The CALorimetric Electron Telescope (CALET) has been collecting data on the International Space Station for more than seven years since October 2015. CALET is an all-calorimetric instrument with a total vertical thickness of 30 radiation lengths and fine imaging capability, optimized for the measurement of the electron and positron (all-electron) spectrum well into the TeV energy region. The observed event statistics have increased more than three times since its last publication about the all-electron spectrum to 4.8 TeV in 2018. Based on Monte Carlo simulations, the data analysis effectively rejects background protons, resulting in less than 10% contamination up to the TeV region. The expected systematic errors are investigated. The significance of the cutoff at the TeV region in the energy spectrum, which is expected as a result of radiation loss during propagation, has increased to over 6 sigma. By observing the detailed structure in the TeV region of the energy spectrum, we will investigate on the presence of possible nearby cosmic-ray sources. In this paper, we will present the updated all-electron spectrum, and briefly discuss its interpretations.
The cosmic-ray electron and positron spectrum measured with CALET on the International Space Station / Akaike, Yosui; Adriani, Oscar; Asano, Katsuaki; Asaoka, Yoichi; Berti, Eugenio; Bigongiari, Gabriele; Binns, Walter Robert; Bongi, Massimo; Brogi, Paolo; Bruno, Alessandro; Cannady, Nicholas W; Castellini, Guido; Checchia, Caterina; Cherry, Walter Robert; Collazuol, Gianmaria; de Nolfo, Georgia A.; Ebisawa, Ken; Ficklin, Anthony W.; Fuke, Hideyuki; Gonzi, Sandro; Guzik, T. Gregory; Hams, Thomas; Hibino, Kinya; Ichimura, Masakatsu; Ioka, Kunihito; Ishizaki, Wataru; Israel, Martin H.; Kasahara, Katsumasa; Kataoka, Jun; Kataoka, Ryuho; Katayose, Yusaku; Kato, Chihiro; Kawanaka, Norita; Kawakubo, Yuta; Kobayashi, Kenko; Kohri, Kazunori; Krawczynski, Henric S.; Krizmanic, John F.; Maestro, Paolo; Marrocchesi, Pier Simone; Messineo, Alberto Maria; Mitchell, Jason W.; Miyake, Shoko; Moiseev, Alexander; Mori, Masaki; Mori, Nicola; Motz, Holger Martin; Munakata, Kazuoki; Nakahira, Satoshi; Nishimura, Jun; Okuno, Shoji; Ormes, Jonathan; Ozawa, Shunsuke; Pacini, Lorenzo; Papini, Paolo; Rauch, Brian Flint; Ricciarini, Sergio Bruno; Sakai, Kazuhiro; Sakamoto, Takanori; Sasaki, Makoto; Shimizu, Yuki; Shiomi, Atsushi; Spillantini, Piero; Stolzi, Francesco; Sugita, Satoshi; Sulaj, Arta; Takita, Masato; Tamura, Tadahisa; Terasawa, Toshio; Torii, Shoji; Tsunesada, Yoshiki; Uchihori, Yukio; Vannuccini, Elena; Wefel, John P.; Yamaoka, Kazutaka; Yanagita, Shohei; Yoshida, Atsumasa; Yoshida, Kenji; Zober, Wolfgang V;. - In: POS PROCEEDINGS OF SCIENCE. - ISSN 1824-8039. - ELETTRONICO. - 444 - 38th International Cosmic Ray Conference (ICRC2023):(2024), pp. 071.0-071.0. [10.22323/1.444.0071]
The cosmic-ray electron and positron spectrum measured with CALET on the International Space Station
Adriani, Oscar;Berti, Eugenio;Bongi, Massimo;Gonzi, Sandro;Spillantini, Piero;
2024
Abstract
The CALorimetric Electron Telescope (CALET) has been collecting data on the International Space Station for more than seven years since October 2015. CALET is an all-calorimetric instrument with a total vertical thickness of 30 radiation lengths and fine imaging capability, optimized for the measurement of the electron and positron (all-electron) spectrum well into the TeV energy region. The observed event statistics have increased more than three times since its last publication about the all-electron spectrum to 4.8 TeV in 2018. Based on Monte Carlo simulations, the data analysis effectively rejects background protons, resulting in less than 10% contamination up to the TeV region. The expected systematic errors are investigated. The significance of the cutoff at the TeV region in the energy spectrum, which is expected as a result of radiation loss during propagation, has increased to over 6 sigma. By observing the detailed structure in the TeV region of the energy spectrum, we will investigate on the presence of possible nearby cosmic-ray sources. In this paper, we will present the updated all-electron spectrum, and briefly discuss its interpretations.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.