Publication:
Discovery of the Ultrahigh-energy Gamma-Ray Source LHAASO J2108+5157

Issued Date

2021-10-01

Resource Type

Article

ISSN

20418213
20418205

DOI

10.3847/2041-8213/ac2579

Other identifier(s)

2-s2.0-85116440330

Rights

Mahidol University

Rights Holder(s)

SCOPUS

Bibliographic Citation

Astrophysical Journal Letters. Vol.919, No.2 (2021)

Suggested Citation

Zhen Cao, F. Aharonian, Q. An, Axikegu, L. X. Bai, Y. X. Bai, Y. W. Bao, D. Bastieri, X. J. Bi, Y. J. Bi, H. Cai, J. T. Cai, Zhe Cao, J. Chang, J. F. Chang, B. M. Chen, E. S. Chen, J. Chen, Liang Chen, Long Chen, M. J. Chen, M. L. Chen, Q. H. Chen, S. H. Chen, S. Z. Chen, T. L. Chen, X. L. Chen, Y. Chen, N. Cheng, Y. D. Cheng, S. W. Cui, X. H. Cui, Y. D. Cui, B. D'Ettorre Piazzoli, B. Z. Dai, H. L. Dai, Z. G. Dai, Dan Zeng Dan-Zeng-Luo-Bu, D. Della Volpe, X. J. Dong, K. K. Duan, J. H. Fan, Y. Z. Fan, Z. X. Fan, J. Fang, K. Fang, C. F. Feng, L. Feng, S. H. Feng, Y. L. Feng, B. Gao, C. D. Gao, L. Q. Gao, Q. Gao, W. Gao, M. M. Ge, L. S. Geng, G. H. Gong, Q. B. Gou, M. H. Gu, F. L. Guo, J. G. Guo, X. L. Guo, Y. Q. Guo, Y. Y. Guo, Y. A. Han, H. H. He, H. N. He, J. C. He, S. L. He, X. B. He, Y. He, M. Heller, Y. K. Hor, C. Hou, H. B. Hu, S. Hu, S. C. Hu, X. J. Hu, D. H. Huang, Q. L. Huang, W. H. Huang, X. T. Huang, X. Y. Huang, Z. C. Huang, F. Ji, X. L. Ji, H. Y. Jia, K. Jiang, Z. J. Jiang, C. Jin, T. Ke, D. Kuleshov, K. Levochkin, B. B. Li, Cheng Li, Cong Li, F. Li, H. B. Li, H. C. Li Discovery of the Ultrahigh-energy Gamma-Ray Source LHAASO J2108+5157. Astrophysical Journal Letters. Vol.919, No.2 (2021). doi:10.3847/2041-8213/ac2579 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/76847

Research Projects

Organizational Units

Authors

Journal Issue

Thesis

Title

Discovery of the Ultrahigh-energy Gamma-Ray Source LHAASO J2108+5157

Author(s)

Zhen Cao
 F. Aharonian
 Q. An
 Axikegu
 L. X. Bai
 Y. X. Bai
 Y. W. Bao
 D. Bastieri
 X. J. Bi
 Y. J. Bi
 H. Cai
 J. T. Cai
 Zhe Cao
 J. Chang
 J. F. Chang
 B. M. Chen
 E. S. Chen
 J. Chen
 Liang Chen
 Long Chen
 M. J. Chen
 M. L. Chen
 Q. H. Chen
 S. H. Chen
 S. Z. Chen
 T. L. Chen
 X. L. Chen
 Y. Chen
 N. Cheng
 Y. D. Cheng
 S. W. Cui
 X. H. Cui
 Y. D. Cui
 B. D'Ettorre Piazzoli
 B. Z. Dai
 H. L. Dai
 Z. G. Dai
 Dan Zeng Dan-Zeng-Luo-Bu
 D. Della Volpe
 X. J. Dong
 K. K. Duan
 J. H. Fan
 Y. Z. Fan
 Z. X. Fan
 J. Fang
 K. Fang
 C. F. Feng
 L. Feng
 S. H. Feng
 Y. L. Feng
 B. Gao
 C. D. Gao
 L. Q. Gao
 Q. Gao
 W. Gao
 M. M. Ge
 L. S. Geng
 G. H. Gong
 Q. B. Gou
 M. H. Gu
 F. L. Guo
 J. G. Guo
 X. L. Guo
 Y. Q. Guo
 Y. Y. Guo
 Y. A. Han
 H. H. He
 H. N. He
 J. C. He
 S. L. He
 X. B. He
 Y. He
 M. Heller
 Y. K. Hor
 C. Hou
 H. B. Hu
 S. Hu
 S. C. Hu
 X. J. Hu
 D. H. Huang
 Q. L. Huang
 W. H. Huang
 X. T. Huang
 X. Y. Huang
 Z. C. Huang
 F. Ji
 X. L. Ji
 H. Y. Jia
 K. Jiang
 Z. J. Jiang
 C. Jin
 T. Ke
 D. Kuleshov
 K. Levochkin
 B. B. Li
 Cheng Li
 Cong Li
 F. Li
 H. B. Li
 H. C. Li

Other Contributor(s)

State Key Laboratory of Particle Detection & Electronics
 Nanjing University
 Shanghai Astronomical Observatory Chinese Academy of Sciences
 Institute for Nuclear Research of the Russian 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
 Dublin Institute for Advanced Studies
 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

Abstract

We report the discovery of an ultrahigh-energy (UHE) gamma-ray source, LHAASO J2108+5157, by analyzing the LHAASO-KM2A data of 308.33 live days. A significant excess of gamma ray-induced showers is observed in both energy bands of 25-100 and >100 TeV with 9.5σ and 8.5σ, respectively. This source is not significantly favored as an extended source with an angular extension smaller than the point-spread function of KM2A. The measured energy spectrum from 20 to 200 TeV can be approximately described by a power-law function with an index of-2.83 ± 0.18stat. A harder spectrum is demanded at lower energies considering the flux upper limit set by Fermi-LAT observations. The position of the gamma-ray emission is correlated with a giant molecular cloud, which favors a hadronic origin. No obvious counterparts have been found, and deeper multiwavelength observations will help to cast new light on this intriguing UHE source.

Keyword(s)

Earth and Planetary Sciences
 Physics and Astronomy

Availability

URI

https://repository.li.mahidol.ac.th/handle/123456789/76847

Collections

Scopus 2021