Observation of large-scale anisotropy in the arrival directions of cosmic rays with LHAASO-KM2A
Issued Date
2022-03-18
Resource Type
eISSN
18248039
Scopus ID
2-s2.0-85145006465
Journal Title
Proceedings of Science
Volume
395
Rights Holder(s)
SCOPUS
Bibliographic Citation
Proceedings of Science Vol.395 (2022)
Suggested Citation
Gao W. Observation of large-scale anisotropy in the arrival directions of cosmic rays with LHAASO-KM2A. Proceedings of Science Vol.395 (2022). Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/86561
Title
Observation of large-scale anisotropy in the arrival directions of cosmic rays with LHAASO-KM2A
Author(s)
Author's Affiliation
State Key Laboratory of Particle Detection & Electronics
Nanjing University
Shanghai Astronomical Observatory Chinese Academy of Sciences
Shandong University
Wuhan University
Yunnan University
Institute of High Energy Physics Chinese Academy of Science
University of Chinese Academy of Sciences
Guangzhou University
Tsinghua University
Sun Yat-Sen University
University of Science and Technology of China
Zhengzhou University
Institiúid Ard-Lénn Bhaile Átha Cliath
Università degli Studi di Napoli Federico II
Sichuan University
National Astronomical Observatories Chinese Academy of Sciences
Max-Planck-Institut für Kernphysik
Southwest Jiaotong University
Purple Mountain Observatory Chinese Academy of Sciences
Université de Genève
Hebei Normal University
Tibet University
TIANFU Cosmic Ray Research Center
Nanjing University
Shanghai Astronomical Observatory Chinese Academy of Sciences
Shandong University
Wuhan University
Yunnan University
Institute of High Energy Physics Chinese Academy of Science
University of Chinese Academy of Sciences
Guangzhou University
Tsinghua University
Sun Yat-Sen University
University of Science and Technology of China
Zhengzhou University
Institiúid Ard-Lénn Bhaile Átha Cliath
Università degli Studi di Napoli Federico II
Sichuan University
National Astronomical Observatories Chinese Academy of Sciences
Max-Planck-Institut für Kernphysik
Southwest Jiaotong University
Purple Mountain Observatory Chinese Academy of Sciences
Université de Genève
Hebei Normal University
Tibet University
TIANFU Cosmic Ray Research Center
Other Contributor(s)
Abstract
A global large-scale anisotropy in the arrival directions of cosmic rays were observed both in the Northern and Southern Hemisphere. It is evident that the morphology of the large-scale anisotropy and magnitude is energy dependent. However, only a few experiments can up to PeV with long term data accumulation. The measurement of anisotropy at high energies can provide more clues to the origin and propagation of cosmic rays. The Large High Altitude Air Shower Observatory (LHAASO), covering an area of 1.36 square kilometer, detect cosmic rays from sub-TeV up to 100 PeV with good element discrimination ability. In this paper, data collected by half array of KM2A during 2020 is used to analyze the anisotropy. The anisoptropies from 23 TeV up to 985 TeV are reported. The "inverse" anisotropy is observed at 985 TeV with significance of 5σ. The evolution of the anisotropy with energy is consistent with the others. With the operation of LHAASO, more accurate observation for the cosmic-ray anisotropy at higher energy will be made.