2025/06/20 更新

写真a

フジイ　トシヒロ
藤井　俊博
FUJII TOSHIHIRO
担当
大学院理学研究科 物理学専攻 准教授
理学部 物理学科
職名
准教授
所属
理学研究院
ホームページ
https://www.omu.ac.jp/sci/uhelab/
所属キャンパス
杉本キャンパス

担当・職階

  • 大学院理学研究科 物理学専攻 

    准教授  2022年04月 - 継続中

  • 理学部 物理学科 

    准教授  2022年04月 - 継続中

取得学位

  • 博士(理学) （ 大阪市立大学 ）

研究分野

  • 自然科学一般 / 天文学

  • 自然科学一般 / 素粒子、原子核、宇宙線、宇宙物理に関する実験

研究キーワード

  • 銀河団

  • 超新星爆発

  • 超新星残骸

  • 起源

  • 空気シャワー

  • 異方性

  • 活動銀河核

  • 極高エネルギー

  • 宇宙線

  • 天文学

  • 大気蛍光

  • 化学組成

  • 中性子星

  • ブラックホール

  • パルサー

  • ニュートリノ

  • ダークマター

  • スペクトル

  • ガンマ線バースト

  • ガンマ線

研究概要

  • 宇宙空間に存在する高エネルギーの放射線「宇宙線」を研究しています。宇宙線の中でも、宇宙磁場でほとんど曲げられない100エクサ電子ボルトを超えるエネルギーをもつ「極高エネルギー宇宙線」を観測することで、その起源および加速機構の解明を目指しています。国際共同実験によって、宇宙線検出器の観測運用や装置開発、データ解析、そして得られた結果の物理的解釈を進めています。

所属学協会

  • 日本物理学会

  • 日本天文学会

受賞歴

  • 公立大学法人大阪 理事長表彰

    藤井俊博

    2024年11月  

  • 第42回（令和6年度）大阪科学賞

    藤井俊博

    2024年09月  

  • 大阪公立大学 南部陽一郎記念若手奨励賞

    藤井俊博

    2024年07月  

  • 大阪公立大学 若手研究者奨励賞 基礎科学部門

    藤井俊博

    2024年07月  

論文

  • Analysis of Inclined Air Shower Events Observed by the TA×4 SD

    Koyama C.

    Proceedings of Science   484   2025年04月

  • Measurement of cosmic-ray energy spectrum with the TALE detector in hybrid mode

    Oshima H.

    Proceedings of Science   484   2025年04月

  • Measurement of cosmic rays with energies down to the PeV region using the TALE-infill SD array

    Kawachi Y.

    Proceedings of Science   484   2025年04月

  • Latest updates and results from the Fluorescence detector Array of Single-pixel Telescopes (FAST)

    Bradfield F.

    Proceedings of Science   484   2025年04月

  • Development of an analysis method for neutrino-induced air showers with the Telescope Array surface detectors

    Takahashi K.

    Proceedings of Science   484   2025年04月

  • Cosmic Ray Composition Measurement between 3 PeV to 30 PeV with the TALE Hybrid Detector

    Fujita K.

    Proceedings of Science   484   2025年04月

  • Calibration of the TA Fluorescence Detectors and Systematic Uncertainties in UHECR Analysis

    Tomida T.

    Proceedings of Science   484   2025年04月

  • Search for the Anomalous Events Detected by ANITA Using the Pierre Auger Observatory

    Abdul Halim A.

    Physical Review Letters   134 ( 12 )   2025年03月（ ISSN:00319007 ）

    　詳細を見る

  • Measurement of the depth of maximum of air-shower profiles with energies between 1018.5 and 1020 eV using the surface detector of the Pierre Auger Observatory and deep learning

    Abdul Halim A.

    Physical Review D   111 ( 2 )   2025年02月（ ISSN:24700010 ）

    　詳細を見る

  • Inference of the Mass Composition of Cosmic Rays with Energies from 1018.5 to 1020 eV Using the Pierre Auger Observatory and Deep Learning

    Abdul Halim A.

    Physical Review Letters   134 ( 2 )   2025年01月（ ISSN:00319007 ）

    　詳細を見る

  • Intermediate Fluence Downward Terrestrial Gamma Ray Flashes as Observed by the Telescope Array Surface Detector

    Abbasi R.U.

    Journal of Geophysical Research Atmospheres   129 ( 24 )   2024年12月（ ISSN:2169-897X ） （ eISSN:2169-8996 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1029/2024JD041260

  • First Time-Resolved Leader Spectra Associated With a Downward Terrestrial Gamma-Ray Flash Detected at the Telescope Array Surface Detector

    Kieu N.

    Journal of Geophysical Research Atmospheres   129 ( 24 )   2024年12月（ ISSN:2169-897X ） （ eISSN:2169-8996 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1029/2024jd041720

  • Impact of the Japanese traditional river training structure “Seigyu (Crib spur dike)” on river morphology and its geometrical changes

    Fujii T.

    Nature Based Solutions   6   2024年12月

    　詳細を見る

  • Monocyte-derived transcriptomes explain the ineffectiveness of abatacept in rheumatoid arthritis

    Iwasaki T.

    Arthritis Research and Therapy   26 ( 1 )   1   2024年12月（ ISSN:14786354 ）

    　詳細を見る

  • A study of the systematic effects on the energy scale for the measurement of UHECR spectrum by the TA SD array

    Fujita K.

    Proceedings of Science   444   2024年09月

  • Updates of the surface detector array of the TAx4 experiment

    Kido E.

    Proceedings of Science   444   2024年09月

  • Update on the searches for anisotropies in UHECR arrival directions with the Pierre Auger Observatory and the Telescope Array

    Caccianiga L.

    Proceedings of Science   444   2024年09月

  • The Surface Array of IceCube-Gen2

    Coleman A.

    Proceedings of Science   444   2024年09月

  • The next generation neutrino telescope: IceCube-Gen2

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • TA SD analysis for inclined air showers

    Takahashi K.

    Proceedings of Science   444   2024年09月

  • Systematic uncertainty in the analysis of the TA fluorescence detector from fluorescence yield models

    Komori K.

    Proceedings of Science   444   2024年09月

  • Shower angular resolution in IceCube-Gen2 and implications on diffuse science

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Sensitivity of the IceCube-Gen2 Surface Array for Cosmic-Ray Anisotropy Studies

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Sensitivity of IceCube-Gen2 to measure flavor composition of Astrophysical neutrinos

    Lad N.

    Proceedings of Science   444   2024年09月

  • Search for EeV photon–induced events at the Telescope Array

    Kharuk I.

    Proceedings of Science   444   2024年09月

  • Science with the Global Cosmic-ray Observatory (GCOS)

    Batista R.A.

    Proceedings of Science   444   2024年09月

  • Reconstruction procedure of the Fluorescence detector Array of Single-pixel Telescopes (FAST)

    Bradfield F.

    Proceedings of Science   444   2024年09月

  • Possible interpretations of the joint observations of UHECR arrival directions using data recorded at the Telescope Array and the Pierre Auger Observatory

    Kuznetsov M.

    Proceedings of Science   444   2024年09月

  • Performance studies on new 4" photomultiplier types intended for IceCube-Gen2 optical modules

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Performance Studies of the Acoustic Module for the IceCube Upgrade

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Monocular and Hybrid Analysis for TA×4 Fluorescence Detectors

    Kusumori Y.

    Proceedings of Science   444   2024年09月

  • Mechanical design of the optical modules intended for IceCube-Gen2

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Measurement of UHECR energy spectrum with the Pierre Auger Observatory and the Telescope Array

    Bergman D.R.

    Proceedings of Science   444   2024年09月

  • Measurement of the cosmic ray energy spectrum with the TA×4 SD array

    Fujisue K.

    Proceedings of Science   444   2024年09月

  • Measurement of the cosmic ray energy spectrum in the 2nd knee region with the TALE-SD array

    Komae I.

    Proceedings of Science   444   2024年09月

  • Measurement of cosmic-ray energy spectrum with the TALE detector in hybrid mode

    Oshima H.

    Proceedings of Science   444   2024年09月

  • ISAI, Investigating Solar Axion by Iron-57: the commissioning and the first run

    Onuki Y.

    Proceedings of Science   444   2024年09月

  • Investigating multiple ELVES and halos above strong lightning with the fluorescence detectors of the Pierre Auger Observatory

    Mussa R.

    Proceedings of Science   444   2024年09月

  • Influence of Galactic magnetic fields on UHECR energy spectrum and mass composition on the Earth

    Higuchi R.

    Proceedings of Science   444   2024年09月

  • Highlights from the Telescope Array Experiment

    Kim J.

    Proceedings of Science   444   2024年09月

  • High-speed Video Camera Observations Associated with a Terrestrial Gamma-ray Flash at the Telescope Array Detector.

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Estimating the coincidence rate between the optical and radio array of IceCube-Gen2

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Electronics Design of the IceCube-Gen2 Optical Module Prototype

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Effects of atmospheric transparency on Telescope Array air shower analysis

    Mizuno K.

    Proceedings of Science   444   2024年09月

  • Effect of optical properties of FDs on reconstruction analysis

    Sato D.

    Proceedings of Science   444   2024年09月

  • Direction reconstruction for the in-ice radio array of IceCube-Gen2

    Nelles A.

    Proceedings of Science   444   2024年09月

  • Development of a general purpose air shower simulation tool COSMOS X

    Sako T.

    Proceedings of Science   444   2024年09月

  • Detecting ultra-high-energy cosmic rays with prototypes of the Fluorescence detector Array of Single-pixel Telescopes (FAST) in both hemispheres

    Sakurai S.

    Proceedings of Science   444   2024年09月

  • Depth of maximum of air-shower profiles: testing the compatibility of the measurements at the Pierre Auger Observatory and the Telescope Array

    Yushkov A.

    Proceedings of Science   444   2024年09月

  • Deep Learning Based Event Reconstruction for the IceCube-Gen2 Radio Detector

    Abbasi R.

    Proceedings of Science   444   2024年09月

  • Cosmic-ray and gamma-ray constraints on very-heavy dark matter decay

    Das S.

    Proceedings of Science   444   2024年09月

  • Cosmic ray mass composition measurement with the TALE hybrid detector

    Fujita K.

    Proceedings of Science   444   2024年09月

  • Cosmic Ray Energy Spectrum and Mass Composition measured by the TALE Fluorescence Detector

    AbuZayyad T.

    Proceedings of Science   444   2024年09月

  • Auger@TA: An Auger-like surface detector micro-array embedded within the Telescope Array Project

    Mayotte S.

    Proceedings of Science   444   2024年09月

  • Anisotropies in the Arrival Direction Distribution of Ultra-High Energy Cosmic Rays Measured by the Telescope Array Surface Detector

    Kim J.

    Proceedings of Science   444   2024年09月

  • テレスコープアレイ実験による史上最大級のエネルギーをもつ宇宙線「アマテラス粒子」の検出

    藤井 俊博, 木戸 英治, 樋口 諒, 藤田 慧太郎

    日本物理学会誌   79 ( 9 )   507 - 511   2024年09月（ ISSN:00290181 ） （ eISSN:24238872 ）

    　詳細を見る

    <p>2021年5月27日，244エクサ電子ボルト（＝244 EeV＝2.44×10<sup>20</sup> eV）という観測史上最大級のエネルギーをもつ宇宙線「アマテラス粒子」が米国ユタ州で検出された．この粒子はたったひとつの粒子であるにもかかわらず，40 Wの電球を1秒点灯できるという巨視的なエネルギーをもつ．仮に1グラムあれば日本全体の年間電気使用量（約1,000テラワット時）を約1,000万年もまかなうことができるという，とてつもないエネルギーである．宇宙にはこのような高いエネルギーをもつ粒子が存在し，地球に絶えず降り注いでいる．これまでの観測で，10<sup>8</sup> eVから10<sup>20</sup> eVを超える幅広いエネルギーの宇宙線が地球で検出されている．あるエネルギー以上の宇宙線の到来頻度は，エネルギーが10倍になると約1/100に減少する．100 EeV以上の宇宙線は1 km<sup>2</sup>あたりに300年にたった1粒子しか到来しないため，検出には広大な検出面積と装置の長期運用が必要である．この100 EeVを超えるエネルギーをもつ極高エネルギー宇宙線は，地球でもっとも大きい粒子加速器で到達できるエネルギーより7桁以上も大きく，宇宙でもっとも高いエネルギーをもつ粒子である．極高エネルギー宇宙線がどこで生まれ，どのように地球にやってきたのかについては未だ明らかになっていない．</p><p>極高エネルギー宇宙線がどこからやってきたのかを明らかにするため，世界9か国/地域の国際共同宇宙線観測実験，テレスコープアレイ実験がはじまった．テレスコープアレイ実験は，面積3 m<sup>2</sup>のプラスチックシンチレーターを1.2 km間隔で507台設置した地表粒子検出器アレイであり，700 km<sup>2</sup>の面積にやってくる極高エネルギー宇宙線の観測を2008年から続けている．これまで15年以上の定常観測の中で，もっとも高いエネルギーをもつ宇宙線が冒頭で紹介したアマテラス粒子である．アマテラス粒子は，地球大気に入射したあと大気との相互作用によって二次粒子群（空気シャワー）を生成し，23台の地表粒子検出器でほぼ同時に信号が検出された．それぞれの検出器で記録された空気シャワーの到来時間差と粒子数密度から，アマテラス粒子の到来方向とエネルギーが推定された．</p><p>アマテラス粒子のような極めて高いエネルギーをもつ宇宙線は，宇宙磁場ではほとんど曲げられず，到来方向が発生源をさししめすことが期待されていた．しかし，驚くべきことにアマテラス粒子の到来方向には有力な候補天体が見あたらず，わたしたちのいる天の川銀河の近傍の大規模構造では局所的空洞（ローカルボイド）と呼ばれる方向から到来していた．極高エネルギー宇宙線の発生源としては，大質量ブラックホールをもつ，おとめ座銀河団にある楕円銀河（M87）や，星形成が非常に活動的な銀河（M82）が候補天体として考えられていたが，それらのどの方向とも異なっていたのである．このことの説明には，不定性の大きい宇宙磁場を仮定した天体起源シナリオの議論のほか，未知の天体現象，暗黒物質（ダークマター）の崩壊やモノポールといった新物理起源の可能性も提案されている．</p>

    DOI： 10.11316/butsuri.79.9_507

  • Isotropy of Cosmic Rays beyond 1020 eV Favors Their Heavy Mass Composition

    Abbasi R.U.

    Physical Review Letters   133 ( 4 )   041001   2024年07月（ ISSN:0031-9007 ） （ eISSN:1079-7114 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1103/PhysRevLett.133.041001

    PubMed

  • Mass composition of ultrahigh energy cosmic rays from distribution of their arrival directions with the Telescope Array

    Abbasi R.U.

    Physical Review D   110 ( 2 )   2024年07月（ ISSN:2470-0010 ） （ eISSN:2470-0029 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1103/PhysRevD.110.022006

  • Testing hadronic-model predictions of depth of maximum of air-shower profiles and ground-particle signals using hybrid data of the Pierre Auger Observatory

    Abdul Halim A.

    Physical Review D   109 ( 10 )   2024年05月（ ISSN:24700010 ）

    　詳細を見る

  • Energy landscape analysis and time-series clustering analysis of patient state multistability related to rheumatoid arthritis drug treatment: The KURAMA cohort study

    Yamamoto K.

    Plos One   19 ( 5 May )   e0302308   2024年05月

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  • Constraints on metastable superheavy dark matter coupled to sterile neutrinos with the Pierre Auger Observatory

    Abdul Halim A.

    Physical Review D   109 ( 8 )   2024年04月（ ISSN:24700010 ）

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  • Commissioning and the first observation of ISAI, Investigating Solar Axion by Iron-57, experiment

    Onuki Y.

    Proceedings of Science   441   2024年03月

  • The past and future 20-years endeavor for discovering origins of ultra-high energy cosmic rays – Rapporteur’s summary of cosmic ray indirect – OA

    Fujii T.

    Proceedings of Science   444   2024年01月

    　詳細を見る

  • Radio measurements of the depth of air-shower maximum at the Pierre Auger Observatory

    Abdul Halim A.

    Physical Review D   109 ( 2 )   2024年01月（ ISSN:24700010 ）

    　詳細を見る

  • Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory

    Abdul Halim A.

    Physical Review Letters   132 ( 2 )   2024年01月（ ISSN:00319007 ）

    　詳細を見る

  • Constraining models for the origin of ultra-high-energy cosmic rays with a novel combined analysis of arrival directions, spectrum, and composition data measured at the Pierre Auger Observatory

    Abdul Halim A.

    Journal of Cosmology and Astroparticle Physics   2024 ( 1 )   2024年01月

    　詳細を見る

  • Observing cosmic-ray extensive air showers with a silicon imaging detector

    Kawanomoto S.

    Scientific Reports   13 ( 1 )   16091   2023年12月

    　詳細を見る

  • An extremely energetic cosmic ray observed by a surface detector array.

    Telescope Array Collaboration*†, Abbasi RU, Allen MG, Arimura R, Belz JW, Bergman DR, Blake SA, Shin BK, Buckland IJ, Cheon BG, Fujii T, Fujisue K, Fujita K, Fukushima M, Furlich GD, Gerber ZR, Globus N, Hibino K, Higuchi R, Honda K, Ikeda D, Ito H, Iwasaki A, Jeong S, Jeong HM, Jui CH, Kadota K, Kakimoto F, Kalashev OE, Kasahara K, Kawata K, Kharuk I, Kido E, Kim SW, Kim HB, Kim JH, Kim JH, Komae I, Kubota Y, Kuznetsov MY, Lee KH, Lubsandorzhiev BK, Lundquist JP, Matthews JN, Nagataki S, Nakamura T, Nakazawa A, Nonaka T, Ogio S, Ono M, Oshima H, Park IH, Potts M, Pshirkov S, Remington JR, Rodriguez DC, Rott C, Rubtsov GI, Ryu D, Sagawa H, Sakaki N, Sako T, Sakurai N, Shin H, Smith JD, Sokolsky P, Stokes BT, Stroman TS, Takahashi K, Takeda M, Taketa A, Tameda Y, Thomas S, Thomson GB, Tinyakov PG, Tkachev I, Tomida T, Troitsky SV, Tsunesada Y, Udo S, Urban FR, Wong T, Yamazaki K, Yuma Y, Zhezher YV, Zundel Z

    Science (New York, N.Y.)   382 ( 6673 )   903 - 907   2023年11月（ ISSN:0036-8075 ） （ eISSN:1095-9203 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1126/science.abo5095

    PubMed

  • The energy spectrum of cosmic rays measured by the Telescope Array using 10 years of fluorescence detector data

    Abbasi R.U.

    Astroparticle Physics   151   102864 - 102864   2023年09月（ ISSN:0927-6505 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1016/j.astropartphys.2023.102864

  • First High-Speed Video Camera Observations of a Lightning Flash Associated With a Downward Terrestrial Gamma-Ray Flash

    Abbasi R.U.

    Geophysical Research Letters   50 ( 14 )   2023年07月（ ISSN:0094-8276 ） （ eISSN:1944-8007 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1029/2023GL102958

  • Effects of the Galactic Magnetic Field on the UHECR Correlation Studies with Starburst Galaxies

    Higuchi R.

    Astrophysical Journal   949 ( 2 )   107 - 107   2023年06月（ ISSN:0004-637X ） （ eISSN:1538-4357 ）

    　詳細を見る

    掲載種別：研究論文（学術雑誌）  

    DOI： 10.3847/1538-4357/acc739

    その他URL： https://iopscience.iop.org/article/10.3847/1538-4357/acc739/pdf

  • Revisiting ultrahigh-energy constraints on decaying superheavy dark matter

    Das S.

    Physical Review D   107 ( 10 )   2023年05月（ ISSN:24700010 ）

    　詳細を見る

  • Constraining the sources of ultra-high-energy cosmic rays across and above the ankle with the spectrum and composition data measured at the Pierre Auger Observatory

    Abdul Halim A.

    Journal of Cosmology and Astroparticle Physics   2023 ( 5 )   2023年05月

    　詳細を見る

  • Ultra high energy cosmic rays The intersection of the Cosmic and Energy Frontiers

    Coleman A.

    Astroparticle Physics   147   2023年05月（ ISSN:09276505 ）

    　詳細を見る

  • Performance of the TALE infill experiment as a TA-TALE extension down to the PeV region

    Aoi Iwasaki, Keitaro Fujita, Shoichi Ogio, Toshihiro Fujii, Yoshiki Tsunesada

    EPJ Web of Conferences   283   06015 - 06015   2023年04月（ eISSN:2100-014X ）

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    掲載種別：研究論文（学術雑誌）  

    The TALE infill experiment is a further extension of TA-TALE detectors to observe low-energy cosmic rays down to the PeV region. TALE infill utilizes the existing TALE-FD detectors, and newly developed "infill" surface detectors with 100 m and 200 m spacing. The new detectors will be deployed at the TALE site in October-November 2022. We present the design and performance of the TALE infill array in the hybrid mode, in terms of the resolutions and biases of arrival direction, energy, and X<sub>max</sub>.

    DOI： 10.1051/epjconf/202328306015

  • The energy spectrum of ultra-high energy cosmic rays measured at the Pierre Auger Observatory and the Telescope Array

    D. R. Bergman, O. Deligny, F. Fenu, T. Fujii, K. Fujita, J. H. Kim, I. Lhenry-Yvon, I. Maris¸, Q. Luce, M. Roth, F. Salamida, Y. Tsunesada, V. Verzi

    EPJ Web of Conferences   283   02003 - 02003   2023年04月（ eISSN:2100-014X ）

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    掲載種別：研究論文（学術雑誌）  

    In the study of cosmic rays, the measurement of the energy spectrum of the primaries is one of the main issues and provides fundamental information on the most energetic phenomena in the Universe. At ultrahigh energies, beyond 10<sup>18</sup> eV, the cosmic rays are studied by the two largest observatories built so far, the Pierre Auger Observatory and the Telescope Array. Both observatories are based on a hybrid design and reported a measurement of the energy spectrum using the high duty cycle of the surface detector and the calorimetric estimation of the energy scale provided by the fluorescence detector.

    The differences among the reported spectra are scrutinized by a working group made by members of the Pierre Auger and Telescope Array Collaborations. The two measurements have been found well in agreement below 10<sup>19</sup> eV while, at higher energies, they show an energy-dependent difference that is beyond the systematic uncertainties associated to the energy scale.

    In this contribution we review the status and perspectives of the working group activities including new studies aiming at addressing the impact on the flux measurement at the highest energies of potential biases in the estimation of the shower size.

    DOI： 10.1051/epjconf/202328302003

  • Effects of Galactic magnetic field on the UHECR anisotropy studies

    Ryo Higuchi, Takashi Sako, Kazumasa Kawata, Toshihiro Fujii, Eiji Kido, R. U. Abbasi, T. Abu-Zayyad, M. Allen, Y. Arai, R. Arimura, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, I. Buckland, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, R. Gonzalez, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, A. Iwasaki, H. M. Jeong, S. Jeong, C. C.H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, I. Kharuk, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, Y. Kubota, S. Kurisu, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, T. Nakamura, Y. Nakamura, A. Nakazawa, E. Nishio, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. Potts, M. S. Pshirkov

    Proceedings of Science   395   2022年03月（ eISSN:1824-8039 ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    Telescope Array (TA) and Auger experiments reported anisotropies in the arrival direction of ultrahigh-energy cosmic rays (UHECRs). In particular, Auger Collaboration reported a correlation between UHECR events and the flux model of assumed sources and suggested a contribution of starburst galaxies (SBGs) to the anisotropy of UHECRs. However, in their study, the effect of coherent deflections by the galactic magnetic field (GMF) is not taken into account. In this study, we investigated the effect of the GMF on the arrival directions of UHECRs using the cosmic ray propagation code CRPropa3. We used a backtracking technique which consists of propagating antiparticles to map the flux outside the galaxy to at the earth. We estimate the systematic effects caused by GMF in the reported likelihood analysis. We conduct likelihood analysis for mock UHECR datasets based on the flux pattern through the GMF model. We found systematic decrease of (fani, θ) due to GMF. As prospects for the TAx4 experiment and joint analysis of Auger and TA collaborations, we develop the likelihood analysis method with the convolution of the rigidity spectrum.

  • Telescope Array search for EeV photons

    Oleg E. Kalashev, Ivan V. Kharuk, Mikhail Yu Kuznetsov, Grigory I. Rubtsov, R. U. Abbasi, T. Abu-Zayyad, M. Allen, Y. Arai, R. Arimura, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, I. Buckland, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, R. Gonzalez, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, A. Iwasaki, H. M. Jeong, S. Jeong, C. C.H. Jui, K. Kadota, F. Kakimoto, O. Kalshev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, Z. Zundel, E. Kido, H. B. Kim, J. H. Kim, J. A. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, Y. Kubota, S. Kurisu, V. Kuzmin, Y. Zhezher, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, T. Nakamora, Y. Nakamura, A. Nakazawa, E. Nishio, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. Potts, M. S. Pshirkov

    Proceedings of Science   395   2022年03月（ eISSN:1824-8039 ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    We present updated results of the search for the ultra-high energy photons with primary energies greater than 10 EeV. The data of the Telescope Array Surface Detector collected over 11 years are used in this work. The method is based on the machine learning classifier, which is trained on both the reconstructed composition-sensitive parameters of the event and the calibrated waveform signals at each triggered station of the Surface Detector.

  • Hotspot Update, and a new Excess of Events on the Sky Seen by the Telescope Array Experiment

    Jihyun Kim, Dmitri Ivanov, Kazumasa Kawata, Hiroyuki Sagawa, Gordon Thomson, R. U. Abbasi, T. Abu-Zayyad, M. Allen, Y. Arai, R. Arimura, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, I. Buckland, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, R. Gonzalez, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, A. Iwasaki, H. M. Jeong, S. Jeong, C. C.H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, I. Kharuk, E. Kido, H. B. Kim, J. H. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, Y. Kubota, S. Kurisu, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, T. Nakamura, Y. Nakamura, A. Nakazawa, E. Nishio, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. Potts, M. S. Pshirkov

    Proceedings of Science   395   2022年03月（ eISSN:1824-8039 ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    The Telescope Array (TA) experiment, the largest observatory studying ultrahigh energy cosmic rays in the northern hemisphere, has reported an excess in the arrival direction distribution for events with energies above 5.7 × 1019 eV, called the hotspot. We report here the latest results of the TA hotspot using the most recent data measured by the TA surface detector array, which is more than doubled exposure since the first publication; the hotspot still exists with 3 sigma post-trial significance. By using an oversampling search with a 20◦-circle, similar to the study of the hotspot, we find an additional excess of events at slightly lower energies. The Perseus-Pisces supercluster lies at the location of the new excess. Assuming this structure is responsible for the excess, we conducted a statistical analysis to verify the correlation between observed events and the members of the Perseus-Pisces supercluster.

  • Observation of variations in cosmic ray single count rates during thunderstorms and implications for large-scale electric field changes

    R. U. Abbasi, T. Abu-Zayyad, M. Allen, Y. Arai, R. Arimura, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, I. Buckland, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, N. Globus, R. Gonzalez, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, N. Husseini, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, A. Iwasaki, H. M. Jeong, S. Jeong, H. Johnson, C. C.H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, I. Kharuk, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, Y. Kubota, S. Kurisu, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, R. Levon, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, J. Mazich, M. Minamino, K. Mukai, I. Myers, P. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, T. Nakamura, Y. Nakamura, A. Nakazawa, E. Nishio, T. Nonaka, K. O'Brien, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa

    Physical Review D   105 ( 6 )   2022年03月（ ISSN:2470-0010 ） （ eISSN:2470-0029 ）

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    掲載種別：研究論文（学術雑誌）  

    We present the first observation by the Telescope Array Surface Detector (TASD) of the effect of thunderstorms on the development of cosmic ray single count rate intensity over a 700 km2 area. Observations of variations in the secondary low-energy cosmic ray counting rate, using the TASD, allow us to study the electric field inside thunderstorms, on a large scale, as it progresses on top of the 700 km2 detector, without dealing with the limitation of narrow exposure in time and space using balloons and aircraft detectors. In this work, variations in the cosmic ray intensity (single count rate) using the TASD, were studied and found to be on average at the ~(0.5-1)% and up to 2% level. These observations were found to be both in excess and in deficit. They were also found to be correlated with lightning in addition to thunderstorms. These variations lasted for tens of minutes; their footprint on the ground ranged from 6 km to 24 km in diameter and moved in the same direction as the thunderstorm. With the use of simple electric field models inside the cloud and between cloud to ground, the observed variations in the cosmic ray single count rate were recreated using CORSIKA simulations. Depending on the electric field model used and the direction of the electric field in that model, the electric field magnitude that reproduces the observed low-energy cosmic ray single count rate variations was found to be approximately between 0.2 GV-0.4 GV. This in turn allows us to get a reasonable insight on the electric field and its effect on cosmic ray air showers inside thunderstorms.

    DOI： 10.1103/PhysRevD.105.062002

  • Ultra-High-Energy Cosmic Rays: The Intersection of the Cosmic and Energy Frontiers

    Coleman, A., Eser, J., Mayotte, E., Sarazin, F., Schröder, F. G., Soldin, D., Venters, T. M., Aloisio, R., Alvarez-Muñiz, J., Batista, R. Alves, Bergman, D., Bertaina, M., Caccianiga, L., Deligny, O., Dembinski, H. P., Denton, P. B., di Matteo, A., Globus, N., Glombitza, J., Golup, G., Haungs, A., Hör, el, J. R., Jaffe, T. R., Kelley, J. L., Krizmanic, J. F., Lu, L., Matthews, J. N., Mariş, I., Mussa, R., Oikonomou, F., Pierog, T., Santos, E., Tinyakov, P., Tsunesada, Y., Unger, M., Yushkov, A., Albrow, M. G., Anchordoqui, L. A., Andeen, K., Arnone, E., Barghini, D., Bechtol, E., Bellido, J. A., Casolino, M., Castellina, A., Cazon, L., Conceição, R., Cremonini, R., Dujmovic, H., Engel, R., Farrar, G., Fenu, F., Ferrarese, S., Fujii, T., Gardiol, D., Gritsevich, M., Homola, P., Huege, T., Kampert, K. -H., Kang, D., Kido, E., Klimov, P., Kotera, K., Kozelov, B., Leszczyńska, A., Madsen, J., Marcelli, L., Marisaldi, M., Martineau-Huynh, O., Mayotte, S., Mulrey, K., Murase, K., Muzio, M. S., Ogio, S., Olinto, A. V., Onel, Y., Paul, T., Piotrowski, L., Plum, M., Pont, B., Reininghaus, M., Riedel, B., Riehn, F., Roth, M., Sako, T., Schlüter, F., Shoemaker, D., Sidhu, J., Sidelnik, I., Timmermans, C., Tkachenko, O., Veberič, D., Verpoest, S., Verzi, V., Vícha, J., Winn, D., Zas, E., Zotov, M.

    2022年

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    掲載種別：研究論文（学術雑誌）  

    The present white paper is submitted as part of the "Snowmass" process to help inform the long-term plans of the United States Department of Energy and the National Science Foundation for high-energy physics. It summarizes the science questions driving the Ultra-High-Energy Cosmic-Ray (UHECR) community and provides recommendations on the strategy to answer them in the next two decades.

    DOI： 10.48550/ARXIV.2205.05845

  • Surface detectors of the TAx4 experiment

    R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, Y. Arai, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, Kuzmin, V, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, Myers, I, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, K. Saito, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, K. Sato, T. Seki, K. Sekino, P. D. Shah, F. Shibata, N. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, D. Shinto, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, Tkachev, I, H. Tokuno, T. Tomida, S. Troitsky, R. Tsuda, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, T. Wong, K. Yada, M. Yamamoto, K. Yamazaki, J. Yang, K. Yashiro, F. Yoshida, Y. Zhezher, Z. Zundel

    NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT   1019   2021年12月（ ISSN:0168-9002 ） （ eISSN:1872-9576 ）

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    掲載種別：研究論文（学術雑誌）  

    Telescope Array (TA) is the largest ultrahigh energy cosmic-ray (UHECR) observatory in the Northern Hemisphere. It explores the origin of UHECRs by measuring their energy spectrum, arrival-direction distribution, and mass composition using a surface detector (SD) array covering approximately 700 km(2) and fluorescence detector (FD) stations. TA has found evidence for a cluster of cosmic rays with energies greater than 57 EeV. In order to confirm this evidence with more data, it is necessary to increase the data collection rate. We have begun building an expansion of TA that we call TAx4. In this paper, we explain the motivation, design, technical features, and expected performance of the TAx4 SD. We also present TAx4's current status and examples of the data that have already been collected.

    DOI： 10.1016/j.nima.2021.165726

  • The status of the TALE surface detector array and TALE infill project

    Shoichi Ogio, Rasha Abbasi, Tareq Abu-Zayyad, Monica Allen, Yuto Arai, Ryuhei Arimura, Elliott Barcikowski, John Belz, Douglas Bergman, Samuel Blake, Robert Cady, ByongGu Cheon, Jyunsei Chiba, Michiyuki Chikawa, Toshihiro Fujii, Kozo Fujisue, Keitaro Fujita, Ryota Fujiwara, Masaki Fukushima, Ryota Fukushima, Greg Furlich, Noemie Globus, Ricardo Gonzalez, William Hanlon, Motoki Hayashi, Naoaki Hayashida, Kinya Hibino, Ryo Higuchi, Ken Honda, Daisuke Ikeda, Taichi Inadomi, Naoya Inoue, Takaaki Ishii, Hirotaka Ito, Dmitri Ivanov, Hirokazu Iwakura, Aoi Iwasaki, Hyoming Jeong, Soomin Jeong, Charlie Jui, Kenichi Kadota, Fumio Kakimoto, Oleg Kalashev, Katsuaki Kasahara, Saori Kasami, Hideyuki Kawai, Saburo Kawakami, Shingo Kawana, Katsumasa Kawata, Ivan Kharuk, Eiji Kido, HangBae Kim, Jihee Kim, Jihyun Kim, Min Hyo Kim, Sang Woo Kim, Yusuke Kimura, Shoichi Kishigami, Yuto Kubota, Shinnosuke Kurisu, Vladim Kuzmin, Mikhail Kuznetsov, Youngjoon Kwon, Kwangho Lee, BayarJon Paul Lubsandorzhiev, Jon Paul Lundquist, Kazuhiro Machida, Hiroyuki Matsumiya, Toshio Matsuyama, John Matthews, Rosa Mayta, Mayuko Minamino, Keijiro Mukai, Isaac Myers, Shigehiro Nagataki, Kei Nakai, Ryo Nakamura, Toru Nakamura, Tomoyuki Nakamura, Yuya Nakamura, Arata Nakazawa, Eiji Nishio, Toshiyuki Nonaka, Hiroyuki Oda, Munehiro Ohnishi, Hideyuki Ohoka, Yuya Oku, Takeshi Okuda, Yugo Omura, Masaomi Ono, Ryota Onogi, Akitoshi Oshima, Shunsuke OZAWA, Il Hung Park, Matt Potts, Maxim Pshirkov, Jackson Remington, Doug Rodriguez, Grigory Rubtsov, Dongsu Ryu, Hiroyuki Sagawa, Ryosuke Sahara, Yasunori Saito, Naoto Sakaki, Takashi Sako, Nobuyuki Sakurai, Kengo Sano, Koki Sato, Terutsugu Seki, Koichi Sekino, Priti Shah, Yuma Shibasaki, Fumiya Shibata, Norimichi Shibata, Tatsunobu Shibata, Hideaki Shimodaira, Bokkyun Shin, Heungsu Shin, Daiki Shinto, Jeremy Smith, Pierre Sokolsky, Naohiro Sone, Ben Stokes, Tom Stroman, Yoshinori Takagi, Yuichi Takahashi, Mai Takamura, Masahiro Takeda, Ryuji Takeishi, Akimichi Taketa, Masato Takita, Yuichiro Tameda, Hideki Tanaka, Koichi Tanaka, Manobu Tanaka, Yuta Tanoue, Stanton Thomas, Gordon Thomson, Petr Tinyakov, Igor Tkachev, Hisono Tokuno, Taka Tomida, Sergey Troitsky, Ryosuke Tsuda, Yoshiki Tsunesada, Yukio Uchihori, Shigeharu Udo, Takafumi Uehama, Federico Urban, Tiffany Wong, Kohei Yada, Mashu Yamamoto, Katsuya Yamazaki, Jongmann Yang, Kenta Yashiro, Fugo Yoshida, Tsubasa Yoshioka, Yana Zhezher, Zach Zundel

    Proceedings of 37th International Cosmic Ray Conference — PoS(ICRC2021)   2021年07月

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    掲載種別：研究論文（国際会議プロシーディングス）  

    DOI： 10.22323/1.395.0255

  • Observations of the Origin of Downward Terrestrial Gamma‐Ray Flashes

    J. W. Belz, P. R. Krehbiel, J. Remington, M. A. Stanley, R. U. Abbasi, R. LeVon, W. Rison, D. Rodeheffer, T. Abu‐Zayyad, M. Allen, E. Barcikowski, D. R. Bergman, S. A. Blake, M. Byrne, R. Cady, B. G. Cheon, M. Chikawa, A. Matteo, T. Fujii, K. Fujita, R. Fujiwara, M. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, Y. Hayashi, N. Hayashida, K. Hibino, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, V. Kuzmin†, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, J. N. Matthews, T. Matuyama, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, A. Oshima, S. Ozawa, I. H. Park, M. Potts, M. S. Pshirkov, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, K. Saito, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, T. Seki, K. Sekino, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, Y. Takagi, Y. Takahashi, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, M. Wallace, T. Wong, M. Yamamoto, H. Yamaoka, K. Yamazaki, K. Yashiro, M. Yosei, H. Yoshii, Y. Zhezher, Z. Zundel

    Journal of Geophysical Research: Atmospheres   125 ( 23 )   2020年12月（ ISSN:2169-897X ） （ eISSN:2169-8996 ）

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    掲載種別：研究論文（学術雑誌）  

    Abstract

    In this paper we report the first close, high‐resolution observations of downward‐directed terrestrial gamma‐ray flashes (TGFs) detected by the large‐area Telescope Array cosmic ray observatory, obtained in conjunction with broadband VHF interferometer and fast electric field change measurements of the parent discharge. The results show that the TGFs occur during strong initial breakdown pulses (IBPs) in the first few milliseconds of negative cloud‐to‐ground and low‐altitude intracloud flashes and that the IBPs are produced by a newly identified streamer‐based discharge process called fast negative breakdown. The observations indicate the relativistic runaway electron avalanches (RREAs) responsible for producing the TGFs are initiated by embedded spark‐like transient conducting events (TCEs) within the fast streamer system and potentially also by individual fast streamers themselves. The TCEs are inferred to be the cause of impulsive sub‐pulses that are characteristic features of classic IBP sferics. Additional development of the avalanches would be facilitated by the enhanced electric field ahead of the advancing front of the fast negative breakdown. In addition to showing the nature of IBPs and their enigmatic sub‐pulses, the observations also provide a possible explanation for the unsolved question of how the streamer to leader transition occurs during the initial negative breakdown, namely, as a result of strong currents flowing in the final stage of successive IBPs, extending backward through both the IBP itself and the negative streamer breakdown preceding the IBP.

    DOI： 10.1029/2019jd031940

    その他URL： https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2019JD031940

  • Measurement of the proton-air cross section with Telescope Array’s Black Rock Mesa and Long Ridge fluorescence detectors, and surface array in hybrid mode

    R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, A. di Matteo, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, R. Ishimori, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, S. Kishigami, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, T. Seki, K. Sekino, P. D. Shah, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, T. Wong, K. Yada, M. Yamamoto, K. Yamazaki, J. Yang, K. Yashiro, M. Yosei, Y. Zhezher, Z. Zundel

    Physical Review D   102 ( 6 )   2020年09月（ ISSN:2470-0010 ） （ eISSN:2470-0029 ）

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  • Evidence for a Supergalactic Structure of Magnetic Deflection Multiplets of Ultra-high-energy Cosmic Rays

    R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, A. di Matteo, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, R. Ishimori, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, S. Kishigami, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, T. Seki, K. Sekino, P. D. Shah, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, T. Wong, K. Yada, M. Yamamoto, K. Yamazaki, J. Yang, K. Yashiro, M. Yosei, Y. Zhezher, Z. Zundel

    The Astrophysical Journal   899 ( 1 )   86 - 86   2020年08月（ eISSN:1538-4357 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.3847/1538-4357/aba26c

    その他URL： https://iopscience.iop.org/article/10.3847/1538-4357/aba26c

  • Search for Ultra-High-Energy Neutrinos with the Telescope Array Surface Detector

    R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, A. di Matteo, T. Fujii, K. Fujita, R. Fujiwara, M. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, Y. Hayashi, N. Hayashida, K. Hibino, K. Honda, D. Ikeda, N. Inoue, T. Ishii, R. Ishimori, H. Ito, D. Ivanov, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, S. Kishigami, S. Kitamura, Y. Kitamura, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, K. Martens, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, K. Nagasawa, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, T. Nonaka, H. Oda, S. Ogio, J. Ogura, M. Ohnishi, H. Ohoka, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, K. Saito, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, L. M. Scott, T. Seki, K. Sekino, P. D. Shah, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, B. T. Stokes, S. R. Stratton, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, K. Tsutsumi, Y. Uchihori, S. Udo, F. Urban, T. Wong, K. Yada, M. Yamamoto, H. Yamaoka, K. Yamazaki, J. Yang, K. Yashiro, H. Yoshii, Y. Zhezher, Z. Zundel

    Journal of Experimental and Theoretical Physics   131 ( 2 )   255 - 264   2020年08月（ ISSN:1063-7761 ） （ eISSN:1090-6509 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1134/s106377612005012x

    その他URL： http://link.springer.com/article/10.1134/S106377612005012X/fulltext.html

  • Search for Large-scale Anisotropy on Arrival Directions of Ultra-high-energy Cosmic Rays Observed with the Telescope Array Experiment

    R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, A. di Matteo, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, R. Ishimori, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, S. Kishigami, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, T. Seki, K. Sekino, P. D. Shah, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, T. Wong, K. Yada, M. Yamamoto, K. Yamazaki, J. Yang, K. Yashiro, M. Yosei, Y. Zhezher, Z. Zundel

    The Astrophysical Journal   898 ( 2 )   L28 - L28   2020年07月（ eISSN:2041-8213 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.3847/2041-8213/aba0bc

    その他URL： https://iopscience.iop.org/article/10.3847/2041-8213/aba0bc

  • Search for point sources of ultra-high-energy photons with the Telescope Array surface detector

    R U Abbasi, M Abe, T Abu-Zayyad, M Allen, R Azuma, E Barcikowski, J W Belz, D R Bergman, S A Blake, R Cady, B G Cheon, J Chiba, M Chikawa, A di Matteo, T Fujii, K Fujita, R Fujiwara, M Fukushima, G Furlich, W Hanlon, M Hayashi, Y Hayashi, N Hayashida, K Hibino, K Honda, D Ikeda, N Inoue, T Ishii, R Ishimori, H Ito, D Ivanov, H M Jeong, S Jeong, C C H Jui, K Kadota, F Kakimoto, O Kalashev, K Kasahara, H Kawai, S Kawakami, S Kawana, K Kawata, E Kido, H B Kim, J H Kim, J H Kim, S Kishigami, V Kuzmin, M Kuznetsov, Y J Kwon, K H Lee, B Lubsandorzhiev, J P Lundquist, K Machida, K Martens, T Matsuyama, J N Matthews, R Mayta, M Minamino, K Mukai, I Myers, S Nagataki, K Nakai, R Nakamura, T Nakamura, T Nonaka, H Oda, S Ogio, M Ohnishi, H Ohoka, T Okuda, Y Omura, M Ono, R Onogi, A Oshima, S Ozawa, I H Park, M S Pshirkov, J Remington, D C Rodriguez, G Rubtsov, D Ryu, H Sagawa, R Sahara, K Saito, Y Saito, N Sakaki, T Sako, N Sakurai, L M Scott, T Seki, K Sekino, P D Shah, F Shibata, T Shibata, H Shimodaira, B K Shin, H S Shin, J D Smith, P Sokolsky, B T Stokes, S R Stratton, T A Stroman, T Suzawa, Y Takagi, Y Takahashi, M Takamura, M Takeda, R Takeishi, A Taketa, M Takita, Y Tameda, H Tanaka, K Tanaka, M Tanaka, Y Tanoue, S B Thomas, G B Thomson, P Tinyakov, I Tkachev, H Tokuno, T Tomida, S Troitsky, Y Tsunesada, K Tsutsumi, Y Uchihori, S Udo, F Urban, T Wong, K Yada, M Yamamoto, H Yamaoka, K Yamazaki, J Yang, K Yashiro, H Yoshii, Y Zhezher, Z Zundel

    Monthly Notices of the Royal Astronomical Society   492 ( 3 )   3984 - 3993   2020年03月（ ISSN:0035-8711 ） （ eISSN:1365-2966 ）

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    掲載種別：研究論文（学術雑誌）  

    <title>ABSTRACT</title>
    The surface detector (SD) of the Telescope Array (TA) experiment allows us to detect indirectly photons with energies of the order of 1018 eV and higher, and to separate photons from the cosmic ray background. In this paper, we present the results of a blind search for point sources of ultra-high-energy (UHE) photons in the Northern sky using the TA SD data. The photon-induced extensive air showers are separated from the hadron-induced extensive air shower background by means of a multivariate classifier based upon 16 parameters that characterize the air shower events. No significant evidence for the photon point sources is found. The upper limits are set on the flux of photons from each particular direction in the sky within the TA field of view, according to the experiment’s angular resolution for photons. The average 95 per cent confidence level upper-limits for the point-source flux of photons with energies greater than 1018, 1018.5, 1019, 1019.5 and 1020 eV are 0.094, 0.029, 0.010, 0.0073 and 0.0058 km−2yr−1, respectively. For energies higher than 1018.5 eV, the photon point-source limits are set for the first time. Numerical results for each given direction in each energy range are provided as a supplement to this paper.

    DOI： 10.1093/mnras/stz3618

  • ПОИСК НЕЙТРИНО УЛЬТРАВЫСОКИХ ЭНЕРГИЙ ПО ДАННЫМ НАЗЕМНОЙ РЕШЕТКИ ЭКСПЕРИМЕНТА TELESCOPE ARRAY

    R. U. ABBASI, M. ABE, T. ABU-ZAYYAD, M. ALLEN, R. AZUMA, E. BARCIKOWSKI, J. W. BELZ, D. R. BERGMAN, S. A. BLAKE, R. CADY, B. G. CHEON, J. CHIBA, M. CHIKAWA, A. DI MATTEO, T. FUJII, K. FUJITA, R. FUJIWARA, M. FUKUSHIMA, G. FURLICH, W. HANLON, M. HAYASHI, Y. HAYASHI, N. HAYASHIDA, K. HIBINO, K. HONDA, D. IKEDA, N. INOUE, T. ISHII, R. ISHIMORI, H. ITO, D. IVANOV, H. M. JEONG, S. JEONG, C. C. H. JUI, K. KADOTA, F. KAKIMOTO, O. KALASHEV, K. KASAHARA, H. KAWAI, S. KAWAKAMI, S. KAWANA, K. KAWATA, E. KIDO, H. B. KIM, JI HEE KIM, JIHYUN KIM, S. KISHIGAMI, S. KITAMURA, Y. KITAMURA, V. KUZMIN, M. KUZNETSOV, Y. J. KWON, K. H. LEE, B. LUBSANDORZHIEV, J. P. LUNDQUIST, K. MACHIDA, K. MARTENS, T. MATSUYAMA, J. N. MATTHEWS, R. MAYTA, M. MINAMINO, K. MUKAI, I. MYERS, K. NAGASAWA, S. NAGATAKI, K. NAKAI, R. NAKAMURA, T. NAKAMURA, T. NONAKA, H. ODA, S. OGIO, J. OGURA, M. OHNISHI, H. OHOKA, T. OKUDA, Y. OMURA, M. ONO, R. ONOGI, A. OSHIMA, S. OZAWA, I. H. PARK, M. S. PSHIRKOV, J. REMINGTON, D. C. RODRIGUEZ, G. RUBTSOV, D. RYU, H. SAGAWA, R. SAHARA, K. SAITO, Y. SAITO, N. SAKAKI, T. SAKO, N. SAKURAI, L. M. SCOTT, T. SEKI, K. SEKINO, P. D. SHAH, F. SHIBATA, T. SHIBATA, H. SHIMODAIRA, B. K. SHIN, H. S. SHIN, J. D. SMITH, P. SOKOLSKY, B. T. STOKES, S. R. STRATTON, T. A. STROMAN, T. SUZAWA, Y. TAKAGI, Y. TAKAHASHI, M. TAKAMURA, M. TAKEDA, R. TAKEISHI, A. TAKETA, M. TAKITA, Y. TAMEDA, H. TANAKA, K. TANAKA, M. TANAKA, Y. TANOUE, S. B. THOMAS, G. B. THOMSON, P. TINYAKOV, I. TKACHEV, H. TOKUNO, T. TOMIDA, S. TROITSKY, Y. TSUNESADA, K. TSUTSUMI, Y. UCHIHORI, S. UDO, F. URBAN, T. WONG, K. YADA, M. YAMAMOTO, H. YAMAOKA, K. YAMAZAKI, J. YANG, K. YASHIRO, H. YOSHII, Y. ZHEZHER, Z. ZUNDEL

    ЖУРНАЛ ЭКСПЕРИМЕНТАЛЬНОЙ И ТЕОРЕТИЧЕСКОЙ ФИЗИКИ   158 ( 2(8) )   282 - 294   2020年（ ISSN:0044-4510 ）

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.31857/s0044451020080052

  • Ultra-violet imaging of the night-time earth by EUSO-Balloon towards space-based ultra-high energy cosmic ray observations 査読

    G. Abdellaoui, S. Abe, J. H. Adams, A. Ahriche, D. Allard, L. Allen, G. Alonso, L. Anchordoqui, A. Anzalone, Y. Arai, K. Asano, R. Attallah, H. Attoui, M. Ave Pernas, S. Bacholle, M. Bakiri, P. Baragatti, P. Barrillon, S. Bartocci, J. Bayer, B. Beldjilali, T. Belenguer, N. Belkhalfa, R. Bellotti, A. Belov, K. Belov, K. Benmessai, M. Bertaina, P. L. Biermann, S. Biktemerova, F. Bisconti, N. Blanc, J. Błȩcki, S. Blin-Bondil, P. Bobik, M. Bogomilov, E. Bozzo, S. Briz, A. Bruno, K. S. Caballero, F. Cafagna, D. Campana, J. N. Capdevielle, F. Capel, A. Caramete, L. Caramete, P. Carlson, R. Caruso, M. Casolino, C. Cassardo, A. Castellina, C. Catalano, O. Catalano, A. Cellino, M. Chikawa, G. Chiritoi, M. J. Christl, V. Connaughton, L. Conti, G. Cordero, G. Cotto, H. J. Crawford, R. Cremonini, S. Csorna, A. Cummings, S. Dagoret-Campagne, A. J. de Castro, C. De Donato, C. de la Taille, C. De Santis, L. del Peral, M. Di Martino, A. Diaz Damian, T. Djemil, I. Dutan, A. Ebersoldt, T. Ebisuzaki, R. Engel, J. Eser, F. Fenu, S. Fernández-González, S. Ferrarese, M. Flamini, C. Fornaro, M. Fouka, A. Franceschi, S. Franchini, C. Fuglesang, T. Fujii, J. Fujimoto, M. Fukushima, P. Galeotti, E. García-Ortega, G. Garipov, E. Gascón, J. Genci, G. Giraudo, C. González Alvarado, P. Gorodetzky, R. Greg

    Astroparticle Physics   111   54 - 71   2019年09月（ ISSN:0927-6505 ）

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    掲載種別：研究論文（学術雑誌）  

    © 2018 The JEM-EUSO (Joint Experiment Missions for the Extreme Universe Space Observatory) program aims at developing Ultra-Violet (UV) fluorescence telescopes for efficient detections of Extensive Air Showers (EASs) induced by Ultra-High Energy Cosmic Rays (UHECRs) from satellite orbit. In order to demonstrate key technologies for JEM-EUSO, we constructed the EUSO-Balloon instrument that consists of a ∼1 m 2 refractive telescope with two Fresnel lenses and an array of multi-anode photo-multiplier tubes at the focus. Distinguishing it from the former balloon-borne experiments, EUSO-Balloon has the capabilities of single photon counting with a gate time of 2.3 µs and of imaging with a total of 2304 pixels. As a pathfinder mission, the instrument was launched for an 8 h stratospheric flight on a moonless night in August 2014 over Timmins, Canada. In this work, we analyze the count rates over ∼2.5 h intervals. The measurements are of diffuse light, e.g. of airglow emission, back-scattered from the Earth's atmosphere as well as artificial light sources. Count rates from such diffuse light are a background for EAS detections in future missions and relevant factor for the analysis of EAS events. We also obtain the geographical distribution of the count rates over a ∼780 km 2 area along the balloon trajectory. In developed areas, light sources such as the airport, mines, and factories are clearly identified. This demonstrates the correct location of signals that will be required for the EAS analysis in future missions. Although a precise determination of count rates is relevant for the existing instruments, the absolute intensity of diffuse light is deduced for the limited conditions by assuming spectra models and considering simulations of the instrument response. Based on the study of diffuse light by EUSO-Balloon, we also discuss the implications for coming pathfinders and future space-based UHECR observation missions.

    DOI： 10.1016/j.astropartphys.2018.10.008

  • The Auger@TA Project: Phase II Progress and Plans

    Corbin Covault, Toshihiro Fujii, Robert Halliday, Jeffrey Johnsen, Ryan Lorek, Toshiyuki Nonaka, Sean Quinn, Hiroyuki Sagawa, Takashi Sako, Fred Sarazin, Ricardo Satos, David Schmidt, Ryuji Takeishi

    ULTRA HIGH ENERGY COSMIC RAYS 2018 (UHECR 2018)   210   2019年（ ISSN:2100-014X ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    The Auger@TA project is a combined effort involving members of both the Pierre Auger Observatory and the Telescope Array experiment (TA) to cross-calibrate detectors and compare results on air showers detected at one location. We have recently reported results from Phase I of the project, during which we collected and presented data from two Auger water Cherenkov surface detector stations deployed into the TA experiment near the Central Laser Facility. For Phase II, we will deploy a micro-array of six or seven single-PMT Auger surface detector stations co-located with TA scintillator surface detector stations. The Auger micro-array will trigger and collect data independently from the TA allowing for a complete end-to-end comparison of detector data, calibration, and reconstructed event quantities on a shower-by-shower basis between the TA and Auger detector systems. We describe progress towards development of the micro-array for Phase II including the preparation of surface detector water tanks, station electronics, wireless communications, triggers, and data acquisition. We also outline plans for deploying the Auger@TA micro-array into the TA experiment in 2019 with preliminary estimates for coincident air-shower rates.

    DOI： 10.1051/epjconf/201921005004

  • TA Anisotropy Summary

    K. Kawata, A. di Matteo, T. Fujii, D. Ivanov, C.C.H. Jui, J.P. Lundquist, J.N. Matthews, S. Ogio, H. Sagawa, G.B. Thomson, P. Tinyakov, I. Tkachev, S. Troitsky

    EPJ Web of Conferences   210   01004 - 01004   2019年（ eISSN:2100-014X ）

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    掲載種別：研究論文（学術雑誌）  

    The Telescope Array (TA) is the largest ultra-high-energy cosmic-ray (UHECR) detector in the northern hemisphere. It consists of an array of 507 surface detectors (SD) covering a total 700 km<sup>2</sup> and three fluorescence detector stations overlooking the SD array. In this proceedings, we summarize recent results on the search for directional anisotropy of UHECRs using the latest dataset collected by the TA SD array. We obtained hints of the anisotropy of the UHECRs in the northern sky from the various analyses.

    DOI： 10.1051/epjconf/201921001004

  • Overview of the Auger@TA project and preliminary results from Phase I

    Fred Sarazin, Corbin Covault, Toshihiro Fujii, Robert Halliday, Jeffrey Johnsen, Ryan Lorek, Toshiyuki Nonaka, Sean Quinn, Hiroyuki Sagawa, Takashi Sako, Ricardo Sato, David Schmidt, Ryuji Takeishi

    ULTRA HIGH ENERGY COSMIC RAYS 2018 (UHECR 2018)   210   2019年（ ISSN:2100-014X ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    We report on the first results of a unique in-situ experimental cross-calibration effort of the surface detector of the Pierre Auger Observatory and of the Telescope Array experiment (Auger@TA). In the first phase of Auger@TA, we performed surface detector station-to-station comparisons for a collection of extensive air showers landing near the experimental setup and detected by Telescope Array. Beyond the deduced cross-calibration curve between the Water-Cherenkov-based Auger and Scintillator-based TA Surface Detector stations, we also investigate the consistency of their response for individual reconstructed showers. The dataset is currently too small to draw firm conclusions as-of-yet. Hence, phase I data taking will continue even as we gear up for the deployment of an Auger micro-array within Telescope Array as part of Phase II of this work.

    DOI： 10.1051/epjconf/201921005002

  • Mass composition of ultrahigh-energy cosmic rays with the Telescope Array Surface Detector data 査読

    Abbasi, R.U., Abe, M., Abu-Zayyad, T., Allen, M., Azuma, R., Barcikowski, E., Belz, J.W., Bergman, D.R., Blake, S.A., Cady, R., Cheon, B.G., Chiba, J., Chikawa, M., Di Matteo, A., Fujii, T., Fujita, K., Fukushima, M., Furlich, G., Goto, T., Hanlon, W., Hayashi, M., Hayashi, Y., Hayashida, N., Hibino, K., Honda, K., Ikeda, D., Inoue, N., Ishii, T., Ishimori, R., Ito, H., Ivanov, D., Jeong, H.M., Jeong, S., Jui, C.C.H., Kadota, K., Kakimoto, F., Kalashev, O., Kasahara, K., Kawai, H., Kawakami, S., Kawana, S., Kawata, K., Kido, E., Kim, H.B., Kim, J.H., Kim, J.H., Kishigami, S., Kitamura, S., Kitamura, Y., Kuzmin, V., Kuznetsov, M., Kwon, Y.J., Lee, K.H., Lubsandorzhiev, B., Lundquist, J.P., Machida, K., Martens, K., Matsuyama, T., Matthews, J.N., Mayta, R., Minamino, M., Mukai, K., Myers, I., Nagasawa, K., Nagataki, S., Nakamura, R., Nakamura, T., Nonaka, T., Oda, H., Ogio, S., Ogura, J., Ohnishi, M., Ohoka, H., Okuda, T., Omura, Y., Ono, M., Onogi, R., Oshima, A., Ozawa, S., Park, I.H., Piskunov, M.S., Pshirkov, M.S., Remington, J., Rodriguez, D.C., Rubtsov, G., Ryu, D., Sagawa, H., Sahara, R., Saito, K., Saito, Y., Sakaki, N., Sakurai, N., Scott, L.M., Seki, T., Sekino, K., Shah, P.D., Shibata, F., Shibata, T., Shimodaira, H., Shin, B.K., Shin, H.S., Smith, J.D., Sokolsky, P., Stokes, B.T., Stratton, S.R., Stroman, T.A., Suzawa, T., Takagi, Y., Takahashi, Y., Takamura, M., Takeda, M., Takeishi, R., Taketa, A., Takita, M., Tameda, Y., Tanaka, H., Tanaka, K., Tanaka, M., Thomas, S.B., Thomson, G.B., Tinyakov, P., Tkachev, I., Tokuno, H., Tomida, T., Troitsky, S., Tsunesada, Y., Tsutsumi, K., Uchihori, Y., Udo, S., Urban, F., Wong, T., Yada, K., Yamamoto, M., Yamane, R., Yamaoka, H., Yamazaki, K., Yang, J., Yashiro, K., Yoneda, Y., Yoshida, S., Yoshii, H., Zhezher, Y., Zundel, Z.

    Physical Review D   99 ( 2 )   2019年

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1103/PhysRevD.99.022002

  • Constraints on the diffuse photon flux with energies above 10 <sup>18</sup> eV using the surface detector of the Telescope Array experiment 査読

    Abbasi, R.U., Abe, M., Abu-Zayyad, T., Allen, M., Azuma, R., Barcikowski, E., Belz, J.W., Bergman, D.R., Blake, S.A., Cady, R., Cheon, B.G., Chiba, J., Chikawa, M., di Matteo, A., Fujii, T., Fujita, K., Fukushima, M., Furlich, G., Goto, T., Hanlon, W., Hayashi, M., Hayashi, Y., Hayashida, N., Hibino, K., Honda, K., Ikeda, D., Inoue, N., Ishii, T., Ishimori, R., Ito, H., Ivanov, D., Jeong, H.M., Jeong, S., Jui, C.C.H., Kadota, K., Kakimoto, F., Kalashev, O., Kasahara, K., Kawai, H., Kawakami, S., Kawana, S., Kawata, K., Kido, E., Kim, H.B., Kim, J.H., Kishigami, S., Kitamura, S., Kitamura, Y., Kuzmin, V., Kuznetsov, M., Kwon, Y.J., Lee, K.H., Lubsandorzhiev, B., Lundquist, J.P., Machida, K., Martens, K., Matsuyama, T., Matthews, J.N., Mayta, R., Minamino, M., Mukai, K., Myers, I., Nagasawa, K., Nagataki, S., Nakamura, R., Nakamura, T., Nonaka, T., Oda, H., Ogio, S., Ogura, J., Ohnishi, M., Ohoka, H., Okuda, T., Omura, Y., Ono, M., Onogi, R., Oshima, A., Ozawa, S., Park, I.H., Piskunov, M.S., Pshirkov, M.S., Remington, J., Rodriguez, D.C., Rubtsov, G.I., Ryu, D., Sagawa, H., Sahara, R., Saito, K., Saito, Y., Sakaki, N., Sakurai, N., Scott, L.M., Seki, T., Sekino, K., Shah, P.D., Shibata, F., Shibata, T., Shimodaira, H., Shin, B.K., Shin, H.S., Smith, J.D., Sokolsky, P., Stokes, B.T., Stratton, S.R., Stroman, T.A., Suzawa, T., Takagi, Y., Takahashi, Y., Takamura, M., Takeda, M., Takeishi, R., Taketa, A., Takita, M., Tameda, Y., Tanaka, H., Tanaka, K., Tanaka, M., Thomas, S.B., Thomson, G.B., Tinyakov, P., Tkachev, I., Tokuno, H., Tomida, T., Troitsky, S., Tsunesada, Y., Tsutsumi, K., Uchihori, Y., Udo, S., Urban, F., Wong, T., Yamamoto, M., Yamane, R., Yamaoka, H., Yamazaki, K., Yang, J., Yashiro, K., Yoneda, Y., Yoshida, S., Yoshii, H., Zhezher, Y., Zundel, Z.

    Astroparticle Physics   110   2019年

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    掲載種別：研究論文（学術雑誌）  

    DOI： 10.1016/j.astropartphys.2019.03.003

  • Updated results on the UHECR hotspot observed by the telescope array experiment

    K. Kawata, A. di Matteo, T. Fujii, D. Ikeda, D. Ivanov, C. C.H. Jui, E. Kido, J. P. Lundquist, J. N. Matthews, S. Nagataki, T. Nonaka, S. Ogio, T. Okuda, G. Rubtsov, H. Sagawa, T. Sako, N. Sakurai, M. Takeda, R. Takeishi, A. Taketa, G. B. Thomson, P. Tinyakov, I. Tkachev, S. Troitsky

    Proceedings of Science   358   2019年（ eISSN:1824-8039 ）

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    掲載種別：研究論文（国際会議プロシーディングス）  

    The Telescope Array Experiment has observed an indication of intermediate-scale anisotropy in the UHECR arrival directions, called the Hotspot, with E > 57 EeV around the Ursa Major using the first 5-year data during a period between May 2008 and May 2013 collected by the TA surface detector array. The chance probability of this hotspot in an isotropic cosmic-ray sky was calculated to be 3.4s (post trial). In this paper, we will report on an update of this result using the 11-year data collected by the TA surface detectors with more than doubled exposure since the first publication.

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MISC（その他記事）

  • FAST実験 10:南北半球での新型大気蛍光望遠鏡による最高エネルギー宇宙線観測

    YOO S., 藤井俊博, 窪秀利, 野崎誠也, 岡知彦, 寺内健太, 武多昭道, MALACARI M., ALBURY J., BELLIDO J.A., CHYTKA L., FARMER J., HAMAL P., HORVATH P., HRABOVSKY M., KVITA J., MANDAT D., MASTRODICASA M., MATTHEWS J.N., MICHAL S., NI X., NOZKA L., PALATKA M., PECH M., PRIVITERA P., SCHOVANEK P., SALAMIDA F., SMIDA R., THOMAS S.B., TRAVNICEK P., VACULA M.

    日本物理学会講演概要集(CD-ROM)   75 ( 2 )   2020年（ ISSN:2189-079X ）

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  • 新型大気蛍光望遠鏡による極高エネルギー宇宙線の観測状況及び波形収集回路の開発

    寺内健太, 藤井俊博, 窪秀利, 野崎誠也, 岡知彦, YOO Seokhyun, 武多昭道, SMIDA Radomir, PRIVITERA Paolo, NI Xiaochen, MALACARI Max, FARMER John, ALBURY Justin, BELLIDO Jose A., TRAVNICEK Petr, SCHOVANEK Petr, PECH Miroslav, NOZKA Libor, PALATKA Miroslav, MICHAL Stanislav, MANDAT Dusan, CHYTKA Ladislav, HAMAL Petr, VACULA Martin, HORVATH Pavel, HRABOVSKY Miroslav, KVITA Jiri, SALAMIDA Francesco, MASTRODICASA Massimo, MATTHEWS John N., THOMAS Stan B.

    日本天文学会年会講演予稿集   2020   2020年（ ISSN:1347-0639 ）

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講演・口頭発表等

  • Hunting origins of ultrahigh-energy cosmic rays 招待

    Toshihiro Fujii

    Nucleosynthesis and Evolution of Neutron Stars  2025年01月 

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    会議種別：口頭発表（招待・特別）  

  • Statistical methods for observing ultrahigh-energy cosmic rays 招待

    Toshihiro Fujii

    Workshop: Data Oriented Astronomy  2024年10月 

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    会議種別：口頭発表（招待・特別）  

  • Visualizing high energy particles of extensive air showers with Subaru Hyper Supreme-Cam

    Toshihiro Fujii

    Workshop on Cosmic Indicators of Dark Matter 2024  2024年10月 

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    会議種別：口頭発表（一般）  

  • The 100-year endeavor for detecting the highest energy cosmic rays 招待

    Toshihiro Fuji

    TeV Particle Astrophysics 2024  2024年08月 

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    会議種別：口頭発表（招待・特別）  

  • Searching for the Universe's most energetic particles 招待

    Toshihiro Fujii

    20th Anniversary of the KICP Celebration  2024年06月 

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    会議種別：口頭発表（招待・特別）  

科研費獲得実績

  • 新型大気蛍光望遠鏡による極高エネルギー宇宙線観測実験の相互較正

    基盤研究(A)  2025年

  • すばる望遠鏡を利用した宇宙線空気シャワー粒子の超精密観測

    挑戦的研究(萌芽)  2025年

  • すばる望遠鏡を利用した宇宙線空気シャワー粒子の超精密観測

    挑戦的研究(萌芽)  2024年

  • マルチメッセンジャーで探る重いダークマター

    学術変革領域研究(A)  2024年

  • 新型ピクセル型シリコン検出器による極低バックグラウンド環境での太陽アクシオン探査

    挑戦的研究(開拓)  2024年

  • 新型大気蛍光望遠鏡アレイによる極高エネルギー宇宙線天文学の開拓

    基盤研究(A)  2024年

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担当授業科目

  • 物理実験学A

    2024年度   週間授業   大学

  • 専門物理学実験A

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  • 物理学特別研究2A

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  • 物理学特別研究1A

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  • 物理学特別演習2A

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  • 物理学特別演習1A

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  • 物理学特別研究5A

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  • 物理学特別研究4A

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  • 物理学特別研究3A

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  • 物理学特別演習5A

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  • 物理学特別演習4A

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  • 物理学特別演習3A

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  • 専門物理学実験B

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  • 海外特別研究1

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  • 物理学特別研究2B

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  • 物理学特別研究1B

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  • 物理学特別演習2B

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  • 物理学特別演習1B

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  • 海外特別研究5

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  • 海外特別研究5

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  • 物理学特別研究5B

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  • 物理学特別研究4B

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  • 物理学特別演習5B

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  • 物理学特別演習4B

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  • 物理学特別演習3B

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  • 海外特別研究

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  • 物理学講読

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  • 特別実験・特別理論演習

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  • 専門物理学実験

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  • 物理実験学

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