Observation of TeV gamma-rays from the unidentified source HESS
  J1841-055 with the ARGO-YBJ experiment

Bartoli, B.; Bernardini, P.; Bi, X. J.; Bolognino, I.; Branchini, P.; Budano, A.; Camarri, P.; Cao, Z.; Cardarelli, R.; Catalanotti, S.; Cattaneo, C.; Chen, S. Z.; Chen, T. L.; Chen, Y.; Collaboration, The ARGO-YBJ; Creti, P.; Cui, S. W.; Dai, B. Z.; DAmone, A.; Danzengluobu; De Mitri, I.; Di Girolamo, T.; Di Sciascio, G.; Ding, X. H.; Feng, C. F.; Feng, Zhaoyang; Feng, Zhenyong; Galeazzi, F.; Giroletti, E.; Gou, Q. B.; Guo, Y. Q.; He, H. H.; Hu, Haibing; Hu, Hongbo; Huang, Q.; Iacovacci, M.; Iuppa, R.; James, I.; Jia, H. Y.; Labaciren; Li, H. J.; Li, J. Y.; Li, X. X.; Liguori, G.; Liu, C.; Liu, C. Q.; Liu, J.; Liu, M. Y.; Lu, H.; Ma, L. L.; Ma, X. H.; Mancarella, G.; Mari, S. M.; Marsella, G.; Martello, D.; Mastroianni, S.; Melcarne, A. K. Calabrese; Montini, P.; Ning, C. C.; Pagliaro, A.; Panareo, M.; Panico, B.; Perrone, L.; Piazzoli, B. DEttorre; Pistilli, P.; Ruggieri, F.; Salvini, P.; Santonico, R.; Sbano, S. N.; Shen, P. R.; Sheng, X. D.; Shi, F.; Staiti, G. DAli; Surdo, A.; Tan, Y. H.; Vallania, P.; Vernetto, S.; Vigorito, C.; Wang, B.; Wang, H.; Wu, C. Y.; Wu, H. R.; Xu, B.; Xue, L.; Yang, Q. Y.; Yang, X. C.; Yao, Z. G.; Yuan, A. F.; Zha, M.; Zhang, H. M.; Zhang, Jianli; Zhang, Jilong; Zhang, L.; Zhang, P.; Zhang, X. Y.; Zhang, Y.; Zhao, J.; Zhaxiciren; Zhaxisangzhu; Zhou, X. X.; Zhu, F. R.; Zhu, Q. Q.; Zizzi, G.

research

Observation of TeV gamma-rays from the unidentified source HESS J1841-055 with the ARGO-YBJ experiment

Authors: B. Bartoli
P. Bernardini
X. J. Bi
I. Bolognino
P. Branchini
A. Budano
P. Camarri
Z. Cao
R. Cardarelli
S. Catalanotti
C. Cattaneo
S. Z. Chen
T. L. Chen
Y. Chen
The ARGO-YBJ Collaboration
P. Creti
S. W. Cui
B. Z. Dai
A. DAmone
Danzengluobu
I. De Mitri
T. Di Girolamo
G. Di Sciascio
X. H. Ding
C. F. Feng
Zhaoyang Feng
Zhenyong Feng
F. Galeazzi
E. Giroletti
Q. B. Gou
Y. Q. Guo
H. H. He
Haibing Hu
Hongbo Hu
Q. Huang
M. Iacovacci
R. Iuppa
I. James
H. Y. Jia
Labaciren
H. J. Li
J. Y. Li
X. X. Li
G. Liguori
C. Liu
C. Q. Liu
J. Liu
M. Y. Liu
H. Lu
L. L. Ma
X. H. Ma
G. Mancarella
S. M. Mari
G. Marsella
D. Martello
S. Mastroianni
A. K. Calabrese Melcarne
P. Montini
C. C. Ning
A. Pagliaro
M. Panareo
B. Panico
L. Perrone
B. DEttorre Piazzoli
P. Pistilli
F. Ruggieri
P. Salvini
R. Santonico
S. N. Sbano
P. R. Shen
X. D. Sheng
F. Shi
G. DAli Staiti
A. Surdo
Y. H. Tan
P. Vallania
S. Vernetto
C. Vigorito
B. Wang
H. Wang
C. Y. Wu
H. R. Wu
B. Xu
L. Xue
Q. Y. Yang
X. C. Yang
Z. G. Yao
A. F. Yuan
M. Zha
H. M. Zhang
Jianli Zhang
Jilong Zhang
L. Zhang
P. Zhang
X. Y. Zhang
Y. Zhang
J. Zhao
Zhaxiciren
Zhaxisangzhu
X. X. Zhou
F. R. Zhu
Q. Q. Zhu
G. Zizzi
Publication date: 1 January 2013
Publisher: 'IOP Publishing'
Doi

Abstract

We report the observation of a very high energy \gamma-ray source, whose position is coincident with HESS J1841-055. This source has been observed for 4.5 years by the ARGO-YBJ experiment from November 2007 to July 2012. Its emission is detected with a statistical significance of 5.3 standard deviations. Parameterizing the source shape with a two-dimensional Gaussian function we estimate an extension \sigma=(0.40(+0.32,-0.22}) degree, consistent with the HESS measurement. The observed energy spectrum is dN/dE =(9.0-+1.6) x 10^{-13}(E/5 TeV)^{-2.32-+0.23} photons cm^{-2} s^{-1} TeV^{-1}, in the energy range 0.9-50 TeV. The integral \gamma-ray flux above 1 TeV is 1.3-+0.4 Crab units, which is 3.2-+1.0 times the flux derived by HESS. The differences in the flux determination between HESS and ARGO-YBJ, and possible counterparts at other wavelengths are discussed.Comment: 17 pages, 4 figures, have been accepted for publication in Ap