OBSERVATION OF TeV GAMMA RAYS FROM THE UNIDENTIFIED SOURCE HESS J1841−055 WITH THE ARGO-YBJ EXPERIMENT
- Autori: Bartoli, B; Bernardini, P; Bi, XJ; Bolognino, I; Branchini, P; Budano, A; Calabrese Melcarne, AK; Camarri, P; Cao, Z; Cardarelli, R; Catalanotti, S; Cattaneo, C; Chen, SZ; Chen, TL; Chen, Y; Creti, P; Cui, SW; Dai, BZ; D’Ali Staiti, G; D’Amone, A; Danzengluobu; De Mitri, I; D’Ettorre Piazzoli, B; Di Girolamo, T; Ding, XH; Di Sciascio, G; Feng, CF; Feng, ZYa; Feng, ZYo; Galeazzi, F; Giroletti, E; Gou, QB; Guo, YQ; He, HH; Hu, HaB; Hu, HoB; Huang, Q; Iacovacci, M; Iuppa, R; James, I; Jia, HY; Labaciren; Li, HJ; Li, JY; Li, XX; Liguori, G; Liu, C; Liu, CQ; Liu, J; Liu, MY; Lu, H; Ma, LL; Ma, XH; Mancarella, G; Mari, SM; Marsella, G; Martello, D; Mastroianni, S; Montini, P; Ning, CC; Pagliaro, A; Panareo, M; Panico, B; Perrone, L; Pistilli, P; Ruggieri, F; Salvini, P; Santonico, R; Sbano, SN; Shen, PR; Sheng, XD; Shi, F; Surdo, A; Tan, YH; Vallania, P; Vernetto, S; Vigorito, C; Wang, B; Wang, H; Wu, CY; Wu, HR; Xu, B; Xue, L; Yang, QY; Yang, XC; Yao, ZG; Yuan, AF; Zha, M; Zhang, HM; Zhang, JLi; Zhang, JLo; Zhang, L; Zhang, P; Zhang, XY; Zhang, Y; Zhao, J; Zhaxiciren, Zhaxisangzhu; Zhou, XX; Zhu, FR; Zhu, QQ; Zizzi, G
- Anno di pubblicazione: 2013
- Tipologia: Articolo in rivista (Articolo in rivista)
- OA Link: http://hdl.handle.net/10447/76199
Abstract
We report the observation of a very high energy γ -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 2007 November to 2012 July. 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 σ = (0.40+0.32 )◦, which is consistent with −0.22 the HESS measurement. The observed energy spectrum is dN/dE = (9.0±1.6) × 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 γ-ray flux above 1 TeV is 1.3±0.4 Crab, 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.