Direct Measurement of the Spectral Structure of Cosmic-Ray Electrons+Positrons in the TeV Region with CALET on the International Space Station.

Autor: Adriani O; Department of Physics, University of Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Akaike Y; Waseda Research Institute for Science and Engineering, Waseda University, 17 Kikuicho, Shinjuku, Tokyo 162-0044, Japan.; JEM Utilization Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan., Asano K; Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8582, Japan., Asaoka Y; Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8582, Japan., Berti E; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; Institute of Applied Physics (IFAC), National Research Council (CNR), Via Madonna del Piano, 10, 50019, Sesto Fiorentino, Italy., Bigongiari G; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Binns WR; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA., Bongi M; Department of Physics, University of Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Brogi P; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Bruno A; Heliospheric Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA., Buckley JH; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA., Cannady N; Center for Space Sciences and Technology, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, USA.; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Center for Research and Exploration in Space Sciences and Technology, NASA/GSFC, Greenbelt, Maryland 20771, USA., Castellini G; Institute of Applied Physics (IFAC), National Research Council (CNR), Via Madonna del Piano, 10, 50019, Sesto Fiorentino, Italy., Checchia C; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Cherry ML; Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803, USA., Collazuol G; Department of Physics and Astronomy, University of Padova, Via Marzolo, 8, 35131 Padova, Italy.; INFN Sezione di Padova, Via Marzolo, 8, 35131 Padova, Italy., de Nolfo GA; Heliospheric Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA., Ebisawa K; Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210, Japan., Ficklin AW; Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803, USA., Fuke H; Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210, Japan., Gonzi S; Department of Physics, University of Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; Institute of Applied Physics (IFAC), National Research Council (CNR), Via Madonna del Piano, 10, 50019, Sesto Fiorentino, Italy., Guzik TG; Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803, USA., Hams T; Center for Space Sciences and Technology, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, USA., Hibino K; Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama, Kanagawa 221-8686, Japan., Ichimura M; Faculty of Science and Technology, Graduate School of Science and Technology, Hirosaki University, 3, Bunkyo, Hirosaki, Aomori 036-8561, Japan., Ioka K; Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan., Ishizaki W; Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8582, Japan., Israel MH; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA., Kasahara K; Department of Electronic Information Systems, Shibaura Institute of Technology, 307 Fukasaku, Minuma, Saitama 337-8570, Japan., Kataoka J; School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan., Kataoka R; National Institute of Polar Research, 10-3, Midori-cho, Tachikawa, Tokyo 190-8518, Japan., Katayose Y; Faculty of Engineering, Division of Intelligent Systems Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama 240-8501, Japan., Kato C; Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621, Japan., Kawanaka N; Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan., Kawakubo Y; Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803, USA., Kobayashi K; Waseda Research Institute for Science and Engineering, Waseda University, 17 Kikuicho, Shinjuku, Tokyo 162-0044, Japan.; JEM Utilization Center, Human Spaceflight Technology Directorate, Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba, Ibaraki 305-8505, Japan., Kohri K; Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki, 305-0801, Japan., Krawczynski HS; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA., Krizmanic JF; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA., Maestro P; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Marrocchesi PS; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Messineo AM; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy.; University of Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Mitchell JW; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA., Miyake S; Department of Electrical and Electronic Systems Engineering, National Institute of Technology (KOSEN), Ibaraki College, 866 Nakane, Hitachinaka, Ibaraki 312-8508, Japan., Moiseev AA; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Center for Research and Exploration in Space Sciences and Technology, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA., Mori M; Department of Physical Sciences, College of Science and Engineering, Ritsumeikan University, Shiga 525-8577, Japan., Mori N; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Motz HM; Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama, Kanagawa 221-8686, Japan., Munakata K; Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621, Japan., Nakahira S; Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210, Japan., Nishimura J; Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210, Japan., Okuno S; Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama, Kanagawa 221-8686, Japan., Ormes JF; Department of Physics and Astronomy, University of Denver, Physics Building, Room 211, 2112 East Wesley Avenue, Denver, Colorado 80208-6900, USA., Ozawa S; Quantum ICT Advanced Development Center, National Institute of Information and Communications Technology, 4-2-1 Nukui-Kitamachi, Koganei, Tokyo 184-8795, Japan., Pacini L; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; Institute of Applied Physics (IFAC), National Research Council (CNR), Via Madonna del Piano, 10, 50019, Sesto Fiorentino, Italy., Papini P; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Rauch BF; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA., Ricciarini SB; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy.; Institute of Applied Physics (IFAC), National Research Council (CNR), Via Madonna del Piano, 10, 50019, Sesto Fiorentino, Italy., Sakai K; Center for Space Sciences and Technology, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250, USA.; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Center for Research and Exploration in Space Sciences and Technology, NASA/GSFC, Greenbelt, Maryland 20771, USA., Sakamoto T; College of Science and Engineering, Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo, Sagamihara, Kanagawa 252-5258, Japan., Sasaki M; Astroparticle Physics Laboratory, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Center for Research and Exploration in Space Sciences and Technology, NASA/GSFC, Greenbelt, Maryland 20771, USA.; Department of Astronomy, University of Maryland, College Park, Maryland 20742, USA., Shimizu Y; Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama, Kanagawa 221-8686, Japan., Shiomi A; College of Industrial Technology, Nihon University, 1-2-1 Izumi, Narashino, Chiba 275-8575, Japan., Spillantini P; Department of Physics, University of Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Stolzi F; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Sugita S; College of Science and Engineering, Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo, Sagamihara, Kanagawa 252-5258, Japan., Sulaj A; Department of Physical Sciences, Earth and Environment, University of Siena, via Roma 56, 53100 Siena, Italy.; INFN Sezione di Pisa, Polo Fibonacci, Largo B. Pontecorvo, 3-56127 Pisa, Italy., Takita M; Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8582, Japan., Tamura T; Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa, Yokohama, Kanagawa 221-8686, Japan., Terasawa T; Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba 277-8582, Japan., Torii S; Waseda Research Institute for Science and Engineering, Waseda University, 17 Kikuicho, Shinjuku, Tokyo 162-0044, Japan., Tsunesada Y; Graduate School of Science, Osaka Metropolitan University, Sugimoto, Sumiyoshi, Osaka 558-8585, Japan.; Nambu Yoichiro Institute for Theoretical and Experimental Physics, Osaka Metropolitan University, Sugimoto, Sumiyoshi, Osaka 558-8585, Japan., Uchihori Y; National Institutes for Quantum and Radiation Science and Technology, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan., Vannuccini E; INFN Sezione di Florence, Via Sansone, 1-50019, Sesto Fiorentino, Italy., Wefel JP; Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803, USA., Yamaoka K; Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan., Yanagita S; College of Science, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512, Japan., Yoshida A; College of Science and Engineering, Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo, Sagamihara, Kanagawa 252-5258, Japan., Yoshida K; Department of Electronic Information Systems, Shibaura Institute of Technology, 307 Fukasaku, Minuma, Saitama 337-8570, Japan., Zober WV; Department of Physics and McDonnell Center for the Space Sciences, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA.
Jazyk: angličtina
Zdroj: Physical review letters [Phys Rev Lett] 2023 Nov 10; Vol. 131 (19), pp. 191001.
DOI: 10.1103/PhysRevLett.131.191001
Abstrakt: Detailed measurements of the spectral structure of cosmic-ray electrons and positrons from 10.6 GeV to 7.5 TeV are presented from over 7 years of observations with the CALorimetric Electron Telescope (CALET) on the International Space Station. The instrument, consisting of a charge detector, an imaging calorimeter, and a total absorption calorimeter with a total depth of 30 radiation lengths at normal incidence and a fine shower imaging capability, is optimized to measure the all-electron spectrum well into the TeV region. Because of the excellent energy resolution (a few percent above 10 GeV) and the outstanding e/p separation (10^{5}), CALET provides optimal performance for a detailed search of structures in the energy spectrum. The analysis uses data up to the end of 2022, and the statistics of observed electron candidates has increased more than 3 times since the last publication in 2018. By adopting an updated boosted decision tree analysis, a sufficient proton rejection power up to 7.5 TeV is achieved, with a residual proton contamination less than 10%. The observed energy spectrum becomes gradually harder in the lower energy region from around 30 GeV, consistently with AMS-02, but from 300 to 600 GeV it is considerably softer than the spectra measured by DAMPE and Fermi-LAT. At high energies, the spectrum presents a sharp break around 1 TeV, with a spectral index change from -3.15 to -3.91, and a broken power law fitting the data in the energy range from 30 GeV to 4.8 TeV better than a single power law with 6.9 sigma significance, which is compatible with the DAMPE results. The break is consistent with the expected effects of radiation loss during the propagation from distant sources (except the highest energy bin). We have fitted the spectrum with a model consistent with the positron flux measured by AMS-02 below 1 TeV and interpreted the electron+positron spectrum with possible contributions from pulsars and nearby sources. Above 4.8 TeV, a possible contribution from known nearby supernova remnants, including Vela, is addressed by an event-by-event analysis providing a higher proton-rejection power than a purely statistical analysis.
Databáze: MEDLINE