Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

doi:10.1103/PhysRevLett.132.131002

	Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A
	Cao, Zhen 5,27,28; Aharonian, F.6,7; Axikegu 8; Bai, Y. X.5,27; Bao, Y. W.9; Bastieri, D.10; Bi, X. J.5,27,28; Bi, Y. J.5,27; Bian, W.11; Bukevich, A. V.12
刊名	Physical Review Letters
	2024-03-29
卷号	132 期号:13
关键词	Research Areas Cosmic ray composition & spectra Gravitation, Cosmology & Astrophysics
ISSN号	0031-9007
DOI	10.1103/PhysRevLett.132.131002
产权排序	第25完成单位
文献子类	Journal article (JA)
英文摘要	We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components. © 2024 American Physical Society.
学科主题	天文学
URL标识	查看原文
资助项目	N/A
语种	英语
资助机构	N/A
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/26755]
专题	星系类星体研究组
作者单位	1.National Space Science Center, Chinese Academy of Sciences, Beijing, 100190, China; 2.School of Physics, Huazhong University of Science and Technology, Hubei, Wuhan, 430074, China 3.Center for Relativistic Astrophysics and High Energy Physics, School of Physics and Materials Science, Institute of Space Science and Technology, Nanchang University, Jiangxi, Nanchang, 330031, China; 4.Moscow Institute of Physics and Technology, Moscow, 141700, Russia; 5.Tianfu Cosmic Ray Research Center, Sichuan, Chengdu, 610000, China; 6.Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin, Ireland; 7.Max-Planck-Institut for Nuclear Physics, P.O. Box 103980, Heidelberg, 69029, Germany; 8.School of Physical Science and Technology, School of Information Science and Technology, Southwest Jiaotong University, Sichuan, Chengdu, 610031, China; 9.School of Astronomy and Space Science, Nanjing University, Jiangsu, Nanjing, 210023, China; 10.Center for Astrophysics, Guangzhou University, Guangdong, Guangzhou, 510006, China;
推荐引用方式 GB/T 7714	Cao, Zhen,Aharonian, F.,Axikegu,et al. Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A[J]. Physical Review Letters,2024,132(13).
APA	Cao, Zhen.,Aharonian, F..,Axikegu.,Bai, Y. X..,Bao, Y. W..,...&Takata, J..(2024).Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A.Physical Review Letters,132(13).
MLA	Cao, Zhen,et al."Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A".Physical Review Letters 132.13(2024).