日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/ac7a3f 　

ISSN：0004-637X

eISSN：1538-4357

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Abstract We present the results of a search for core-collapse supernova neutrinos, using long-term KamLAND data from 2002 March 9 to 2020 April 25. We focus on the electron antineutrinos emitted from supernovae in the energy range of 1.8–111 MeV. Supernovae will make a neutrino event cluster with the duration of ∼10 s in the KamLAND data. We find no neutrino clusters and give the upper limit on the supernova rate to be 0.15 yr−1 with a 90% confidence level. The detectable range, which corresponds to a >95% detection probability, is 40–59 kpc and 65–81 kpc for core-collapse supernovae and failed core-collapse supernovae, respectively. This paper proposes to convert the supernova rate obtained by the neutrino observation to the Galactic star formation rate. Assuming a modified Salpeter-type initial mass function, the upper limit on the Galactic star formation rate is <(17.5–22.7) M⊙ yr−1 with a 90% confidence level.
A Search for Correlated Low-energy Electron Antineutrinos in KamLAND with Gamma-Ray Bursts 査読有り

S. Abe, S. Asami, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, T. Kinoshita, M. Koga, N. Maemura, T. Mitsui, H. Miyake, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, M. Eizuka, M. Kurasawa, T. Nakahata, S. Futagi, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, S. Yoshida, S. Umehara, K. Fushimi, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, J. Smolsky, C. Laber-Smith, L. A. Winslow, Z. Fu, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, H. Song, T. O’Donnell, S. Dell’Oro

The Astrophysical Journal　927　(1)　69-69　2022年3月1日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/ac4e7e 　

ISSN：0004-637X

eISSN：1538-4357

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Abstract We present the results of a time-coincident event search for low-energy electron antineutrinos in the KamLAND detector with gamma-ray bursts (GRBs) from the Gamma-ray Coordinates Network and Fermi Gamma-ray Burst Monitor. Using a variable coincidence time window of ±500 s plus the duration of each GRB, no statistically significant excess above the background is observed. We place the world’s most stringent 90% confidence level upper limit on the electron antineutrino fluence below 17.5 MeV. Assuming a Fermi–Dirac neutrino energy spectrum from the GRB source, we use the available redshift data to constrain the electron antineutrino luminosity and effective temperature.
Limits on Astrophysical Antineutrinos with the KamLAND Experiment 査読有り

S. Abe, S. Asami, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, S. Hayashida, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, T. Kinoshita, M. Koga, N. Maemura, T. Mitsui, H. Miyake, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, Y. Shirahata, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, Y. Wada, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, A. Kozlov, D. Chernyak, Y. Takemoto, S. Yoshida, S. Umehara, K. Fushimi, S. Hirata, K. Z. Nakamura, M. Yoshida, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, L. A. Winslow, Z. Fu, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, T. O’Donnell, S. Dell’Oro

The Astrophysical Journal　925　(1)　14-14　2022年1月1日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/ac32c1 　

ISSN：0004-637X

eISSN：1538-4357

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Abstract We report on a search for electron antineutrinos (${\bar{\nu } }_{e}$) from astrophysical sources in the neutrino energy range 8.3–30.8 MeV with the KamLAND detector. In an exposure of 6.72 kton-year of the liquid scintillator, we observe 18 candidate events via the inverse beta decay reaction. Although there is a large background uncertainty from neutral current atmospheric neutrino interactions, we find no significant excess over background model predictions. Assuming several supernova relic neutrino spectra, we give upper flux limits of 60–110 cm−2 s−1 (90% confidence level, CL) in the analysis range and present a model-independent flux. We also set limits on the annihilation rates for light dark matter pairs to neutrino pairs. These data improve on the upper probability limit of 8B solar neutrinos converting into ${\bar{\nu } }_{e}$, ${P}_{ { \nu }_{e}\to {\bar{\nu } }_{e } }\lt 3.5\times {10}^{-5}$ (90% CL) assuming an undistorted ${\bar{\nu } }_{e}$ shape. This corresponds to a solar ${\bar{\nu } }_{e}$ flux of 60 cm−2 s−1 (90% CL) in the analysis energy range.
Search for Solar Flare Neutrinos with the KamLAND Detector 査読有り

S. Abe, S. Asami, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, S. Hayashida, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, T. Kinoshita, M. Koga, N. Maemura, T. Mitsui, H. Miyake, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, Y. Wada, H. Watanabe, Y. Yoshida, S. Obara, A. K. Ichikawa, A. Kozlov, D. Chernyak, Y. Takemoto, S. Yoshida, S. Umehara, K. Fushimi, K. Z. Nakamura, M. Yoshida, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, L. A. Winslow, Z. Fu, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, T. O’Donnell, S. Dell’Oro

The Astrophysical Journal　924　(2)　103-103　2022年1月1日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/ac35d1 　

ISSN：0004-637X

eISSN：1538-4357

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<title>Abstract</title> We report the result of a search for neutrinos in coincidence with solar flares from the GOES flare database. The search was performed on a 10.8 kton-year exposure of KamLAND collected from 2002 to 2019. This large exposure allows us to explore previously unconstrained parameter space for solar flare neutrinos. We found no statistical excess of neutrinos and established 90% confidence level upper limits of 8.4 × 107 cm−2 (3.0 × 109 cm−2) on the electron antineutrino (electron neutrino) fluence at 20 MeV normalized to the X12 flare, assuming that the neutrino fluence is proportional to the X-ray intensity.
Supernova Neutrino Burst Search at KamLAND

M Eizuka, K Ishidoshiro, S Obara

Journal of Physics: Conference Series　2156　(1)　012195-012195　2021年12月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/2156/1/012195 　

ISSN：1742-6588

eISSN：1742-6596

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<title>Abstract</title> We report a result of supernova neutrino burst search at KamLAND in a neutrino energy range of 1.8–111 MeV via the inverse-beta decay (IBD). The search was performed using data from 2002 March 9th to 2020 July 17th, and the corresponding livetime is 5001.21 days. We searched for two or more sequential IBD events within 10 s as a supernova neutrino burst candidate. The dominant background is the accidental cluster of 2 or more IBD events caused by neutrinos from other sources, though, which are estimated to be almost negligible. We evaluated detectable ranges for some emitted supernova neutrino burst models. The conservative detectable ranges are 38kpc for core-collapse supernova (ccSN) and 42kpc for failed ccSN. We found no significant supernova neutrino burst events and set a 90% upper limit on the supernova neutrino detection rate in KamLAND as 0.178 burst/yr.
Search for Supernova Relic Neutrinos at KamLAND

S Obara, S Ieki, K Ishidoshiro, T Mitsui, H Watanabe, M P Decowski

Journal of Physics: Conference Series　2156　(1)　012138-012138　2021年12月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/2156/1/012138 　

ISSN：1742-6588

eISSN：1742-6596

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<title>Abstract</title> We report a search for electron antineutrinos at KamLAND with an 8.3−30.8 MeV energy range via the inverse beta decay. In 6.72 kton-yr of KamLAND data, we found 18 neutrino candidates and no significant excess over estimated backgrounds. From data interpretation, with the assumption of some supernova relic neutrino spectrum predictions, we give upper flux limits of 60−110 cm−2 s−1 (90% CL) in the analysis range and present a model-independent flux. These upper limits are the most stringent for 8−13 MeV region. We also improve on the upper probability limit of 8B solar neutrinos converting into antineutrinos via the Resonant Spin Flavor Precession with the neutrino magnetic moment. Besides, we could set limits on the annihilation cross-section for light dark matter pairs to neutrino pairs.
The nylon balloon for xenon loaded liquid scintillator in KamLAND-Zen 800 neutrinoless double-beta decay search experiment 査読有り

Y. Gando, A. Gando, T. Hachiya, S. Hayashida, K. Hosokawa, H. Ikeda, T. Mitsui, T. Nakada, S. Obara, H. Ozaki, J. Shirai, K. Ueshima, H. Watanabe, S. Abe, K. Hata, A. Hayashi, Y. Honda, S. Ieki, K. Inoue, K. Ishidoshiro, S. Ishikawa, Y. Kamei, K. Kamizawa, Y. Karino, N. Kawada, T. Kinoshita, M. Koga, S. Matsuda, H. Miyake, K. Nakamura, K. Nemoto, A. Ono, N. Ota, S. Otsuka, Y. Shibukawa, I. Shimizu, Y. Shirahata, K. Soma, A. Suzuki, A.A. Suzuki, T. Takai, A. Takeuchi, K. Tamae, Y. Teraoka, Y. Wada, D. Chernyak, A. Kozlov, S. Yoshida, S. Umehara, Y. Takemoto, K. Fushimi, S. Hirata, C. Grant, A. Li, J.G. Learned, J. Maricic, B.E. Berger, B.K. Fujikawa, S. Fraker, A. Herman, E. Krupczak, G.L. Pease, L.A. Winslow, Y. Efremenko, H.J. Karwowski, D.M. Markoff, W. Tornow, T. O'Donnell, S. Dell'Oro, J.A. Detwiler, S. Enomoto, M.P. Decowski

Journal of Instrumentation　16　(08)　P08023-P08023　2021年8月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1748-0221/16/08/p08023 　

eISSN：1748-0221
Low-energy astrophysics with KamLAND 査読有り

Nanami Kawada, Shuhei Obara, Koji Ishidoshiro, Seisho Abe, Sachihiro Asami, Azusa Gando, Yoshihito Gando, Tomomi Gima, Anna Goto, Takahiko Hachiya, Kazumi Hata, Shingo Hayashida, Keishi Hosokawa, Koichi Ichimura, Sei Ieki, Haruo Ikeda, Kunio Inoue, Yuto Kamei, Yasuhiro Kishimoto, Tatsuya Kinoshita, Masayuki Koga, Naoya Maemura, Tadao Mitsui, Haruhiko Miyake, Kengo Nakamura, Kosuke Nakamura, Rikuo Nakamura, Hideyoshi Ozaki, Taichi Sakai, Hiroto Sambonsugi, Itaru Shimizu, Junpei Shirai, Kensuke Shiraishi, Atsuto SUZUKI, Yuya Suzuki, Atsuto Takeuchi, Kyoko Tamae, Kota Ueshima, Yoshiki Wada, Hiroko Watanabe, Yuki Yoshida, Atsuko Ichikawa, Alexandre Kozlov, Dmitry CHERNYAK, Yasuhiro Takemoto, Sei Yoshida, Saori Umehara, Ken-Ichi Fushimi, Kazuhiro Nakamura, Masashi Yoshida, Bruce Edmond Berger, Brian Kurt Fujikawa, John Gregory Learned, Jelena Maricic, Spencer N. Axani, Lindley Anne Winslow, Zhenghao Fu, Jonathan Ouellet, Yuri Efremenko, Hugon J. Karwowski, Dian M. Markoff, Werner Tornow, Aobo Li, Jason A. Detwiler, Sanshiro Enomoto, Patric Decowski, Chistopher Grant, Thomas O'Donnell, Stefano Dell'Oro

2021年7月29日
出版者・発行元：None
DOI： 10.22323/1.395.1163 　
SNEWS 2.0: a next-generation supernova early warning system for multi-messenger astronomy 査読有り

S Al Kharusi, S Y BenZvi, J S Bobowski, W Bonivento, V Brdar, T Brunner, E Caden, M Clark, A Coleiro, M Colomer-Molla, J I Crespo-Anadón, A Depoian, D Dornic, V Fischer, D Franco, W Fulgione, A Gallo Rosso, M Geske, S Griswold, M Gromov, D Haggard, A Habig, O Halim, A Higuera, R Hill, S Horiuchi, K Ishidoshiro, C Kato, E Katsavounidis, D Khaitan, J P Kneller, A Kopec, V Kulikovskiy, M Lai, M Lamoureux, R F Lang, H L Li, M Lincetto, C Lunardini, J Migenda, D Milisavljevic, M E McCarthy, E O Connor, E O Sullivan, G Pagliaroli, D Patel, R Peres, B W Pointon, J Qin, N Raj, A Renshaw, A Roeth, J Rumleskie, K Scholberg, A Sheshukov, T Sonley, M Strait, V Takhistov, I Tamborra, J Tseng, C D Tunnell, J Vasel, C F Vigorito, B Viren, C J Virtue, J S Wang, L J Wen, L Winslow, F L H Wolfs, X J Xu, Y Xu

New Journal of Physics　23　(3)　031201-031201　2021年3月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1367-2630/abde33 　

eISSN：1367-2630
Search for Low-energy Electron Antineutrinos in KamLAND Associated with Gravitational Wave Events 査読有り

S. Abe, S. Asami, A. Gando, Y. Gando, T. Gima, A. Goto, T. Hachiya, K. Hata, S. Hayashida, K. Hosokawa, K. Ichimura, S. Ieki, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, Y. Kishimoto, T. Kinoshita, M. Koga, N. Maemura, T. Mitsui, H. Miyake, K. Nakamura, K. Nakamura, R. Nakamura, H. Ozaki, T. Sakai, H. Sambonsugi, I. Shimizu, J. Shirai, K. Shiraishi, A. Suzuki, Y. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, Y. Wada, H. Watanabe, Y. Yoshida, S. Obara, A. Kozlov, D. Chernyak, Y. Takemoto, S. Yoshida, S. Umehara, K. Fushimi, A. K. Ichikawa, K. Z. Nakamura, M. Yoshida, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, S. N. Axani, L. A. Winslow, Z. Fu, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, A. Li, J. A. Detwiler, S. Enomoto, M. P. Decowski, C. Grant, T. O’Donnell, S. Dell’Oro

The Astrophysical Journal　909　(2)　116-116　2021年3月1日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/abd5bc 　

ISSN：0004-637X

eISSN：1538-4357

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Abstract We present the results of a search for MeV-scale electron antineutrino events in KamLAND coincident with the 60 gravitational wave events/candidates reported by the LIGO/Virgo collaboration during their second and third observing runs. We find no significant coincident signals within a ±500 s timing window from each gravitational wave and present 90% C.L. upper limits on the electron antineutrino fluence between 108 and 1013 cm−2 for neutrino energies in the energy range of 1.8–111 MeV.
Supernova-scope for the direct search of Supernova axions 査読有り

Shao-Feng Ge, Koichi Hamaguchi, Koichi Ichimura, Koji Ishidoshiro, Yoshiki Kanazawa, Yasuhiro Kishimoto, Natsumi Nagata, Jiaming Zheng

Journal of Cosmology and Astroparticle Physics　2020　(11)　059-059　2020年11月27日
出版者・発行元：IOP Publishing
DOI： 10.1088/1475-7516/2020/11/059 　

eISSN：1475-7516
Detectability of collective neutrino oscillation signatures in the supernova explosion of a 8.8 M⊙ star 査読有り

Hirokazu Sasaki, Tomoya Takiwaki, Shio Kawagoe, Shunsaku Horiuchi, Koji Ishidoshiro

Physical Review D　101　(6)　2020年3月26日
出版者・発行元：American Physical Society (APS)
DOI： 10.1103/physrevd.101.063027 　

ISSN：2470-0010

eISSN：2470-0029
Pre-supernova neutrino emission from massive stars and their detection

Chinami Kato, Hiroki Nagakura, Shun Furusawa, Koh Takahashi, Hideyuki Umeda, Takashi Yoshida, Koji Ishidoshiro, Shoichi Yamada

Journal of Physics: Conference Series　1468　(1)　2020年3月20日

DOI： 10.1088/1742-6596/1468/1/012173 　

ISSN：1742-6588

eISSN：1742-6596

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Recent progress of neutrino detectors makes it possible to detect pre-SN neutrinos, which are emitted from the core of massive stars before supernova explosions. Pre-SN neutrino observations will become an alarm for supernovae. We hence calculate the number luminosity and energy spectra of pre-SN neutrinos from the 15 M o progenitor based on the state-of-the-art calculations of massive stars. We find that the number luminosity of ve 's is before core collapse and core bounce, respectively, whereas that of. We then estimate the number of neutrino events at neutrino detectors taking neutrino oscillations into the obtained luminosities and spectra. We find that an alarm is issued a few days before the explosion by detecting 's at liquid-scintilation type detectors if the progenitor is located at 200 pc. Finally, we perform a systematic study of pre-SN neutrino emission for 7 progenitor models with different initial masses. We find that the difference of the number luminosities is ∼ 1 order and the dependence of the initial mass have to be taken into the theoretical predictions of pre-SN neutrino observations.
Scintillation balloon for liquid scintillator base Neutrinoless double beta decay search experiments 査読有り

S.Obara, Y.Gando, K.Ishidoshiro

Journal of Physics: Conference Series　1468　012136-012136　2020年2月
出版者・発行元：None
DOI： 10.1088/1742-6596/1468/1/012136 　

ISSN：1742-6588

eISSN：1742-6596
Pulsational Pair-instability Supernovae. II. Neutrino Signals from Pulsations and Their Detection by Terrestrial Neutrino Detectors 査読有り

Shing-Chi Leung, Sergei Blinnikov, Koji Ishidoshiro, Alexandre Kozlov, Ken’ichi Nomoto

The Astrophysical Journal　889　(2)　75-75　2020年1月28日
出版者・発行元：American Astronomical Society
DOI： 10.3847/1538-4357/ab6211 　

eISSN：1538-4357
Scintillation balloon for neutrinoless double-beta decay search with liquid scintillator detectors 査読有り

Obara S, Gando Y, Ishidoshiro K

PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS　(7)　2019年7月

DOI： 10.1093/ptep/ptz064 　

ISSN：2050-3911
Precision Analysis of the Xe 136 Two-Neutrino ββ Spectrum in KamLAND-Zen and Its Impact on the Quenching of Nuclear Matrix Elements 査読有り

A. Gando, Y. Gando, T. Hachiya, M. Ha Minh, S. Hayashida, Y. Honda, K. Hosokawa, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, K. Kamizawa, T. Kinoshita, M. Koga, S. Matsuda, T. Mitsui, K. Nakamura, A. Ono, N. Ota, S. Otsuka, H. Ozaki, Y. Shibukawa, I. Shimizu, Y. Shirahata, J. Shirai, T. Sato, K. Soma, A. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, H. Watanabe, D. Chernyak, A. Kozlov, S. Obara, S. Yoshida, Y. Takemoto, S. Umehara, K. Fushimi, S. Hirata, B. E. Berger, B. K. Fujikawa, J. G. Learned, J. Maricic, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, T. O'Donnell, J. A. Detwiler, S. Enomoto, M. P. Decowski, J. Menéndez, R. Dvornický, F. Šimkovic

Physical Review Letters　122　(19)　2019年5月13日

DOI： 10.1103/PhysRevLett.122.192501 　

ISSN：0031-9007

eISSN：1079-7114

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© 2019 authors. Published by the American Physical Society. We present a precision analysis of the Xe136 two-neutrino ββ electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ββ rate allows us to measure the ratio of the leading and subleading 2νββ nuclear matrix elements (NMEs), ζ312ν=-0.26-0.25+0.31. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ζ312ν range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ζ312ν values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ββ decay, ζ312ν provides new insights toward reliable neutrinoless ββ NMEs.
Dark Matter Search with Superconducting Detector 査読有り

Proceedings of International Conference on Technology and Instrumentation in Particle Physics 2017　97-100　2018年8月
Kamland-zen

S. Abe, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, K. Hosokawa, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Kamei, N. Kawada, T. Kinoshita, M. Koga, T. Mitsui, H. Miyake, K. Nakamura, S. Obara, A. Ohno, N. Ohta, S. Ohtsuka, H. Ozaki, T. Sato, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, A. Takeuchi, K. Tamae, K. Ueshima, Y. Wada, H. Watanabe, A. Kozlov, D. Chernyak, Y. Takemoto, S. Umehara, S. Yoshida, K. Fushimi, S. Hirata, B. E. Berger, B. K. Fujikawa, L. A. Winslow, J. Ouellet, E. Krupczak, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, T. O’Donnell, J. A. Detwiler, S. Enomoto, M. P. Decowski

Neutrino 2018 - 28th International Conference on Neutrino Physics and Astrophysics, Conference Proceedings　2018年
A Search for Electron Antineutrinos Associated with Gravitational-wave Events GW150914 and GW151226 Using KamLAND (vol 829, L34, 2016) 査読有り

A. Gando, Y. Gando, T. Hachiya, A. Hayashi, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Karino, M. Koga, S. Matsuda, T. Mitsui, K. Nakamura, S. Obara, T. Oura, H. Ozaki, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, T. Takai, K. Tamae, Y. Teraoka, K. Ueshima, H. Watanabe, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, A. Piepke, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, J. G. Learned, J. Maricic, M. Sakai, L. A. Winslow, E. Krupczak, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

ASTROPHYSICAL JOURNAL LETTERS　851　(1)　2017年12月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.3847/2041-8213/aa9a32 　

ISSN：2041-8205

eISSN：2041-8213
Neutrino Emissions in All Flavors up to the Pre-bounce of Massive Stars and the Possibility of Their Detections 査読有り

Chinami Kato, Hiroki Nagakura, Shun Furusawa, Koh Takahashi, Hideyuki Umeda, Takashi Yoshida, Koji Ishidoshiro, Shoichi Yamada

ASTROPHYSICAL JOURNAL　848　(1)　48　2017年10月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.3847/1538-4357/aa8b72 　

ISSN：0004-637X

eISSN：1538-4357

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This paper is a sequel to our 2015 paper, Kato et al., which calculated the luminosities and spectra of electron-type anti-neutrinos ((v) over bar (e)) from the progenitors of core-collapse supernovae. Expecting that the capability to detect electron-type neutrinos (ne) will increase dramatically with the emergence of liquid-argon detectors such as DUNE, we broaden the scope in this study to include all flavors of neutrinos emitted from the pre-bounce phase. We pick up three progenitor models of electron capture supernovae (ECSNe) and iron-core collapse supernovae (FeCCSNe). We find that the number luminosities reach similar to 10(57) s(-1). and similar to 10(53) s(-1) at maximum for v(e) and (v) over bar (e), respectively. We also estimate the numbers of detection events at terrestrial neutrino detectors including DUNE, taking flavor oscillations into account and assuming the distance to the progenitors to be 200 pc. It is demonstrated that (v) over bar (e) from the ECSN progenitor will be undetected at almost all detectors, whereas we will be able to observe greater than or similar to 15,900 v(e) at DUNE for the inverted mass hierarchy. From the FeCCSN progenitors, the number of (v) over bar (e) events will be largest for JUNO, 200-900 v(e), depending on the mass hierarchy, whereas the number of ne events at DUNE is greater than or similar to 2100 for the inverted mass hierarchy. These results imply that the detection of (v) over bar (e) is useful to distinguish progenitors of FeCCSNe from those of ECSNe, while ne will provide us with detailed information on the collapse phase regardless of the type and mass of the progenitor.
Observations of presupernova neutrinos relating to the nal evolution of massive stars 査読有り

T. Yoshida, K. Takahashi, H. Umeda, K. Ishidoshiro

Journal of Physics: Conference Series　888　(1)　2017年9月20日
出版者・発行元：Institute of Physics Publishing
DOI： 10.1088/1742-6596/888/1/012259 　

ISSN：1742-6596 1742-6588

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We investigate neutrino events from presupernova stars at the distance of 200 pc detected by current and future neutrino observatories. The spectrum evolution of neutrinos emitted from presupernova stars of 12, 15, and 20 M after the O burning until the core collapse is evaluated. The expected events are several to more than ten for KamLAND and are hundreds for JUNO and Hyper-K. The time evolution of the events could reveal the evidence for the change of burning processes during the nal evolution of massive stars. We propose the detection of presupernova neutrinos by Gd-loaded Super-K and Hyper-K using the delayed γ-ray signals of Gd(n, γ) reaction. Gd-loaded Super-K and Hyper-K have a possibility for the detection of hundreds and thousands neutrino events, respectively. We also estimate the time for supernova alarms using presupernova neutrinos. KamLAND, JUNO, and other neutrino detectors could send supernova alarms using presupernova neutrinos several hours to one day before a supernova explosion. Multiple observations of presupernova neutrinos will raise the reliability of the supernova alarm.
Pre-SN neutrino emissions from ONe cores in the progenitors of CCSNe 査読有り

Kato Chinami, Yamada S, Nagakura H, Furusawa S, Takahashi K, Umeda H, Yoshida T, Ishidoshiro K

LIVES AND DEATH-THROES OF MASSIVE STARS　12　(S329)　411　2017年

DOI： 10.1017/S1743921317002502 　

ISSN：1743-9213
A SEARCH FOR ELECTRON ANTINEUTRINOS ASSOCIATED WITH GRAVITATIONAL-WAVE EVENTS GW150914 AND GW151226 USING KAMLAND 査読有り

A. Gando, Y. Gando, T. Hachiya, A. Hayashi, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Karino, M. Koga, S. Matsuda, T. Mitsui, K. Nakamura, S. Obara, T. Oura, H. Ozaki, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, T. Takai, K. Tamae, Y. Teraoka, K. Ueshima, H. Watanabe, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, A. Piepke, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, J. G. Learned, J. Maricic, M. Sakai, L. A. Winslow, E. Krupczak, J. Ouellet, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

ASTROPHYSICAL JOURNAL LETTERS　829　(2)　L34　2016年10月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.3847/2041-8205/829/2/L34 　

ISSN：2041-8205

eISSN：2041-8213

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We present a search, using KamLAND, a kiloton-scale anti-neutrino detector, for low-energy anti-neutrino events that were coincident with the gravitational-wave (GW) events GW150914 and GW151226, and the candidate event LVT151012. We find no inverse beta-decay neutrino events within +/-500 s of either GW signal. This non-detection is used to constrain the electron anti-neutrino fluence and the total integrated luminosity of the astrophysical sources.
Search for Majorana Neutrinos Near the Inverted Mass Hierarchy Region with KamLAND-Zen 査読有り

A. Gando, Y. Gando, T. Hachiya, A. Hayashi, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, Y. Karino, M. Koga, S. Matsuda, T. Mitsui, K. Nakamura, S. Obara, T. Oura, H. Ozaki, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, T. Takai, K. Tamae, Y. Teraoka, K. Ueshima, H. Watanabe, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

PHYSICAL REVIEW LETTERS　117　(8)　082503　2016年8月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevLett.117.082503 　

ISSN：0031-9007

eISSN：1079-7114

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We present an improved search for neutrinoless double-beta (0 nu beta beta) decay of Xe-136 in the KamLAND-Zen experiment. Owing to purification of the xenon-loaded liquid scintillator, we achieved a significant reduction of the Ag-110m contaminant identified in previous searches. Combining the results from the first and second phase, we obtain a lower limit for the 0 nu beta beta decay half-life of T-1/2(0 nu) > 1.07 x 10(26) yr at 90% C.L., an almost sixfold improvement over previous limits. Using commonly adopted nuclear matrix element calculations, the corresponding upper limits on the effective Majorana neutrino mass are in the range 61-165 meV. For the most optimistic nuclear matrix elements, this limit reaches the bottom of the quasidegenerate neutrino mass region.
Presupernova neutrino events relating to the final evolution of massive stars 査読有り

Takashi Yoshida, Koh Takahashi, Hideyuki Umeda, Koji Ishidoshiro

PHYSICAL REVIEW D　93　(12)　123012　2016年6月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevD.93.123012 　

ISSN：2470-0010

eISSN：2470-0029

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When a supernova explosion occurs in neighbors around hundreds pc, current and future neutrino detectors are expected to observe neutrinos from the presupernova star before the explosion. We show a possibility for obtaining the evidence for burning processes in the central region of presupernova stars though the observations of neutrino signals by current and future neutrino detectors such as KamLAND, JUNO, and Hyper-Kamiokande. We also investigate supernova alarms using neutrinos from presupernova stars in neighbors. If a supernova explodes at similar to 200 pc, future 20 kton size liquid scintillation detectors are expected to observe hundreds neutrino events. We also propose a possibility of the detection of neutrino events by Gd-loaded Hyper-Kamiokande using delayed gamma-ray signals. These detectors could observe detailed time variation of neutrino events. The neutrino emission rate increases by the core contraction in the final evolution stage. However, the O and Si shell burnings suppress the neutrino emission for a moment. The observed decrease in the neutrino event rate before hours to the explosion is possibly evidence for the shell burnings. The observations of detailed time evolution of presupernova neutrino events could reveal properties of burning processes in the central region of presupernova stars.
Search for double-beta decay of Xe-136 to excited states of Ba-136 with the KamLAND-Zen experiment 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, M. Otani, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

NUCLEAR PHYSICS A　946　171-181　2016年2月
出版者・発行元：ELSEVIER SCIENCE BV
DOI： 10.1016/j.nuclphysa.2015.11.011 　

ISSN：0375-9474

eISSN：1873-1554

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A search for double-beta decays of Xe-136 to excited states of Ba-136 has been performed with the first phase data set of the KamLAND-Zen experiment. The 0(1)(+), 2(1)(+) and 2(2)(+) transitions of 0 nu beta beta decay were evaluated in an exposure of 89.5 kg. yr of Xe-136, while the same transitions of 2 nu beta beta decay were evaluated in an exposure of 61.8 kg. yr. No excess over background was found for all decay modes. The lower half-life limits of the 2(1)(+) state transitions of 0 nu beta beta and 2 nu beta beta decay were improved to T-1/2(0 nu) (0(+) -> 2(1)(+)) > 2.6 x 10(25) yr and T-1/2(2 nu)) (0(+) -> 2(1)(+)) > 4.6 x 10(23) yr (90% C.L.), respectively. We report on the first experimental lower half-life limits for the transitions to the 0(1)(+) Oil-state of Xe-136 for 0 nu beta beta and 2 nu beta beta decay. They are T-1/2(0 nu) (0(+) -> 0(1)(+)) > 2.4 x 10(25) yr and T-1/2(2 nu)(0(+) -> 0(1)(+)) > 8.3 x 10(23) yr (90% C.L.). The transitions to the 22 states are also evaluated for the first time to be T-1/2(0 nu) (0(+) -> 2(2)(+)) > 2.6 x 10(25) yr and T-1/2(2 nu) (0(+) -> 2(2)(+)) > 9.0 x 10(23) yr (90% C.L.). These results are compared to recent theoretical predictions. (C) 2015 Elsevier B.V. All rights reserved.
Be-7 solar neutrino measurement with KamLAND 査読有り

A. Gando, Y. Gando, H. Hanakago, H. Ikeda, K. Inoue, K. Ishidoshiro, H. Ishikawa, Y. Kishimoto, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakajima, K. Nakamura, A. Obata, A. Oki, Y. Oki, M. Otani, I. Shimizu, J. Shirai, A. Suzuki, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, S. Yamada, Y. Yamauchi, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, C. Grant, G. Keefer, D. W. McKee, A. Piepke, T. I. Banks, T. Bloxham, S. J. Freedman, B. K. Fujikawa, K. Han, L. Hsu, K. Ichimura, H. Murayama, T. O'Donnell, H. M. Steiner, L. A. Winslow, D. Dwyer, C. Mauger, R. D. McKeown, C. Zhang, B. E. Berger, C. E. Lane, J. Maricic, T. Miletic, J. G. Learned, M. Sakai, G. A. Horton-Smith, A. Tang, K. E. Downum, K. Tolich, Y. Efremenko, Y. Kamyshkov, O. Perevozchikov, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, K. Heeger, M. P. Decowski

PHYSICAL REVIEW C　92　(5)　055808　2015年11月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevC.92.055808 　

ISSN：0556-2813

eISSN：1089-490X

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We report a measurement of the neutrino-electron elastic scattering rate of 862 keV Be-7 solar neutrinos based on a 165.4 kt d exposure of KamLAND. The observed rate is 582 +/- 94(kt d)(-1), which corresponds to an 862-keV Be-7 solar neutrino flux of (3.26 +/- 0.52) x 10(9) cm(-2) s(-1), assuming a pure electron-flavor flux. Comparing this flux with the standard solar model prediction and further assuming three-flavor mixing, a.e survival probability of 0.66 +/- 0.15 is determined from the KamLAND data. Utilizing a global three-flavor oscillation analysis, we obtain a total Be-7 solar neutrino flux of (5.82 +/- 1.02) x 10(9) cm(-2) s(-1), which is consistent with the standard solar model predictions.
Search for the proton decay mode p → ν ¯ K+ with KamLAND SEARCH for the PROTON DECAY MODE ⋯ K. ASAKURA et al

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, K. Nakamura, S. Obara, Y. Oki, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, Y. Yamauchi, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, C. Grant, A. Piepke, A. Piepke, T. I. Banks, B. E. Berger, B. E. Berger, S. J. Freedman, B. K. Fujikawa, B. K. Fujikawa, T. O'Donnell, T. O'Donnell, J. G. Learned, J. Maricic, M. Sakai, S. Dazeley, R. Svoboda, L. A. Winslow, Y. Efremenko, Y. Efremenko, H. J. Karwowski, H. J. Karwowski, H. J. Karwowski, H. J. Karwowski, D. M. Markoff, W. Tornow, W. Tornow, J. A. Detwiler, S. Enomoto, S. Enomoto, M. P. Decowski, M. P. Decowski

Physical Review D - Particles, Fields, Gravitation and Cosmology　92　(5)　2015年9月23日
出版者・発行元：None
DOI： 10.1103/PhysRevD.92.052006 　

ISSN：1550-2368 1550-7998

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© 2015 American Physical Society. We present a search for the proton decay mode p→ν¯K+ based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from p→ν¯K+ with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is 0.9±0.2 events. The nonbackground-subtracted limit on the partial proton lifetime is τ/B(p→ν¯K+)>5.4×1032years at 90% C.L.
Search for the proton decay mode p -> (v)over-barK(+) with KamLAND 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, Y. Oki, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, Y. Yamauchi, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, C. Grant, A. Piepke, T. I. Banks, B. E. Berger, S. J. Freedman, B. K. Fujikawa, T. O'Donnell, J. G. Learned, J. Maricic, M. Sakai, S. Dazeley, R. Svoboda, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

PHYSICAL REVIEW D　92　(5)　052006　2015年9月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevD.92.052006 　

ISSN：2470-0010

eISSN：2470-0029

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We present a search for the proton decay mode p ->(v) over barK(+) based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from p ->(v) over barK(+) with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is 0.9 +/- 0.2 events. The nonbackground-subtracted limit on the partial proton lifetime is tau/B (p ->(v) over barK(+)) > 5.4 x 10(32) years at 90% C. L.
PRE-SUPERNOVA NEUTRINO EMISSIONS FROM ONe. CORES IN THE PROGENITORS OF CORE-COLLAPSE SUPERNOVAE: ARE THEY DISTINGUISHABLE FROM THOSE OF Fe CORES? 査読有り

Chinami Kato, Milad Delfan Azari, Shoichi Yamada, Koh Takahashi, Hideyuki Umeda, Takashi Yoshida, Koji Ishidoshiro

ASTROPHYSICAL JOURNAL　808　(2)　168　2015年8月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0004-637X/808/2/168 　

ISSN：0004-637X

eISSN：1538-4357

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Aiming to distinguish two types of progenitors of core-collapse supernovae, i.e., one with a core composed mainly of oxygen and neon (abbreviated as ONe core) and the other with an iron core (or Fe core), we calculated the luminosities and spectra of neutrinos emitted from these cores prior to gravitational collapse, taking neutrino oscillation into account. We found that the total energies emitted as (nu) over bar (e) from the ONe core are less than or similar to 10(46) erg, which is much smaller than similar to 10(47) erg for Fe cores. The average energy, on the other hand, is twice as large for the ONe core as those for the Fe cores. The neutrinos produced by the plasmon decays in the ONe core are more numerous than those from the electron-positron annihilation in both cores, but they have much lower average energies less than or similar to 1 MeV. Although it is difficult to detect the pre-supernova neutrinos from the ONe core even if it is located within 200 pc from Earth, we expect similar to 9-43 and similar to 7-61 events for Fe cores at KamLAND and Super-Kamiokande, respectively, depending on the progenitor mass and neutrino-mass hierarchy. These numbers might be increased by an order of magnitude if we envisage next-generation detectors such as JUNO. We will hence be able to distinguish the two types of progenitors by the detection or nondetection of the pre-supernova neutrinos if they are close enough (less than or similar to 1 kpc).
Results from KamLAND-Zen 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, Y. Oki, M. Otani, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, Y. Yamauchi, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, T. I. Banks, S. J. Freedman, B. K. Fujikawa, T. O'donnell, L. A. Winslow, B. E. Berger, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

AIP Conference Proceedings　1666　(170003)　1-8　2015年7月15日
出版者・発行元：American Institute of Physics Inc.
DOI： 10.1063/1.4915593 　

ISSN：1551-7616 0094-243X

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KamLAND-Zen reports on a preliminary search for neutrinoless double-beta decay with 136Xe based on 114.8 live-days after the purification of the xenon loaded liquid scintillator. In this data, the problematic 110mAg background peak identified in previous searches is reduced by more than a factor of 10. By combining the KamLAND-Zen pre- and post-purification data, we obtain a preliminary lower limit on the 0νββ decay half-life of T1/20ν&gt 2.6ï¿½1025 yr at 90% C.L. The search sensitivity will be enhanced with additional low background data after the purification. Prospects for further improvements with future KamLAND-Zen upgrades are also presented.
STUDY OF ELECTRON ANTI-NEUTRINOS ASSOCIATED WITH GAMMA-RAY BURSTS USING KamLAND 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, Y. Oki, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, A. Piepke, T. I. Banks, B. E. Berger, B. K. Fujikawa, T. O'Donnell, J. G. Learned, J. Maricic, M. Sakai, L. A. Winslow, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

ASTROPHYSICAL JOURNAL　806　(1)　87　2015年6月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0004-637X/806/1/87 　

ISSN：0004-637X

eISSN：1538-4357

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We search for electron anti-neutrinos ((V) over bar (e)) from long- and short-duration gamma-ray bursts (GRBs) using data taken by the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) from 2002 August to 2013 June. No statistically significant excess over the background level is found. We place the tightest upper limits on (V) over bar (e) fluence from GRBs below 7 MeV and place first constraints on the relation between (V) over bar (e) luminosity and effective temperature.
23pDM-13 銀河系内超新星候補天体リストに基づく観測ネットワーク構築

大石奈緒子, 田中雅臣, 石徹白晃治, 小汐由介, 田越秀行, 神田展行

日本物理学会講演概要集　70　484-484　2015年
出版者・発行元：一般社団法人日本物理学会
DOI： 10.11316/jpsgaiyo.70.1.0_484 　

ISSN：2189-079X
23pDM-7 超新星前兆ニュートリノの放出率及びその観測可能性

加藤ちなみ, 山田章一, 高橋亘, 石徹白晃治

日本物理学会講演概要集　70　479-479　2015年
出版者・発行元：一般社団法人日本物理学会
DOI： 10.11316/jpsgaiyo.70.1.0_479 　

ISSN：2189-079X
Results from KamLAND-Zen 査読有り

K. Asakura, A. Gando, Y. Gando, T. Hachiya, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, T. Ishikawa, S. Ishio, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, S. Obara, Y. Oki, M. Otani, T. Oura, I. Shimizu, Y. Shirahata, J. Shirai, A. Suzuki, H. Tachibana, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, Y. Yamauchi, H. Yoshida, A. Kozlov, Y. Takemoto, S. Yoshida, K. Fushimi, T. I. Banks, S. J. Freedman, B. K. Fujikawa, T. O'Donnell, L. A. Winslow, B. E. Berger, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

XXVI INTERNATIONAL CONFERENCE ON NEUTRINO PHYSICS AND ASTROPHYSICS (NEUTRINO 2014)　1666　2015年
出版者・発行元：AMER INST PHYSICS
DOI： 10.1063/14915593 　

ISSN：0094-243X

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KamLAND-Zen reports on a preliminary search for neutrinoless double-beta decay with Xe-136 based on 114.8 live-days after the purification of the xenon loaded liquid scintillator. In this data, the problematic Ag-11 m background peak identified in previous searches is reduced by more than a factor of 10. By combining the KamLAND-Zen pre- and post-purification data, we obtain a preliminary lower limit on the 0 nu beta beta decay half-life of T-1/2(0 nu) > 2.6 x 10(25) yr at 90% C.L. The search sensitivity will be enhanced with additional low background data after the purification. Prospects for further improvements with future KamLAND-Zen upgrades are also presented.
Mission Design of LiteBIRD 査読有り

T. Matsumura, Y. Akiba, J. Borrill, Y. Chinone, M. Dobbs, H. Fuke, A. Ghribi, M. Hasegawa, K. Hattori, M. Hattori, M. Hazumi, W. Holzapfel, Y. Inoue, K. Ishidoshiro, H. Ishino, H. Ishitsuka, K. Karatsu, N. Katayama, I. Kawano, A. Kibayashi, Y. Kibe, K. Kimura, N. Kimura, K. Koga, M. Kozu, E. Komatsu, A. Lee, H. Matsuhara, S. Mima, K. Mitsuda, K. Mizukami, H. Morii, T. Morishima, S. Murayama, M. Nagai, R. Nagata, S. Nakamura, M. Naruse, K. Natsume, T. Nishibori, H. Nishino, A. Noda, T. Noguchi, H. Ogawa, S. Oguri, I. Ohta, C. Otani, P. Richards, S. Sakai, N. Sato, Y. Sato, Y. Sekimoto, A. Shimizu, K. Shinozaki, H. Sugita, T. Suzuki, A. Suzuki, O. Tajima, S. Takada, S. Takakura, Y. Takei, T. Tomaru, Y. Uzawa, T. Wada, H. Watanabe, M. Yoshida, N. Yamasaki, T. Yoshida, K. Yotsumoto

JOURNAL OF LOW TEMPERATURE PHYSICS　176　(5-6)　733-740　2014年9月
出版者・発行元：SPRINGER/PLENUM PUBLISHERS
DOI： 10.1007/s10909-013-0996-1 　

ISSN：0022-2291

eISSN：1573-7357

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LiteBIRD is a next-generation satellite mission to measure the polarization of the cosmic microwave background (CMB) radiation. On large angular scales the B-mode polarization of the CMB carries the imprint of primordial gravitational waves, and its precise measurement would provide a powerful probe of the epoch of inflation. The goal of LiteBIRD is to achieve a measurement of the characterizing tensor to scalar ratio to an uncertainty of . In order to achieve this goal we will employ a kilo-pixel superconducting detector array on a cryogenically cooled sub-Kelvin focal plane with an optical system at a temperature of 4 K. We are currently considering two detector array options; transition edge sensor (TES) bolometers and microwave kinetic inductance detectors. In this paper we give an overview of LiteBIRD and describe a TES-based polarimeter designed to achieve the target sensitivity of 2 K arcmin over the frequency range 50-320 GHz.
Progress and challenges in advanced ground-based gravitational-wave detectors 査読有り

M. Adier, F. Aguilar, T. Akutsu, M. A. Arain, M. Ando, L. Anghinolfi, P. Antonini, Y. Aso, B. W. Barr, L. Barsotti, M. G. Beker, A. S. Bell, L. Bellon, A. Bertolini, C. Blair, M. R. Blom, C. Bogan, C. Bond, F. S. Bortoli, D. Brown, B. C. Buchler, H. J. Bulten, G. Cagnoli, M. Canepa, L. Carbone, E. Cesarini, B. Champagnon, D. Chen, A. Chincarini, A. Chtanov, S. S. Y. Chua, G. Ciani, E. Coccia, A. Conte, M. Cortese, M. Daloisio, M. Damjanic, R. A. Day, D. De Ligny, J. Degallaix, M. Doets, V. Dolique, K. Dooley, S. Dwyer, M. Evans, M. Factourovich, V. Fafone, S. Farinon, D. Feldbaum, R. Flaminio, D. Forest, C. Frajuca, M. Frede, A. Freise, T. Fricke, D. Friedrich, P. Fritschel, V. V. Frolov, P. Fulda, M. Geitner, G. Gemme, J. Gleason, S. Gossler, N. Gordon, C. Graef, M. Granata, S. Gras, M. Gross, H. Grote, R. Gustafson, M. Hanke, M. Heintze, E. Hennes, S. Hild, S. H. Huttner, K. Ishidoshiro, K. Izumi, K. Kawabe, S. Kawamura, F. Kawazoe, M. Kasprzack, A. Khalaidovski, N. Kimura, S. Koike, T. Kume, A. Kumeta, K. Kuroda, P. Kwee, B. Lagrange, P. K. Lam, M. Landry, S. Leavey, M. Leonardi, T. Li, Z. Liu, M. Lorenzini, G. Losurdo, D. Lumaca, J. Macarthur, N. S. Magalhaes, E. Majorana, V. Malvezzi, V. Mangano, G. Mansell, J. Marque, R. Martin, D. Martynov, N. Mavalvala, D. E. McClelland, G. D. Meadors, T. Meier, A. Mermet, C. Michel, Y. Minenkov, C. M. Mow-Lowry, L. Mudadu, C. L. Mueller, G. Mueller, F. Mul, D. Nanda Kumar, I. Nardecchia, L. Naticchioni, M. Neri, Y. Niwa, M. Ohashi, K. Okada, P. Oppermann, L. Pinard, J. Poeld, M. Prato, G. A. Prodi, O. Puncken, P. Puppo, V. Quetschke, D. H. Reitze, P. Risson, A. Rocchi, N. Saito, Y. Saito, Y. Sakakibara, B. Sassolas, A. Schimmel, R. Schnabel, R. M. S. Schofield, E. Schreiber, V. Sequino, E. Serra, D. A. Shaddock, A. Shoda, D. H. Shoemaker, K. Shibata, D. Sigg, N. Smith-Lefebvre, K. Somiya, B. Sorazu, M. S. Stefszky, K. A. Strain, N. Straniero, T. Suzuki, R. Takahashi, D. B. Tanner, G. Tellez, T. Theeg, C. Tokoku, K. Tsubono, T. Uchiyama, S. Ueda, H. Vahlbruch, G. Vajente, C. Vorvick, J. F. J. van den Brand, A. Wade, R. Ward, P. Wessels, L. Williams, B. Willke, L. Winkelmann, K. Yamamoto, J. -P. Zendri

GENERAL RELATIVITY AND GRAVITATION　46　(8)　2014年8月
出版者・発行元：SPRINGER/PLENUM PUBLISHERS
DOI： 10.1007/s10714-014-1749-4 　

ISSN：0001-7701

eISSN：1572-9532

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The Amaldi 10 Parallel Session C3 on Advanced Gravitational Wave detectors gave an overview of the status and several specific challenges and solutions relevant to the instruments planned for a mid-decade start of observation. Invited overview talks for the Virgo, LIGO, and KAGRA instruments were complemented by more detailed discussions in presentations and posters of some instrument features and designs.
LiteBIRD: Mission overview and design tradeoffs 査読有り

T. Matsumura, Y. Akiba, J. Borrill, Y. Chinone, M. Dobbs, H. Fuke, M. Hasegawa, K. Hattori, M. Hattori, M. Hazumi, W. Holzapfel, Y. Hori, J. Inatani, M. Inoue, Y. Inoue, K. Ishidoshiro, H. Ishino, H. Ishitsuka, K. Karatsu, S. Kashima, N. Katayama, I. Kawano, A. Kibayashi, Y. Kibe, K. Kimura, N. Kimura, E. Komatsu, M. Kozu, K. Koga, A. Lee, H. Matsuhara, S. Mima, K. Mitsuda, K. Mizukami, H. Morii, T. Morishima, M. Nagai, R. Nagata, S. Nakamura, M. Naruse, T. Namikawa, K. Natsume, T. Nishibori, K. Nishijo, H. Nishino, A. Noda, T. Noguchi, H. Ogawa, S. Oguri, I. S. Ohta, N. Okada, C. Otani, P. Richards, S. Sakai, N. Sato, Y. Sato, Y. Segawa, Y. Sekimoto, K. Shinozaki, H. Sugita, A. Suzuki, T. Suzuki, O. Tajima, S. Takada, S. Takakura, Y. Takei, T. Tomaru, Y. Uzawa, T. Wada, H. Watanabe, Y. Yamada, H. Yamaguchi, N. Yamasaki, M. Yoshida, T. Yoshida, K. Yotsumoto

SPACE TELESCOPES AND INSTRUMENTATION 2014: OPTICAL, INFRARED, AND MILLIMETER WAVE　9143　2014年
出版者・発行元：SPIE-INT SOC OPTICAL ENGINEERING
DOI： 10.1117/12.2055794 　

ISSN：0277-786X

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We present the mission design of LiteBIRD, a next generation satellite for the study of B-mode polarization and inflation from cosmic microwave background radiation (CMB) detection. The science goal of LiteBIRD is to measure the CMB polarization with the sensitivity of delta r = 0.001, and this allows testing the major single-field slow-roll inflation models experimentally. The LiteBIRD instrumental design is purely driven to achieve this goal. At the earlier stage of the mission design, several key instrumental specifications, e.g. observing band, optical system, scan strategy, and orbit, need to be de fined in order to process the rest of the detailed design. We have gone through the feasibility studies for these items in order to understand the tradeoffs between the requirements from the science goal and the compatibilities with a satellite bus system. We describe the overview of LiteBIRD and discuss the tradeoffs among the choices of scientific instrumental specifications and strategies. The first round of feasibility studies will be completed by the end of year 2014 to be ready for the mission definition review and the target launch date is in early 2020s.
Search for a stochastic gravitational-wave background using a pair of torsion-bar antennas 査読有り

Ayaka Shoda, Masaki Ando, Koji Ishidoshiro, Kenshi Okada, Wataru Kokuyama, Yoichi Aso, Kimio Tsubono

PHYSICAL REVIEW D　89　(2)　027101　2014年1月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevD.89.027101 　

ISSN：1550-7998

eISSN：1550-2368

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We have set a new upper limit on the stochastic gravitational-wave background using two prototype torsion-bar antennas (TOBAs). A TOBA is a low-frequency gravitational-wave detector with bar-shaped test masses rotated by the tidal force of gravitational waves. As a result of simultaneous 7-hour observations with TOBAs in Tokyo and Kyoto in Japan, our upper limit with a confidence level of 95% is Omega(gw)h(0)(2) < 1.9 x 10(17) at 0.035-0.830 Hz, where h(0) is the Hubble constant in units of 100 km/s/Mpc and Omega(gw) is the gravitational-wave energy density per logarithmic frequency interval in units of the closure density. We successfully updated the upper limit and extended the explored frequency band.
CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND

A. Gando, Y. Gando, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, H. Ishikawa, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, Y. Oki, M. Otani, I. Shimizu, J. Shirai, F. Suekane, A. Suzuki, Y. Takemoto, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, S. Yamada, Y. Yamauchi, H. Yoshida, M. Cribier, M. Durero, V. Fischer, J. Gaffiot, N. Jonqueres, A. Kouchner, T. Lasserre, D. Leterme, A. Letourneau, D. Lhuillier, G. Mention, G. Rampal, L. Scola, Ch. Veyssiere, M. Vivier, P. Yala, B. E. Berger, A. Kozlov, T. Banks, D. Dwyer, B. K. Fujikawa, K. Han, Yu. G. Kolomensky, Y. Mei, T. O'Donnell, P. Decowski, D. M. Markoff, S. Yoshida, V. N. Kornoukhov, T. V, M. Gelis, G. V. Tikhomirov, J. G. Learned, J. Maricic, S. Matsuno, R. Milincic, H. J. Karwowski, Y. Efremenko, A. Detwiler, S. Enomoto

2013年12月4日

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The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-background liquid scintillator detector. The antineutrino generator will be produced by the Russian reprocessing plant PA Mayak as early as 2014, transported to Japan, and deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) as early as 2015. KamLAND's 13 m diameter target volume provides a suitable environment to measure the energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, sterile neutrino state. This will provide a comprehensive test of the electron dissaperance neutrino anomalies and could lead to the discovery of a 4th neutrino state for Delta_m^2 > 0.1 eV^2 and sin^2(2theta) > 0.05.
White paper: CeLAND - Investigation of the reactor antineutrino anomaly with an intense 144Ce-144Pr antineutrino source in KamLAND

A. Gando, Y. Gando, S. Hayashida, H. Ikeda, K. Inoue, K. Ishidoshiro, H. Ishikawa, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, Y. Oki, M. Otani, I. Shimizu, J. Shirai, F. Suekane, A. Suzuki, Y. Takemoto, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, S. Yamada, Y. Yamauchi, H. Yoshida, T. Banks, B. E. Berger, M. Cribier, P. Decowski, J. A. Detwiler, M. Durero, D. Dwyer, Y. Efremenko, S. Enomoto, V. Fischer, B. K. Fujikawa, J. Gaffiot, V. M. Gelis, H. J. Karwowski, Yu. G. Kolomensky, A. Kozlov, V. N. Kornoukhov, T. Lasserre, J. G. Learned, A. Letourneau, D. Lhuillier, J. Maricic, D. M. Markoff, S. Matsuno, G. Mention, R. Milincic, T. ODonnell, I. S. Saldikov, L. Scola, G. V. Tikhomirov, Ch. Veyssiere, M. Vivier, S. Yoshida

2013年9月26日

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We propose to test for short baseline neutrino oscillations, implied by the recent reevaluation of the reactor antineutrino flux and by anomalous results from the gallium solar neutrino detectors. The test will consist of producing a 75 kCi 144Ce - 144Pr antineutrino source to be deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND). KamLAND's 13m diameter target volume provides a suitable environment to measure energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, "sterile" state. Such a measurement will be free of any reactor-related uncertainties. After 1.5 years of data taking the Reactor Antineutrino Anomaly parameter space will be tested at > 95% C.L.
Reactor on-off antineutrino measurement with KamLAND 査読有り

A. Gando, Y. Gando, H. Hanakago, H. Ikeda, K. Inoue, K. Ishidoshiro, H. Ishikawa, M. Koga, R. Matsuda, S. Matsuda, T. Mitsui, D. Motoki, K. Nakamura, A. Obata, A. Oki, Y. Oki, M. Otani, I. Shimizu, J. Shirai, A. Suzuki, Y. Takemoto, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, S. Yamada, Y. Yamauchi, H. Yoshida, A. Kozlov, S. Yoshida, A. Piepke, T. I. Banks, B. K. Fujikawa, K. Han, T. O'Donnell, B. E. Berger, J. G. Learned, S. Matsuno, M. Sakai, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

Physical Review D - Particles, Fields, Gravitation and Cosmology　88　(3)　033001　2013年8月2日

DOI： 10.1103/PhysRevD.88.033001 　

ISSN：1550-7998 1550-2368

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The recent long-term shutdown of Japanese nuclear reactors has resulted in a significantly reduced reactor ν̄e flux at KamLAND. This running condition provides a unique opportunity to confirm and constrain backgrounds for the reactor ν̄e oscillation analysis. The data set also has improved sensitivity for other ν̄e signals, in particular ν̄e's produced in β-decays from U238 and Th232 within the Earth's interior, whose energy spectrum overlaps with that of reactor ν̄e's. Including constraints on θ13 from accelerator and short-baseline reactor neutrino experiments, a combined three-flavor analysis of solar and KamLAND data gives fit values for the oscillation parameters of tan2θ12=0.436-0.025+0.029, Δm212=7.53-0.18+0.18×10-5 eV2, and sin2θ13=0.023-0.002+0.002. Assuming a chondritic Th/U mass ratio, we obtain 116-27+28 ν̄e events from U238 and Th232, corresponding to a geo ν̄e flux of 3.4-0.8+0.8×106 cm-2 s-1 at the KamLAND location. We evaluate various bulk silicate Earth composition models using the observed geo ν̄e rate. © 2013 American Physical Society.
THE Q/U IMAGING EXPERIMENT INSTRUMENT 査読有り

C. Bischoff, A. Brizius, I. Buder, Y. Chinone, K. Cleary, R. N. Dumoulin, A. Kusaka, R. Monsalve, S. K. Naess, L. B. Newburgh, G. Nixon, R. Reeves, K. M. Smith, K. Vanderlinde, I. K. Wehus, M. Bogdan, R. Bustos, S. E. Church, R. Davis, C. Dickinson, H. K. Eriksen, T. Gaier, J. O. Gundersen, M. Hasegawa, M. Hazumi, C. Holler, K. M. Huffenberger, W. A. Imbriale, K. Ishidoshiro, M. E. Jones, P. Kangaslahti, D. J. Kapner, C. R. Lawrence, E. M. Leitch, M. Limon, J. J. McMahon, A. D. Miller, M. Nagai, H. Nguyen, T. J. Pearson, L. Piccirillo, S. J. E. Radford, A. C. S. Readhead, J. L. Richards, D. Samtleben, M. Seiffert, M. C. Shepherd, S. T. Staggs, O. Tajima, K. L. Thompson, R. Williamson, B. Winstein, E. J. Wollack, J. T. L. Zwart

ASTROPHYSICAL JOURNAL　768　(1)　9　2013年5月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0004-637X/768/1/9 　

ISSN：0004-637X

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The Q/U Imaging ExperimenT (QUIET) is designed to measure polarization in the cosmic microwave background, targeting the imprint of inflationary gravitational waves at large angular scales(similar to 1 degrees). Between 2008 October and 2010 December, two independent receiver arrays were deployed sequentially on a 1.4 m side-fed Dragonian telescope. The polarimeters that form the focal planes use a compact design based on high electron mobility transistors (HEMTs) that provides simultaneous measurements of the Stokes parameters Q, U, and I in a single module. The 17-element Q-band polarimeter array, with a central frequency of 43.1 GHz, has the best sensitivity (69 mu Ks(1/2)) and the lowest instrumental systematic errors ever achieved in this band, contributing to the tensor-to-scalar ratio at r < 0.1. The 84-element W-band polarimeter array has a sensitivity of 87 mu Ks(1/2) at a central frequency of 94.5 GHz. It has the lowest systematic errors to date, contributing at r < 0.01. The two arrays together cover multipoles in the range l similar to 25-975. These are the largest HEMT-based arrays deployed to date. This article describes the design, calibration, performance, and sources of systematic error of the instrument.
The QUIET Instrument 査読有り

QUIET Collaboration, C. Bischoff, A. Brizius, I. Buder, Y. Chinone, K. Cleary, R. N. Dumoulin, A. Kusaka, R. Monsalve, S. K. Naess, L. B. Newburgh, G. Nixon, R. Reeves, K. M. Smith, K. Vanderlinde, I. K. Wehus, M. Bogdan, R. Bustos, S. E. Church, R. Davis, C. Dickinson, H. K. Eriksen, T. Gaier, J. O. Gundersen, M. Hasegawa, M. Hazumi, C. Holler, K. M. Huffenberger, W. A. Imbriale, K. Ishidoshiro, M. E. Jones, P. Kangaslahti, D. J. Kapner, C. R. Lawrence, E. M. Leitch, M. Limon, J. J. McMahon, A. D. Miller, M. Nagai, H. Nguyen, T. J. Pearson, L. Piccirillo, S. J. E. Radford, A. C, S. Readhead, J. L. Richards, D. Samtleben, M. Seiffert, M. C. Shepherd, S. T. Staggs, O. Tajima, K. L. Thompson, R. Williamson, B. Winstein, E. J. Wollack, J. T. L. Zwart

The Astrophysical Journal, Volume 768, Number 1　2013年4月

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The Q/U Imaging ExperimenT (QUIET) is designed to measure polarization in the Cosmic Microwave Background, targeting the imprint of inflationary gravitational waves at large angular scales (~ 1 degree). Between 2008 October and 2010 December, two independent receiver arrays were deployed sequentially on a 1.4 m side-fed Dragonian telescope. The polarimeters which form the focal planes use a highly compact design based on High Electron Mobility Transistors (HEMTs) that provides simultaneous measurements of the Stokes parameters Q, U, and I in a single module. The 17-element Q-band polarimeter array, with a central frequency of 43.1 GHz, has the best sensitivity (69 uK sqrt(s)) and the lowest instrumental systematic errors ever achieved in this band, contributing to the tensor-to-scalar ratio at r < 0.1. The 84-element W-band polarimeter array has a sensitivity of 87 uK sqrt(s) at a central frequency of 94.5 GHz. It has the lowest systematic errors to date, contributing at r < 0.01. The two arrays together cover multipoles in the range l= 25-975. These are the largest HEMT-based arrays deployed to date. This article describes the design, calibration, performance of, and sources of systematic error for the instrument.
Limit on neutrinoless ββ decay of Xe136 from the first phase of KamLAND-Zen and comparison with the positive claim in Ge76 査読有り

A. Gando, Y. Gando, H. Hanakago, H. Ikeda, K. Inoue, K. Ishidoshiro, R. Kato, M. Koga, S. Matsuda, T. Mitsui, D. Motoki, T. Nakada, K. Nakamura, A. Obata, A. Oki, Y. Ono, M. Otani, I. Shimizu, J. Shirai, A. Suzuki, Y. Takemoto, K. Tamae, K. Ueshima, H. Watanabe, B. D. Xu, S. Yamada, H. Yoshida, A. Kozlov, S. Yoshida, T. I. Banks, S. J. Freedman, B. K. Fujikawa, K. Han, T. O'Donnell, B. E. Berger, Y. Efremenko, H. J. Karwowski, D. M. Markoff, W. Tornow, J. A. Detwiler, S. Enomoto, M. P. Decowski

Physical Review Letters　110　(6)　062502　2013年2月7日

DOI： 10.1103/PhysRevLett.110.062502 　

ISSN：0031-9007 1079-7114

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We present results from the first phase of the KamLAND-Zen double-beta decay experiment, corresponding to an exposure of 89.5 kg yr of Xe136. We obtain a lower limit for the neutrinoless double-beta decay half-life of T1/20ν&gt 1.9×1025 yr at 90% C.L. The combined results from KamLAND-Zen and EXO-200 give T1/20ν&gt 3.4×1025 yr at 90% C.L., which corresponds to a Majorana neutrino mass limit of mββ &lt (120-250) meV based on a representative range of available matrix element calculations. Using those calculations, this result excludes the Majorana neutrino mass range expected from the neutrinoless double-beta decay detection claim in Ge76, reported by a part of the Heidelberg-Moscow Collaboration, at more than 97.5% C.L. © 2013 American Physical Society.
SECOND SEASON QUIET OBSERVATIONS: MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRUM AT 95 GHz 査読有り

D. Araujo, C. Bischoff, A. Brizius, I. Buder, Y. Chinone, K. Cleary, R. N. Dumoulin, A. Kusaka, R. Monsalve, S. Kaess, L. B. Newburgh, R. Reeves, I. K. Wehus, J. T. L. Zwart, L. Bronfman, R. Bustos, S. E. Church, C. Dickinson, H. K. Eriksen, T. Gaier, J. O. Gundersen, M. Hasegawa, M. Hazumi, K. M. Huffenberger, K. Ishidoshiro, M. E. Jones, P. Kangaslahti, D. J. Kapner, D. Kubik, C. R. Lawrence, M. Limon, J. J. McMahon, A. D. Miller, M. Nagai, H. Nguyen, G. Nixon, T. J. Pearson, L. Piccirillo, S. J. E. Radford, A. C. S. Readhead, J. L. Richards, D. Samtleben, M. Seiffert, M. C. Shepherd, K. M. Smith, S. T. Staggs, O. Tajima, K. L. Thompson, K. Vanderlinde, R. Williamson

ASTROPHYSICAL JOURNAL　760　(2)　145　2012年12月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0004-637X/760/2/145 　

ISSN：0004-637X

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The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95 GHz. The 43 GHz results have been published in a previous paper, and here we report the measurement of CMB polarization power spectra using the 95 GHz data. This data set comprises 5337 hr of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 mu K root s. Four low-foreground fields were observed, covering a total of similar to 1000 deg(2) with an effective angular resolution of 12.'8, allowing for constraints on primordial gravitational waves and high signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C-l (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB, and BB power spectra between l = 25 and 975 and find that the EE spectrum is consistent with Lambda CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1(-0.8)(+0.9) (r < 2.8 at 95% C. L.) as derived by the ML pipeline, and r = 1.2(-0.8)(+0.9) (r < 2.7 at 95% C. L.) as derived by the PCL pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.
Readout System With On-Board Demodulation for CMB Polarization Experiments Using Coherent Polarimeter Arrays 査読有り

Koji Ishidoshiro, Makoto Nagai, Takeo Higuchi, Masaya Hasegawa, Masashi Hazumi, Masahiro Ikeno, Osamu Tajima, Manobu Tanaka, Tomohisa Uchida

IEEE TRANSACTIONS ON NUCLEAR SCIENCE　59　(3)　647-655　2012年6月
出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI： 10.1109/TNS.2012.2195029 　

ISSN：0018-9499

eISSN：1558-1578

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B-modes are special patterns in cosmic microwave background (CMB) polarization. Degree-scale B-modes are smoking-gun signatures of primordial gravitational waves. The generic strategy of CMB polarization experiments is to employ a large number of polarimeters for improving the statistics. The Q/U Imaging ExperimenT-II (QUIET-II) has been proposed to detect B-modes by using the world's largest coherent polarimeter array (2,000 channels). A unique detection technique using QUIET's polarimeters, which comprises a modulation/demodulation scheme, enables us to directly extract polarization signals. The extracted signals are free from unpolarized components and intrinsic noise. We developed a data readout system for the QUIET-II experiment. We employed a "master" clock strategy, on-board demodulation functions, and end-to-end Ethernet connections for logical simplicity and high-density compact electronics for physical compactness. A clock module acts as a single master and guarantees phase matching between the modulation by the polarimeters and the on-board demodulation by ADC modules. Each ADC module has 64 ADC chips in the VME-6U single slot size. Both modules have hardware processors for Ethernet TCP/UDP. All these modules and control computers are connected via end-to-end Ethernet. Physical compactness and logical simplicity enable us to easily handle a large number of polarimeters, while maintaining quality of the B-mode experiments. The developed electronics (the clock modules and the ADC modules) fulfill these requirements. Tests with a setup similar to that of the real experiment proved that the system works appropriately. The performance of all system components is validated to be suitable for B-mode measurements.
Ethernet-Based DAQ System for QUIET-II Detectors

M. Nagai, K. Ishidoshiro, T. Higuchi, M. Ikeno, M. Hasegawa, M. Hazumi, O. Tajima, M. Tanaka, T. Uchida

JOURNAL OF LOW TEMPERATURE PHYSICS　167　(5-6)　689-694　2012年6月
出版者・発行元：SPRINGER/PLENUM PUBLISHERS
DOI： 10.1007/s10909-012-0561-3 　

ISSN：0022-2291

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The B-modes in cosmic microwave background polarization are a smoking gun for the inflationary universe. For the detection of the B-modes, having a large detector array is a generic approach since the B-modes is so faint pattern (T (b)a parts per thousand(2)0.1 mu K). The Q/U Imaging ExperimenT Phase-II (QUIET-II) is proposed to search the B-modes, using an array with 500 HEMT-based polarimeters. Each polarimeter element has 4-outputs, therefore we have to manage 2000 channels in total. We developed a scalable DAQ system based on TCP/Ethernet for QUIET-II. The DAQ system is composed of the polarimeters, ADC boards, a Master Clock and a control computer (PC). The analog signals from the polarimeters are digitized on the ADC boards. On-board demodulation, which synchronizes the phase flip modulations on the polarimeter, extracts the polarized components in the digitized signal. The Master Clock distributes all necessary clocks to the ADC boards as well as the polarimeters. This scheme guarantees the synchronization of the modulations and demodulations. We employed Ethernet-based communication scheme between the data collection program (Collector) on the PC and the ADC boards as well as the Master Clock. Such an Ethernet-based communication scheme allows us to construct a simple structure of the upper level software, which results in the high scalability to increase the number of channels. All basic functions and requirements are confirmed by the laboratory tests; demonstration with test signals as well as the signals from the polarimeters, measurements of the data transfer rate, and the synchronous operation with two ADC boards. Therefore, the DAQ system is confirmed to be suitable for QUIET-II.
Laboratory Calibration System for CMB Polarization Detectors

M. Hasegawa, O. Tajima, Y. Chinone, M. Hazumi, K. Ishidoshiro, M. Nagai

JOURNAL OF LOW TEMPERATURE PHYSICS　167　(5-6)　892-897　2012年6月
出版者・発行元：SPRINGER/PLENUM PUBLISHERS
DOI： 10.1007/s10909-012-0508-8 　

ISSN：0022-2291

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We present a novel system to calibrate millimeter-wave polarimeters for CMB polarization measurements. This technique is an extension of the conventional metal mirror rotation approach, however it employs cryogenically-cooled blackbody absorbers. The primary advantage of this system is that it can generate a slightly polarized signal (similar to 100 mK) in the laboratory; this is at a similar level to that measured by ground-based CMB polarization experiments observing a similar to 10 K sky. It is important to reproduce the observing condition in the laboratory for reliable characterization of polarimeters before deployment. In this paper, we present the design and principle of the system, and demonstrate its use with a coherent-type polarimeter used for QUIET. This technique can also be applied to incoherent-type polarimeters and it is very promising for the next-generation CMB polarization experiments.
Note: Innovative demodulation scheme for coherent detectors in cosmic microwave background experiments 査読有り

K. Ishidoshiro, Y. Chinone, M. Hasegawa, M. Hazumi, M. Nagai, O. Tajima

REVIEW OF SCIENTIFIC INSTRUMENTS　83　(5)　056104　2012年5月
出版者・発行元：AMER INST PHYSICS
DOI： 10.1063/1.4719922 　

ISSN：0034-6748

eISSN：1089-7623

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We propose an innovative demodulation scheme for coherent detectors used in cosmic microwave background polarization experiments. Removal of non-white noise, e. g., narrow-band noise, in detectors is one of the key requirements for the experiments. A combination of modulation and demodulation is used to extract polarization signals as well as to suppress such noise. Traditional demodulation, which is based on the two-point numerical differentiation, works as a first-order high pass filter for the noise. The proposed demodulation is based on the three-point numerical differentiation. It works as a second-order high pass filter. By using a real detector, we confirmed significant improvements of suppression power for the narrow-band noise. We also found improvement of the noise floor. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4719922]
Laboratory characterization of CMB polarimeters using novel calibration system with cryogenically cooled loads

Makoto Nagai, Koji Ishidoshiro, Masaya Hasegawa, Masashi Hazumi, Osamu Tajima

MILLIMETER, SUBMILLIMETER, AND FAR-INFRARED DETECTORS AND INSTRUMENTATION FOR ASTRONOMY VI　8452　2012年
出版者・発行元：SPIE-INT SOC OPTICAL ENGINEERING
DOI： 10.1117/12.925626 　

ISSN：0277-786X

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Polarimeters used in cosmic microwave background (CMB) experiments must be well calibrated to measure faint CMB polarization patterns with low systematic errors. Polarimeter characteristics generally vary with the incident load temperature (T-load). Therefore, re-producing the observing conditions in the laboratory is an important concern. For polarimeters, we developed a characterization system with cryogenically cooled loads. The loads generate unpolarized radiation (15 K and 30 K), comparable to the typical sky temperature of the best sites on the ground, e.g., the Atacama Desert in Chile (T-load similar to 15 K). The radiation from the loads is reflected by a metal mirror in the cryostat, yielding partially polarized radiation (600 mK), entering a feed horn on the polarimeter. Rotation of the mirror alters the incident angle of the polarization and causes periodic switching of the load temperature for Y-factor measurements. We demonstrated the validity of the system using a polarimeter developed for an upgrade of QUIET (QUIET-II), which can obtain the Stokes parameters I, Q, and Usimultaneously. The system characterized all the necessary properties, e. g., the responses for I, Q, and U, and their crosstalk. In addition, a wide range of polarimeter bias conditions was surveyed. The principle of the characterization system is not limited to a particular frequency or detection scheme. Thus, various types of state-of-the-art detectors can be calibrated by using this system.
LiteBIRD: A small satellite for the studies of B-mode polarization and inflation from cosmic background radiation detection 査読有り

M. Hazumi, J. Borrill, Y. Chinone, M. A. Dobbs, H. Fuke, A. Ghribi, M. Hasegawa, K. Hattori, M. Hattori, W. L. Holzapfel, Y. Inoue, K. Ishidoshiro, H. Ishino, K. Karatsu, N. Katayama, I. Kawano, A. Kibayashi, Y. Kibe, N. Kimura, K. Koga, E. Komatsu, A. T. Lee, H. Matsuhara, T. Matsumura, S. Mima, K. Mitsuda, H. Morii, S. Murayama, M. Nagai, R. Nagata, S. Nakamura, K. Natsume, H. Nishino, A. Noda, T. Noguchi, I. Ohta, C. Otani, P. L. Richards, S. Sakai, N. Sato, Y. Sato, Y. Sekimoto, A. Shimizu, K. Shinozaki, H. Sugita, A. Suzuki, T. Suzuki, O. Tajima, S. Takada, Y. Takagi, Y. Takei, T. Tomaru, Y. Uzawa, H. Watanabe, N. Yamasaki, M. Yoshida, T. Yoshida, K. Yotsumoto

SPACE TELESCOPES AND INSTRUMENTATION 2012: OPTICAL, INFRARED, AND MILLIMETER WAVE　8442　2012年
出版者・発行元：SPIE-INT SOC OPTICAL ENGINEERING
DOI： 10.1117/12.926743 　

ISSN：0277-786X

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LiteBIRD [Lite (Light) satellite for the studies of B-mode polarization and Inflation from cosmic background Radiation Detection] is a small satellite to map the polarization of the cosmic microwave background (CMB) radiation over the full sky at large angular scales with unprecedented precision. Cosmological inflation, which is the leading hypothesis to resolve the problems in the Big Bang theory, predicts that primordial gravitational waves were created during the inflationary era. Measurements of polarization of the CMB radiation are known as the best probe to detect the primordial gravitational waves. The LiteBIRD working group is authorized by the Japanese Steering Committee for Space Science (SCSS) and is supported by JAXA. It has more than 50 members from Japan, USA and Canada. The scientific objective of LiteBIRD is to test all the representative inflation models that satisfy single-field slow-roll conditions and lie in the large-field regime. To this end, the requirement on the precision of the tensor-to-scalar ratio, r, at LiteBIRD is equal to or less than 0.001. Our baseline design adopts an array of multi-chroic superconducting polarimeters that are read out with high multiplexing factors in the frequency domain for a compact focal plane. The required sensitivity of 1.8 mu Karcmin is achieved with 2000 TES bolometers at 100mK. The cryogenic system is based on the Stirling/JT technology developed for SPICA, and the continuous ADR system shares the design with future X-ray satellites.
Search for a Stochastic Gravitational-wave Background with Torsion-bar Antennas 査読有り

Ayaka Shoda, Masaki Ando, Kenshi Okada, Koji Ishidoshiro, Wataru Kokuyama, Yoichi Aso, Kimio Tsubono

9TH EDOARDO AMALDI CONFERENCE ON GRAVITATIONAL WAVES (AMALDI 9) AND THE 2011 NUMERICAL RELATIVITY - DATA ANALYSIS MEETING (NRDA 2011)　363　2012年
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/1742-6596/363/1/012017 　

ISSN：1742-6588

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We performed a simultaneous observational run with prototypes of Torsion-bar Antenna (TOBA) and searched for a stochastic gravitational waves (GW) background. TOBA is a new type of GW detector which measures differential rotation of two test-mass bars caused by tidal force from GWs. It fundamentally has a good sensitivity at lower frequencies, such as 0.1 - 1.0 Hz. The prototype has a 20-cm test mass bar which is levitated by the pinning effect of a superconductor. The data was taken from 1:00 am to 10:00 am on March 11th 2011, at Tokyo and Kyoto in Japan. As a result, we did not detect a stochastic GW background with false alarm rate of 5 %, and set an upper limit on a stochastic GW background. Our 95 % confidence upper limit is Omega(gw)h(0)(2), < 1.2 x 10(19) at 0.06 - 0.9 Hz, where Omega(gw) is the GW energy density per logarithmic frequency interval in units of the critical density and h(0) is the Hubble constant per 100 km/sec/Mpc. We had established the simultaneous observation and the analysis pipeline with two TOBAs, and set an upper limit at a wider frequency band.
Calibration system with cryogenically-cooled loads for cosmic microwave background polarization detectors 査読有り

M. Hasegawa, O. Tajima, Y. Chinone, M. Hazumi, K. Ishidoshiro, M. Nagai

REVIEW OF SCIENTIFIC INSTRUMENTS　82　(5)　054501　2011年5月
出版者・発行元：AMER INST PHYSICS
DOI： 10.1063/1.3590931 　

ISSN：0034-6748

eISSN：1089-7623

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We present a novel system to calibrate millimeter-wave polarimeters for cosmic microwave background (CMB) polarization measurements. This technique is an extension of the conventional metal mirror rotation approach, however, it employs cryogenically-cooled blackbody absorbers. The primary advantage of this system is that it can generate a slightly polarized signal (similar to 100 mK) in the laboratory; this is at a similar level to that measured by ground-based CMB polarization experiments observing a similar to 10 K sky. It is important to reproduce the observing condition in the laboratory for reliable characterization of polarimeters before deployment. In this paper, we present the design and principle of the system and demonstrate its use with a coherent-type polarimeter used for an actual CMB polarization experiment. This technique can also be applied to incoherent-type polarimeters and it is very promising for the next-generation CMB polarization experiments. (C) 2011 American Institute of Physics. [doi:10.1063/1.3590931]
The Japanese space gravitational wave antenna: DECIGO 査読有り

Seiji Kawamura, Masaki Ando, Naoki Seto, Shuichi Sato, Takashi Nakamura, Kimio Tsubono, Nobuyuki Kanda, Takahiro Tanaka, Jun'ichi Yokoyama, Ikkoh Funaki, Kenji Numata, Kunihito Ioka, Takeshi Takashima, Kazuhiro Agatsuma, Tomotada Akutsu, Koh-suke Aoyanagi, Koji Arai, Akito Araya, Hideki Asada, Yoichi Aso, Dan Chen, Takeshi Chiba, Toshikazu Ebisuzaki, Yumiko Ejiri, Motohiro Enoki, Yoshiharu Eriguchi, Masa-Katsu Fujimoto, Ryuichi Fujita, Mitsuhiro Fukushima, Toshifumi Futamase, Tomohiro Harada, Tatsuaki Hashimoto, Kazuhiro Hayama, Wataru Hikida, Yoshiaki Himemoto, Hisashi Hirabayashi, Takashi Hiramatsu, Feng-Lei Hong, Hideyuki Horisawa, Mizuhiko Hosokawa, Kiyotomo Ichiki, Takeshi Ikegami, Kaiki T. Inoue, Koji Ishidoshiro, Hideki Ishihara, Takehiko Ishikawa, Hideharu Ishizaki, Hiroyuki Ito, Yousuke Itoh, Kiwamu Izumi, Isao Kawano, Nobuki Kawashima, Fumiko Kawazoe, Naoko Kishimoto, Kenta Kiuchi, Shiho Kobayashi, Kazunori Kohri, Hiroyuki Koizumi, Yasufumi Kojima, Keiko Kokeyama, Wataru Kokuyama, Kei Kotake, Yoshihide Kozai, Hiroo Kunimori, Hitoshi Kuninaka, Kazuaki Kuroda, Sachiko Kuroyanagi, Kei-ichi Maeda, Hideo Matsuhara, Nobuyuki Matsumoto, Yuta Michimura, Osamu Miyakawa, Umpei Miyamoto, Shinji Miyoki, Mutsuko Y. Morimoto, Toshiyuki Morisawa, Shigenori Moriwaki, Shinji Mukohyama, Mitsuru Musha, Shigeo Nagano, Isao Naito, Kouji Nakamura, Hiroyuki Nakano, Kenichi Nakao, Shinichi Nakasuka, Yoshinori Nakayama, Kazuhiro Nakazawa, Erina Nishida, Kazutaka Nishiyama, Atsushi Nishizawa, Yoshito Niwa, Taiga Noumi, Yoshiyuki Obuchi, Masatake Ohashi, Naoko Ohishi, Masashi Ohkawa, Kenshi Okada, Norio Okada, Kenichi Oohara, Norichika Sago, Motoyuki Saijo, Ryo Saito, Masaaki Sakagami, Shin-ichiro Sakai, Shihori Sakata, Misao Sasaki, Takashi Sato, Masaru Shibata, Hisaaki Shinkai, Ayaka Shoda, Kentaro Somiya, Hajime Sotani, Naoshi Sugiyama, Yudai Suwa, Rieko Suzuki, Hideyuki Tagoshi, Fuminobu Takahashi, Kakeru Takahashi, Keitaro Takahashi, Ryutaro Takahashi, Ryuichi Takahashi, Tadayuki Takahashi, Hirotaka Takahashi, Takamori Akiteru, Tadashi Takano, Nobuyuki Tanaka, Keisuke Taniguchi, Atsushi Taruya, Hiroyuki Tashiro, Yasuo Torii, Morio Toyoshima, Shinji Tsujikawa, Yoshiki Tsunesada, Akitoshi Ueda, Ken-ichi Ueda, Masayoshi Utashima, Yaka Wakabayashi, Kent Yagi, Hiroshi Yamakawa, Kazuhiro Yamamoto, Toshitaka Yamazaki, Chul-Moon Yoo, Shijun Yoshida, Taizoh Yoshino, Ke-Xun Sun

CLASSICAL AND QUANTUM GRAVITY　28　(9)　094011　2011年5月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0264-9381/28/9/094011 　

ISSN：0264-9381

eISSN：1361-6382

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The objectives of the DECi-hertz Interferometer Gravitational Wave Observatory (DECIGO) are to open a new window of observation for gravitational wave astronomy and to obtain insight into significant areas of science, such as verifying and characterizing inflation, determining the thermal history of the universe, characterizing dark energy, describing the formation mechanism of supermassive black holes in the center of galaxies, testing alternative theories of gravity, seeking black hole dark matter, understanding the physics of neutron stars and searching for planets around double neutron stars. DECIGO consists of four clusters of spacecraft in heliocentric orbits; each cluster employs three drag-free spacecraft, 1000 km apart from each other, whose relative displacements are measured by three pairs of differential Fabry-Perot Michelson interferometers. Two milestone missions, DECIGO pathfinder and Pre-DECIGO, will be launched to demonstrate required technologies and possibly to detect gravitational waves.
Upper Limit on Gravitational Wave Backgrounds at 0.2 Hz with a Torsion-Bar Antenna 査読有り

Koji Ishidoshiro, Masaki Ando, Akiteru Takamori, Hirotaka Takahashi, Kenshi Okada, Nobuyuki Matsumoto, Wataru Kokuyama, Nobuyuki Kanda, Yoichi Aso, Kimio Tsubono

PHYSICAL REVIEW LETTERS　106　(16)　161101　2011年4月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevLett.106.161101 　

ISSN：0031-9007

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We present the first upper limit on gravitational wave (GW) backgrounds at an unexplored frequency of 0.2 Hz using a torsion-bar antenna (TOBA). A TOBA was proposed to search for low-frequency GWs. We have developed a small-scaled TOBA and successfully found Omega(gw)(f) < 4.3 x 10(17) at 0.2 Hz as demonstration of the TOBA's capabilities, where Omega(gw)(f) is the GW energy density per logarithmic frequency interval in units of the closure density. Our result is the first nonintegrated limit to bridge the gap between the LIGO band (around 100 Hz) and the Cassini band (10(-6)-10(-4) Hz).
Readout system with on-board demodulation for CMB polarization experiments using coherent polarimeter array 査読有り

Koji Ishidoshiro, Makoto Nagai, Takeo Higuchi, Masaya Hasegawa, Masashi Hazumi, Masahiro Ikeno, Osamu Tajima, Manobu Tanaka, Tomohisa Uchida

2011 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (NSS/MIC)　1244-1251　2011年
出版者・発行元：IEEE
ISSN：1082-3654

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Special pattern in cosmic microwave background (CMB) polarization, B-modes, is a smoking-gun signature of primordial gravitational waves. Q/U Imaging ExperimenT-II (QUIET-II) is being proposed to detect the B-modes using the world's largest coherent polarimeter array (2,000 channels). Having a large number of polarimeters is the generic strategy of the CMB polarization experiments to improve the statistics. Unique detection technique using QUIET's polarimeters, modulation/demodulation scheme, enables us to directly extract polarization signal. The extracted signal is free from non-polarized components and intrinsic 1/f noise. We developed a data readout system including on-board demodulation function for the QUIET-II experiment. We employ a ''master'' clock strategy. This strategy guarantees phase matching between the modulation on the polarimeters and the demodulation on ADC modules. The single master organizes to generate all carrier clocks and distribute them to each module. The developed electronics, clock modules and the ADC modules, fulfill requirements. Tests with similar setup to the real observation proved that the system works properly. Their performances are confirmed to be suitable for the B-mode measurements.
Gravitational-wave detector realized by a superconductor 査読有り

K. Ishidoshiro, M. Ando, A. Takamori, K. Okada, K. Tsubono

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS　470　(20)　1841-1844　2010年11月
出版者・発行元：ELSEVIER SCIENCE BV
DOI： 10.1016/j.physc.2010.05.219 　

ISSN：0921-4534

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In this article, we present a new gravitational-wave detector based on superconducting magnetic levitation and results of its prototype test. Our detector is composed of the suspended test mass that is rotated by gravitational waves. Gravitational wave signals are readout by monitoring its angular motion. Superconducting magnetic levitation is used for the suspension of the test mass, since it has many advantages, such as zero mechanical loss and resonant frequency around its suspension axis in an ideal situation. For the study of actual performance of such gravitational-wave detector, a prototype detector has been developed. Using the prototype detector, the actual loss factor and resonant frequency are measured as 1.2 x 10(-8) Nms/rad and 5 mHz respectively. A detector noise is also evaluated. The current noise level is determined by the magnetic coupling with external magnetic field and mechanical coupling between translation and angular motion. The prototype detector has already one of the lowest noise levels for gravitational waves at 0.1 Hz among current gravitational-wave detectors. We have succeeded at the demonstration of the advantages of our torsion gravitational-wave detector. (C) 2010 Elsevier B.V. All rights reserved.
Torsion-Bar Antenna for Low-Frequency Gravitational-Wave Observations 査読有り

Masaki Ando, Koji Ishidoshiro, Kazuhiro Yamamoto, Kent Yagi, Wataru Kokuyama, Kimio Tsubono, Akiteru Takamori

PHYSICAL REVIEW LETTERS　105　(16)　161101　2010年10月
出版者・発行元：AMER PHYSICAL SOC
DOI： 10.1103/PhysRevLett.105.161101 　

ISSN：0031-9007

eISSN：1079-7114

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We propose a novel type of gravitational-wave antenna, formed by two bar-shaped test masses and laser-interferometric sensors to monitor their differential angular fluctuations. This antenna has a fundamental sensitivity to low-frequency signals below 1 Hz, even with a ground-based configuration. In addition, it is possible to expand the observation band to a lower limit determined by the observation time, by using modulation and up-conversion of gravitational-wave signals by rotation of the antenna. The potential sensitivity of this antenna is superior to those of current detectors in a 1 mHz-10 Hz frequency band and is sufficient for observations of gravitational waves radiated from in-spiral and merger events of intermediate-mass black holes.
DECIGO and DECIGO pathfinder 査読有り

Masaki Ando, Seiji Kawamura, Naoki Seto, Shuichi Sato, Takashi Nakamura, Kimio Tsubono, Takeshi Takashima, Ikkoh Funaki, Kenji Numata, Nobuyuki Kanda, Takahiro Tanaka, Kunihito Ioka, Kazuhiro Agatsuma, Koh-suke Aoyanagi, Koji Arai, Akito Araya, Hideki Asada, Yoichi Aso, Takeshi Chiba, Toshikazu Ebisuzaki, Yumiko Ejiri, Motohiro Enoki, Yoshiharu Eriguchi, Masa-Katsu Fujimoto, Ryuichi Fujita, Mitsuhiro Fukushima, Toshifumi Futamase, Tomohiro Harada, Tatsuaki Hashimoto, Kazuhiro Hayama, Wataru Hikida, Yoshiaki Himemoto, Hisashi Hirabayashi, Takashi Hiramatsu, Feng-Lei Hong, Hideyuki Horisawa, Mizuhiko Hosokawa, Kiyotomo Ichiki, Takeshi Ikegami, Kaiki T. Inoue, Koji Ishidoshiro, Hideki Ishihara, Takehiko Ishikawa, Hideharu Ishizaki, Hiroyuki Ito, Yousuke Itoh, Kiwamu Izumi, Isao Kawano, Nobuki Kawashima, Fumiko Kawazoe, Naoko Kishimoto, Kenta Kiuchi, Shiho Kobayashi, Kazunori Kohri, Hiroyuki Koizumi, Yasufumi Kojima, Keiko Kokeyama, Wataru Kokuyama, Kei Kotake, Yoshihide Kozai, Hiroo Kunimori, Hitoshi Kuninaka, Kazuaki Kuroda, Kei-ichi Maeda, Hideo Matsuhara, Yasushi Mino, Osamu Miyakawa, Umpei Miyamoto, Shinji Miyoki, Mutsuko Y. Morimoto, Toshiyuki Morisawa, Shigenori Moriwaki, Shinji Mukohyama, Mitsuru Musha, Shigeo Nagano, Isao Naito, Kouji Nakamura, Masahiro Nakamura, Hiroyuki Nakano, Kenichi Nakao, Shinichi Nakasuka, Yoshinori Nakayama, Kazuhiro Nakazawa, Erina Nishida, Kazutaka Nishiyama, Atsushi Nishizawa, Yoshito Niwa, Taiga Noumi, Yoshiyuki Obuchi, Masatake Ohashi, Naoko Ohishi, Masashi Ohkawa, Kenshi Okada, Norio Okada, Kenichi Oohara, Norichika Sago, Motoyuki Saijo, Ryo Saito, Masaaki Sakagami, Shin-ichiro Sakai, Shihori Sakata, Misao Sasaki, Takashi Sato, Masaru Shibata, Hisaaki Shinkai, Kentaro Somiya, Hajime Sotani, Naoshi Sugiyama, Yudai Suwa, Rieko Suzuki, Hideyuki Tagoshi, Fuminobu Takahashi, Kakeru Takahashi, Keitaro Takahashi, Ryutaro Takahashi, Ryuichi Takahashi, Tadayuki Takahashi, Hirotaka Takahashi, Takamori Akiteru, Tadashi Takano, Keisuke Taniguchi, Atsushi Taruya, Hiroyuki Tashiro, Yasuo Torii, Morio Toyoshima, Shinji Tsujikawa, Yoshiki Tsunesada, Akitoshi Ueda, Ken-ichi Ueda, Masayoshi Utashima, Yaka Wakabayashi, Kent Yagi, Hiroshi Yamakawa, Kazuhiro Yamamoto, Toshitaka Yamazaki, Jun'ichi Yokoyama, Chul-Moon Yoo, Shijun Yoshida, Taizoh Yoshino, Ken-Xun Sun

CLASSICAL AND QUANTUM GRAVITY　27　(8)　084010　2010年4月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0264-9381/27/8/084010 　

ISSN：0264-9381

eISSN：1361-6382

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A space gravitational-wave antenna, DECIGO (DECI-hertz interferometer Gravitational wave Observatory), will provide fruitful insights into the universe, particularly on the formation mechanism of supermassive black holes, dark energy and the inflation of the universe. In the current pre-conceptual design, DECIGO will be comprising four interferometer units; each interferometer unit will be formed by three drag-free spacecraft with 1000 km separation. Since DECIGO will be an extremely challenging mission with high-precision formation flight with long baseline, it is important to increase the technical feasibility before its planned launch in 2027. Thus, we are planning to launch two milestone missions. DECIGO pathfinder (DPF) is the first milestone mission, and key components for DPF are being tested on ground and in orbit. In this paper, we review the conceptual design and current status of DECIGO and DPF.
DECIGO pathfinder 査読有り

Masaki Ando, Seiji Kawamura, Shuichi Sato, Takashi Nakamura, Kimio Tsubono, Akito Araya, Ikkoh Funaki, Kunihito Ioka, Nobuyuki Kanda, Shigenori Moriwaki, Mitsuru Musha, Kazuhiro Nakazawa, Kenji Numata, Shin-ichiro Sakai, Naoki Seto, Takeshi Takashima, Takahiro Tanaka, Kazuhiro Agatsuma, Koh-suke Aoyanagi, Koji Arai, Hideki Asada, Yoichi Aso, Takeshi Chiba, Toshikazu Ebisuzaki, Yumiko Ejiri, Motohiro Enoki, Yoshiharu Eriguchi, Masa-Katsu Fujimoto, Ryuichi Fujita, Mitsuhiro Fukushima, Toshifumi Futamase, Katsuhiko Ganzu, Tomohiro Harada, Tatsuaki Hashimoto, Kazuhiro Hayama, Wataru Hikida, Yoshiaki Himemoto, Hisashi Hirabayashi, Takashi Hiramatsu, Feng-Lei Hong, Hideyuki Horisawa, Mizuhiko Hosokawa, Kiyotomo Ichiki, Takeshi Ikegami, Kaiki T. Inoue, Koji Ishidoshiro, Hideki Ishihara, Takehiko Ishikawa, Hideharu Ishizaki, Hiroyuki Ito, Yousuke Itoh, Nobuki Kawashima, Fumiko Kawazoe, Naoko Kishimoto, Kenta Kiuchi, Shiho Kobayashi, Kazunori Kohri, Hiroyuki Koizumi, Yasufumi Kojima, Keiko Kokeyama, Wataru Kokuyama, Kei Kotake, Yoshihide Kozai, Hideaki Kudoh, Hiroo Kunimori, Hitoshi Kuninaka, Kazuaki Kuroda, Kei-ichi Maeda, Hideo Matsuhara, Yasushi Mino, Osamu Miyakawa, Shinji Miyoki, Mutsuko Y. Morimoto, Tomoko Morioka, Toshiyuki Morisawa, Shinji Mukohyama, Shigeo Nagano, Isao Naito, Kouji Nakamura, Hiroyuki Nakano, Kenichi Nakao, Shinichi Nakasuka, Yoshinori Nakayama, Erina Nishida, Kazutaka Nishiyama, Atsushi Nishizawa, Yoshito Niwa, Taiga Noumi, Yoshiyuki Obuchi, Masatake Ohashi, Naoko Ohishi, Masashi Ohkawa, Norio Okada, Kouji Onozato, Kenichi Oohara, Norichika Sago, Motoyuki Saijo, Masaaki Sakagami, Shihori Sakata, Misao Sasaki, Takashi Sato, Masaru Shibata, Hisaaki Shinkai, Kentaro Somiya, Hajime Sotani, Naoshi Sugiyama, Yudai Suwa, Rieko Suzuki, Hideyuki Tagoshi, Fuminobu Takahashi, Kakeru Takahashi, Keitaro Takahashi, Ryutaro Takahashi, Ryuichi Takahashi, Tadayuki Takahashi, Hirotaka Takahashi, Takamori Akiteru, Tadashi Takano, Keisuke Taniguchi, Atsushi Taruya, Hiroyuki Tashiro, Yasuo Torii, Morio Toyoshima, Shinji Tsujikawa, Yoshiki Tsunesada, Akitoshi Ueda, Ken-ichi Ueda, Masayoshi Utashima, Yaka Wakabayashi, Hiroshi Yamakawa, Kazuhiro Yamamoto, Toshitaka Yamazaki, Jun'ichi Yokoyama, Chul-Moon Yoo, Shijun Yoshida, Taizoh Yoshino

CLASSICAL AND QUANTUM GRAVITY　26　(9)　2009年5月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0264-9381/26/9/094019 　

ISSN：0264-9381

eISSN：1361-6382

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DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory), which is a future space gravitational wave antenna. DECIGO is expected to provide fruitful insights into the universe, particularly about dark energy, the formation mechanism of supermassive black holes and the inflation of the universe. Since DECIGO will be an extremely challenging mission, which will be formed by three drag-free spacecraft with 1000 km separation, it is important to increase the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. In this paper, we review the conceptual design and current status of the first milestone mission, DPF.
Research and Development Status of a New Rotational Seismometer Based on the Flux Pinning Effect of a Superconductor 査読有り

Akiteru Takamori, Akito Araya, Yuji Otake, Koji Ishidoshiro, Masaki Ando

BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA　99　(2B)　1174-1180　2009年5月
出版者・発行元：SEISMOLOGICAL SOC AMER
DOI： 10.1785/0120080087 　

ISSN：0037-1106

eISSN：1943-3573

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Rotational motions induced by earthquakes are expected to contain unique geophysical information not obtainable from translational motions, such as the distribution of slip velocity near the earthquake source. However their observations have not been performed as actively as those of translational motions, mainly because of technical difficulties. Rotational seismometers with sufficient resolution (better than 10(-10) rad/sec/Hz(1/2) over 0.1 mHz to 10 Hz) and reliability at reasonable cost are needed to establish broad observation networks for rotational seismology. To achieve this goal, we are developing a seismometer with a new design based on a proof mass levitated by a magnetic suspension that uses the flux pinning effect of a superconductor to make it freely rotatable without introducing unwanted parasitic resonances and other complexities. Prototype systems were built and tested to assess the feasibility of the technologies used in the new seismometer, and their advantages and capabilities have been successfully demonstrated. The design of the new seismometer together with the status of the development and future plans are presented in this article.
The Japanese space gravitational wave antenna; DECIGO 査読有り

S Kawamura, M Ando, T Nakamura, K Tsubono, T Tanaka, I Funaki, N Seto, K Numata, S Sato, K Ioka, N Kanda, T Takashima, K Agatsuma, T Akutsu, T Akutsu, K-s Aoyanagi, K Arai, Y Arase, A Araya, H Asada, Y Aso, T Chiba, T Ebisuzaki, M Enoki, Y Eriguchi, M-K Fujimoto, R Fujita, M Fukushima, T Futamase, K Ganzu, T Harada, T Hashimoto, K Hayama, W Hikida, Y Himemoto, H Hirabayashi, T Hiramatsu, F-L Hong, H Horisawa, M Hosokawa, K Ichiki, T Ikegami, K T Inoue, K Ishidoshiro, H Ishihara, T Ishikawa, H Ishizaki, H Ito, Y Itoh, S Kamagasako, N Kawashima, F Kawazoe, H Kirihara, N Kishimoto, K Kiuchi, S Kobayashi, K Kohri, H Koizumi, Y Kojima, K Kokeyama, W Kokuyama, K Kotake, Y Kozai, H Kudoh, H Kunimori, H Kuninaka, K Kuroda, K-i Maeda, H Matsuhara, Y Mino, O Miyakawa, S Miyoki, M Y Morimoto, T Morioka, T Morisawa, S Moriwaki, S Mukohyama, M Musha, S Nagano, I Naito, N Nakagawa, K Nakamura, H Nakano, K Nakao, S Nakasuka, Y Nakayama, E Nishida, K Nishiyama, A Nishizawa, Y Niwa, M Ohashi, N Ohishi, M Ohkawa, A Okutomi, K Onozato, K Oohara, N Sago, M Saijo, M Sakagami, S-i Sakai, S Sakata, M Sasaki, T Sato, M Shibata, H Shinkai, K Somiya, H Sotani, N Sugiyama, Y Suwa, H Tagoshi, K Takahashi, K Takahashi, T Takahashi, H Takahashi, R Takahashi, R Takahashi, A Takamori, T Takano, K Taniguchi, A Taruya, H Tashiro, M Tokuda, M Tokunari, M Toyoshima, S Tsujikawa, Y Tsunesada, K-i Ueda, M Utashima, H Yamakawa, K Yamamoto, T Yamazaki, J Yokoyama, C-M Yoo, S Yoshida, T Yoshino

Journal of Physics: Conference Series　120　(3)　032004-032004　2008年7月1日
出版者・発行元：IOP Publishing
DOI： 10.1088/1742-6596/120/3/032004 　

ISSN：1742-6588

eISSN：1742-6596
A systematical veto by all monitor signals in a gravitational-wave detector 査読有り

Koji Ishidoshiro, Masaki Ando, Kimio Tsubono, Nobuyuki Kanda, Hirotaka Takahashi

CLASSICAL AND QUANTUM GRAVITY　24　(19)　S405-S413　2007年10月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0264-9381/24/19/S04 　

ISSN：0264-9381

eISSN：1361-6382

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We present the current state of veto studies in TAMA300 by monitor signals of the interferometer and its environment. In GW data analysis, fake GW events may bury real GW events or worse upper limits on the event rate. Thus, fake-event rejection is an important issue. In general, we can reject these fake events by the monitor signals, since these fake events are induced due to detector instabilities. However, using all monitor signals for the fake-event rejection would increase the accidental rejection probability and dead time without improving veto efficiency, since all monitor signals do not have correlations to the detector instabilities. Here, we analyze coincidences between the main and selected monitor signals with the optimal parameters for the fake-event rejection. Then, coincident events are rejected as the fake events. For the signal selection and parameter optimization, we systematically investigate the correlations with the detector instabilities. As a result, we achieved 30 - 99% veto efficiency using ten selected monitor signals with the 3.2% accidental rejection probability and 0.2% dead time.
The Japanese space gravitational wave antenna - DECIGO 査読有り

Seiji Kawamura, Takashi Nakamura, Masaki Ando, Naoki Seto, Kimio Tsubono, Kenji Numata, Ryuichi Takahashi, Shigeo Nagano, Takehiko Ishikawa, Mitsuru Musha, Ken-ichi Ueda, Takashi Sato, Mizuhiko Hosokawa, Kazuhiro Agatsuma, Tomotada Akutsu, Koh-suke Aoyanagi, Koji Arai, Akito Araya, Hideki Asada, Yoichi Aso, Takeshi Chiba, Toshikazu Ebisuzaki, Yoshiharu Eriguchi, Masa-Katsu Fujimoto, Mitsuhiro Fukushima, Toshifumi Futamase, Katsuhiko Ganzu, Tomohiro Harada, Tatsuaki Hashimoto, Kazuhiro Hayama, Wataru Hikida, Yoshiaki Himemoto, Hisashi Hirabayashi, Takashi Hiramatsu, Kiyotomo Ichiki, Takeshi Ikegami, Kaiki T. Inoue, Kunihito Ioka, Koji Ishidoshiro, Yousuke Itoh, Shogo Kamagasako, Nobuyuki Kanda, Nobuki Kawashima, Hiroyuki Kirihara, Kenta Kiuchi, Shiho Kobayashi, Kazunori Kohri, Yasufumi Kojima, Keiko Kokeyama, Yoshihide Kozai, Hideaki Kudoh, Hiroo Kunimori, Kazuaki Kuroda, Kei-ichi Maeda, Hideo Matsuhara, Yasushi Mino, Osamu Miyakawa, Shinji Miyoki, Hiromi Mizusawa, Toshiyuki Morisawa, Shinji Mukohyama, Isao Naito, Noriyasu Nakagawa, Kouji Nakamura, Hiroyuki Nakano, Atsushi Nishizawa, Yoshito Niwa, Choetsu Nozawa, Masatake Ohashi, Naoko Ohishi, Masashi Ohkawa, Akira Okutomi, Kenichi Oohara, Norichika Sago, Motoyuki Saijo, Masaaki Sakagami, Shihori Sakata, Misao Sasaki, Shuichi Sato, Masaru Shibata, Hisaaki Shinkai, Kentaro Somiya, Hajime Sotani, Naoshi Sugiyama, Hideyuki Tagoshi, Tadayuki Takahashi, Hirotaka Takahashi, Ryutaro Takahashi, Tadashi Takano, Takahiro Tanaka, Keisuke Taniguchi, Atsushi Taruya, Hiroyuki Tashiro, Masao Tokunari, Shinji Tsujikawa, Yoshiki Tsunesada, Kazuhiro Yamamoto, Toshitaka Yamazaki, Jun'ichi Yokoyama, Chul-Moon Yoo, Shijun Yoshida, Taizoh Yoshino

CLASSICAL AND QUANTUM GRAVITY　23　(8)　S125-S131　2006年4月
出版者・発行元：IOP PUBLISHING LTD
DOI： 10.1088/0264-9381/23/8/S17 　

ISSN：0264-9381

eISSN：1361-6382

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DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. It aims at detecting various kinds of gravitational waves between 1 mHz and 100 Hz frequently enough to open a new window of observation for gravitational wave astronomy. The preconceptual design of DECIGO consists of three drag-free satellites, 1000 km apart from each other, whose relative displacements are measured by a Fabry-Perot Michelson interferometer. We plan to launch DECIGO in 2024 after a long and intense development phase, including two pathfinder missions for verification of required technologies.
Systematic survey for monitor signals to reduce fake burst events in a gravitational-wave detector 査読有り

Koji Ishidoshiro, Masaki Ando, Kimio Tsubono

Journal of Physics: Conference Series　32　(1)　23-28　2006年3月2日
出版者・発行元：Institute of Physics Publishing
DOI： 10.1088/1742-6596/32/1/005 　

ISSN：1742-6596 1742-6588

詳細を見る詳細を閉じる

We present methods and results to reduce fake burst events induced by nonstationary noises. To reduce these fake events, we systematically surveyed monitor signals recorded with a main (or gravitational-wave) signal of a gravitational-wave detector so as to watch the detector. Our survey was to check whether or not there was a coincidence between the main and monitor signals when we found a burst event from the main signal. If there was a coincidence, we rejected this event as a fake event induced by nonstationary noises, regarding the main signal as being dominated by nonstationary noises. As a result, we succeeded to reject about 90% of the burst events of which the SNR values were larger than 10 as fake events, with an accidental probability of about 5% to reject burst-gravitational-wave candidates. © 2006 IOP Publishing Ltd.

︎全件表示 ︎最初の5件までを表示

MISC 2

ニュートリノは神の粒子か? − 神岡地下1000 mで進む0νββ発見への挑戦 −

飯田崇史, 尾﨑秀義, 石徹白晃治

高エネルギーニュース　39　(3)　99-109　2020年10月30日
液体シンチレータ型検出器によるニュートリノ天文学・地球科学

石徹白晃治, 渡辺寛子, 竹本康浩

天文月報　113　(10)　610-619　2020年9月

講演・口頭発表等 45

New dark matter search at Kamioka 招待有り

Koji Ishidoshiro

Kashiwa Dark Matter symposium 2022　2022年12月1日
神岡低放射能冷凍機

石徹白晃治

第８回極低放射能技術研究会　2022年11月25日
超伝導センサーを用いた暗黒物質探索招待有り

石徹白晃治

超伝導エレクトロニクス(SCE)研究会　2022年11月15日
KamLANDで探る地球、太陽と宇宙招待有り

石徹白晃治

2022年10月16日
神岡での軽い暗黒物質探索

石徹白晃治

SMART2022　2022年12月17日
Kinetic inductance detectors evaporated on CaF2 for astroparticle physics

Koji Ishidoshiro

IEEE NSS/MIC 2022　2022年11月8日
KamLANDによる前兆ニュートリノを用いた超新星アラームシステムの現状と展望

石徹白晃治

日本天文学会2022年秋季年会　2022年9月13日
KamLAND2へ向けたRFSoCベースのフロントエンド電子回路開発招待有り

石徹白晃治

RCNP研究会「原子核実験の次世代データ収集システム基盤開発にむけて」　2022年5月16日
Kinetic inductance detectors on fluoride crystal for spin-dependent dark matter search 国際会議

石徹白晃治

TAUP2019　2019年9月10日
Kinetic inductance detectors on CaF2 for spin-dependent dark matter search 国際会議

石徹白晃治

LTD18　2019年7月25日
panel 1 国際会議招待有り

石徹白晃治

SNEWS2.0　2019年6月16日
Presupernova neutrino monitor at KamLAND 国際会議招待有り

石徹白晃治

SNEWS2.0　2019年6月15日
Nearby SNe with KamLAND 国際会議

石徹白晃治

Revealing the history of the universe with underground particle and nuclear research 2019　2019年3月9日
Lumped element kinetic inductance detectors on CaF2 for neutrino-less double-beta decay and spin-dependent dark matter search 国際会議

石徹白晃治

VCI2019　2019年2月21日
KamLAND -近傍超新星爆発と電子回路-

石徹白晃治

第五回超新星ニュートリノ研究会　2019年1月7日
Development of new front-end electronics for KamLAND2-Zen 国際会議

石徹白晃治

DBD18　2018年10月21日
液体シンチレータとニュートリノ物理招待有り

石徹白晃治

SMART2018　2018年5月18日
ニュートリノで探る宇宙・素粒子の謎

石徹白晃治

熊本工業高等専門学校出前授業　2018年2月9日
KamLAND

石徹白晃治

第四回超新星ニュートリノ研究会　2018年1月9日
0νββやダークマター探索に生かしたい！招待有り

石徹白晃治

TIAかけはし事業「簡単・便利な超伝導計測」研究会　2018年1月4日
ニュートリノで予報する超新星爆発

石徹白晃治

仙台市天文台×東北大学大学院理学研究科公開サイエンス講座第4回「ニュートリノからさぐる宇宙の謎」　2017年12月10日
無機結晶を基材とした超伝導検出器の開発招待有り

石徹白晃治

SMART2017　2017年11月12日
無ニュートリノ２重ベータ崩壊及び軽い暗黒物質探索を目指した超伝導放射線検出器の開発

石徹白晃治

超伝導エレクトロニクス研究会　2017年10月4日
ニュートリノによる宇宙素粒子物理学

石徹白晃治

広島大学宇宙科学センターセミナー　2017年7月18日
超伝導ボロメータによる0νββ及び軽いDMの探索招待有り

石徹白晃治

2017年度CRC将来計画タウンミーティング　2017年6月24日
ニュートリノによる宇宙素粒子物理学

石徹白晃治

国立天文台談話会 (第982回)　2017年6月23日
超新星前兆ニュートリノ研究招待有り

石徹白晃治

新学術「地下素核研究」2017年領域研究会　2017年5月22日
KamLAND 国際会議招待有り

International workshop on ‘Supernova at Hyper-Kamiokande’　2017年2月13日
pre-supernova neutrino and supernova alarm before collapse 国際会議

Symposium on "New development in astrophysics through multimessenger observations of gravitational wave sources"　2016年12月26日
大型液体シンチレータ検出器による超新星ニュートリノ研究の可能性

天文学会 (2016年春季年会)　2016年3月14日
Revealing the history of the universe with underground particle and nuclear research 招待有り

新学術領域研究「ニュートリノフロンティア」研究会2015　2015年12月1日
Future Supernova neutrino experiments 国際会議

10th International Workshop on Neutrino-Nucleus Interactions in the Few-GeV Region　2015年11月16日
超新星ニュートリノの振動現象とフーリエ解析招待有り

SKE f2f meeting　2015年10月17日
天体活動と超新星ニュートリノ招待有り

重力波天体・地下素核研究・中性子星核物質, 新学術３領域合同シンポジウム「多面的アプローチで解きあかす宇宙と天体」　2015年7月24日
Low-energy Neutrino Astrophysics in KamLAND

KEK physics seminar　2015年6月30日
天体活動と重元素生成の解明へ向けた超新星ニュートリノ観測システムの高度化

「宇宙の歴史をひもとく地下素粒子原子核研究」第二回研究会　2015年5月15日
液シン型検出器による超新星ニュートリノ研究の現状と展望

第一回超新星ニュートリノ研究会　2015年3月15日
KamLAND-Zen 国際会議招待有り

International Workshop on Double Beta Decay and Underground Science (DBD2014)　2014年10月5日
超新星（前兆）ニュートリノ

「宇宙の歴史をひもとく地下素粒子原子核研究」第一回研究会　2014年8月23日
Nearby supernovae with KamLAND 国際会議

2nd Symposium on 'Gravitational Wave Astronomy'　2014年1月13日
KamLAND 国際会議招待有り

14th International Workshop on Next generation Nucleon Decay and Neutrino Detectors　2013年11月11日
Geo-neutrino measurements with KamLAND 国際会議

Goldschmidt2013　2013年8月26日
Image capturing at KamLAND 国際会議

Muon and Neutrino Radiography 2013　2013年7月25日
Cosmic Microwave Background Polarization Results from the QUIET Experiment 国際会議

12th Asia Pacific Physics Conference　2013年7月14日
KamLANDによる超新星ニュートリノの研究

日本物理学会第68回年次大会　2013年3月26日

︎全件表示 ︎最初の5件までを表示

共同研究・競争的資金等の研究課題 14

3次元超伝導検出器が切り拓く究極の宇宙素粒子実験

田井野徹, 石徹白晃治, 美馬覚

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Research (Pioneering)

研究種目：Grant-in-Aid for Challenging Research (Pioneering)

研究機関：Saitama University

2021年7月～ 2025年3月

詳細を見る詳細を閉じる

近年の急速な宇宙観測や加速器実験により宇宙の誕生と進化の様子が解明されつつあるが未解決な最重要課題が存在している。これまでに、我々の体や地球を形作る通常の物質の約５．５倍にもなる暗黒物質が存在することが分かってきた。また宇宙初期には物質と反物質が等量存在していたはずが、今では物質だけの宇宙（物質優勢宇宙）となっている。この謎の扉を開く鍵は「極稀反応の直接測定」にある。世界中で様々な実験が行われているが未だその発見、検出には至っていない暗黒物質、２重β崩壊。極めて希で、極めて小さい反応がその発見を妨げている。本研究では、誰もが望む究極の測定＝バックグランドフリーを可能とし、今までなしえなかった測定結果＝暗黒物質や２重β崩壊の検出から、冒頭の究極的な問いに答えをもたらせる検出器として、３次元超伝導放射線検出器を開発することが目的である。初年度は、読み出しを含めた冷凍機の調整、超伝導検出器として用いる力学インダクタンス検出器（KID）の開発などを行った。読み出しを含めた冷凍機の調整では、冷凍機に付属する装置の故障により1ヶ月ほど冷却試験などが行えなかったものの、検出器を遮蔽するためのシールド材を冷凍機内に設置した状態での冷却試験や本研究で用いるユニークな構造を有する超伝導検出器のためのサンプルホルダを設計し、作製したホルダを冷凍機内に設置、その冷却試験などを行い、冷凍機としての正常動作を確認した。つぎに超伝導検出器の開発では、まず暗黒物質に感度を有する検出器とするため、作製する検出器が集積される基板材料に着目し、複数種類の基板に対してKIDを作製し、その動作確認を行い、基本動作を確認した。また効率的に暗黒物質を検出できるよう、検出器の設計と電磁界シミュレーションを行い、その設計に基づき検出器の試作を行った。
超伝導ナノワイヤーで切り開く極軽量暗黒物質探索の新展開

石徹白晃治

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Research (Exploratory)

研究種目：Grant-in-Aid for Challenging Research (Exploratory)

研究機関：Tohoku University

2022年6月～ 2024年3月
極低温技術による宇宙素粒子研究の高感度化競争的資金

吉田斉

2019年6月～ 2024年3月
軽い暗黒物質探索を目指した超伝導検出器の開発競争的資金

石徹白晃治

2019年4月～ 2021年3月
フッ化物結晶を用いた軽い暗黒物質の探索競争的資金

石徹白晃治

2019年4月～ 2020年3月
地下研究施設国際ネットワークによる宇宙の歴史の解明

井上邦雄, 岸本康宏, 作田誠, 身内賢太朗, 岸本忠史, 石徹白晃司, 竹内康雄, 柳田勉

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research

研究種目：Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

研究機関：Tohoku University

2015年11月6日～ 2019年3月31日

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相乗効果を生み出す技術連携の枠組みを、神岡地下から世界の地下施設に広げる活動を実施した。大型化が課題となり統合が進む暗黒物質探索では、地下素核研究の技術を携えて海外実験に合流し、大幅な性能向上を実現することとなった。また、方向感度を持つ暗黒物質探索では、神岡が世界のハブとして開発をリードしていく体制が作られた。さらに、極低放射能研究の将来技術として注目されている極低温蛍光熱量計開発においては、領域の蛍光結晶技術と韓国の低温熱量計技術を組み合わせた国際連携による開発が進んだ。共通基盤技術開発の国際協調体制が進んだことで、地下での素粒子原子核研究での将来に続くリーダーシップを発揮していく。
宇宙の歴史をひもとく地下素粒子原子核研究

井上邦雄, 柳田勉, 岸本康宏, 作田誠, 竹内康雄, 身内賢太朗, 濱口幸一, 岸本忠史, 石徹白晃治, 吉田斉, 鈴木洋一郎, 中畑雅行

提供機関：Japan Society for the Promotion of Science

制度名：Grants-in-Aid for Scientific Research

研究種目：Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

研究機関：Tohoku University

2014年7月10日～ 2019年3月31日

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神岡地下の素粒子原子核研究が極低放射能を共通基盤として連携し、素粒子的宇宙像理論で橋渡しすることで、宇宙の歴史を系統的に解き明かしてきた。総括班は密接な運営会議・総括班会議によって連携を強く促進できた。特に極低バックグラウンド技術を共有化できたことで、各実験的研究が大幅に進展し世界をリードする成果をあげることができた。同時に、広い分野にまたがった研究対象を共通の技術や関心で取りまとめ新たな領域を定義できたことで、人材の流動性やキャリアパスの増加を生み出すことができた。国内・国際研究会を多数開催し、チュートリアルやパネルディスカッションなども企画することで、領域外も含めた連携を促進できた。
近傍天体ニュートリノ包括的観測体制の構築と天体活動の研究競争的資金

石徹白晃治

2014年7月～ 2019年3月
超伝導ボロメータ技術を用いた高感度マヨラナニュートリノ探索競争的資金

石徹白晃治

2016年4月～ 2018年3月
超伝導検出器を用いた軽い暗黒物質探索競争的資金

石徹白晃治

2016年4月～ 2018年3月
超高感度マヨナラニュートリノ探索競争的資金

石徹白晃治

2013年4月～ 2016年3月
KamLANDによる近傍超新星爆発の観測競争的資金

石徹白晃治

2013年4月～ 2015年3月
重力波実験技術を応用した新しいニュートリノ質量測定方法の開拓競争的資金

石徹白晃治

2013年4月～ 2015年3月
磁気浮上を利用した低周波重力波検出実験

石徹白晃治

2008年～ 2009年

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本年度は、前半に超伝導磁気浮上型ねじれアンテナのロトタイプを開発し、その有効性-実現可能性などを実験的に検証した。その結果、試験質量を回転方向に対して非常に自由(ダンピング定数で1.2±0.7×10^<-8>Nms/rad,バネ定数3.6±2.1×10^<-7>Nm/radで)に支持することに成功した。また、0.2Hzで2×10^<-9>1/rHzという重力波振幅等価雑音の実現にも成功した。この雑音レベルは、他の周波数帯域と比べると必ずしも良くないが、0.1-1Hz帯域では世界成功レベルである。さらに、年度後半に簡易観測運転を行い、観測データを用いて電波パルサーPSR J2144-3933起源の連続重力波と初期宇宙に起源を持つ原始重力波に対する上限値を評価した。特に、このパルサーは、最長の周期8.51秒を持ち、標準のパルサー理論を超える性質を持っている。このようなパルサー起源の重力波探索は、異常パルサーの研究の面からも興味深い。上限値評価の結果、パルサー起源の連続重力波の振幅に対して2.8×10^<-8>の頻度主義的上限値と8.4×10^<-10>のベイズ的な上限値を信頼度95%で得た。原始重力波に対しては、宇宙の臨界密度で規格化された重力波のエネルギ-密度Ωと規格化されたハッブル定数hに対してΩh<8.1x10^<17>の制限を信頼度95%で得た。これらの上限値は他の周波数帯域で既に得られた値と比較して、数桁大きい値であるが、0.1-1Hz帯域の制限は初めてのものであり、既存の上限値と相補的な情報を我々に与えてくれるものである。

︎全件表示 ︎最初の5件までを表示