能量超过10²⁰ 电子伏特的宇宙射线的各向同性支持其重质量组成。

Isotropy of Cosmic Rays beyond 10^{20} eV Favors Their Heavy Mass Composition.

作者信息

Abbasi R U, Abe Y, Abu-Zayyad T, Allen M, Arai Y, Arimura R, Barcikowski E, Belz J W, Bergman D R, Blake S A, Buckland I, Cheon B G, Chikawa M, Fujii T, Fujisue K, Fujita K, Fujiwara R, Fukushima M, Furlich G, Globus N, Gonzalez R, Hanlon W, Hayashida N, He H, Hibi R, Hibino K, Higuchi R, Honda K, Ikeda D, Inoue N, Ishii T, Ito H, Ivanov D, Iwasaki A, Jeong H M, Jeong S, Jui C C H, Kadota K, Kakimoto F, Kalashev O, Kasahara K, Kasami S, Kawakami S, Kawata K, Kharuk I, Kido E, Kim H B, Kim J H, Kim J H, Kim S W, Kimura Y, Komae I, Kuzmin V, Kuznetsov M, Kwon Y J, Lee K H, Lubsandorzhiev B, Lundquist J P, Matsumiya H, Matsuyama T, Matthews J N, Mayta R, Mizuno K, Murakami M, Myers I, Lee K H, Nagataki S, Nakai K, Nakamura T, Nishio E, Nonaka T, Oda H, Ogio S, Onishi M, Ohoka H, Okazaki N, Oku Y, Okuda T, Omura Y, Ono M, Oshima A, Oshima H, Ozawa S, Park I H, Park K Y, Potts M, Pshirkov M S, Remington J, Rodriguez D C, Rott C, Rubtsov G I, Ryu D, Sagawa H, Saito R, Sakaki N, Sako T, Sakurai N, Sato D, Sato K, Sato S, Sekino K, Shah P D, Shibata N, Shibata T, Shikita J, Shimodaira H, Shin B K, Shin H S, Shinto D, Smith J D, Sokolsky P, Stokes B T, Stroman T A, Takagi Y, Takahashi K, Takamura M, Takeda M, Takeishi R, Taketa A, Takita M, Tameda Y, Tanaka K, Tanaka M, Tanoue Y, Thomas S B, Thomson G B, Tinyakov P, Tkachev I, Tokuno H, Tomida T, Troitsky S, Tsuda R, Tsunesada Y, Udo S, Urban F, Warren D, Wong T, Yamazaki K, Yashiro K, Yoshida F, Zhezher Y, Zundel Z

机构信息

Department of Physics, Loyola University Chicago, Chicago, Illinois 60660, USA.

Academic Assembly School of Science and Technology Institute of Engineering, Shinshu University, Nagano, Nagano 380-8554, Japan.

出版信息

Phys Rev Lett. 2024 Jul 26;133(4):041001. doi: 10.1103/PhysRevLett.133.041001.

DOI:10.1103/PhysRevLett.133.041001

PMID:39121414

Abstract

We report an estimation of the injected mass composition of ultrahigh energy cosmic rays (UHECRs) at energies higher than 10 EeV. The composition is inferred from an energy-dependent sky distribution of UHECR events observed by the Telescope Array surface detector by comparing it to the Large Scale Structure of the local Universe. In the case of negligible extragalactic magnetic fields (EGMFs), the results are consistent with a relatively heavy injected composition at E∼10 EeV that becomes lighter up to E∼100 EeV, while the composition at E>100 EeV is very heavy. The latter is true even in the presence of highest experimentally allowed extragalactic magnetic fields, while the composition at lower energies can be light if a strong EGMF is present. The effect of the uncertainty in the galactic magnetic field on these results is subdominant.

摘要

我们报告了对能量高于10 EeV的超高能宇宙射线（UHECRs）注入质量组成的估计。通过将望远镜阵列表面探测器观测到的UHECR事件的能量依赖天空分布与本地宇宙的大尺度结构进行比较，推断出其组成。在星系际磁场（EGMFs）可忽略不计的情况下，结果与E∼10 EeV时相对较重的注入组成一致，在E∼100 EeV时变得较轻，而E>100 EeV时的组成非常重。即使存在实验允许的最强星系际磁场，后者也是如此，而如果存在强EGMF，较低能量时的组成可能较轻。银河磁场不确定性对这些结果的影响是次要的。