1 research outputs found
OBSERVATION OF TeV GAMMA RAYS FROM THE UNIDENTIFIED SOURCE HESS J1841ā055 WITH THE ARGO-YBJ EXPERIMENT
We report the observation of a very high energy Ī³ -ray source whose position is coincident with HESS J1841ā055.
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 Ļ = (0.40+0.32
ā0.22)ā¦, which is consistent with
the HESS measurement. The observed energy spectrum is dN/dE = (9.0 Ā± 1.6) Ć 10ā13(E/5 TeV)ā2.32Ā±0.23
photons cmā2 sā1 TeVā1, in the energy range 0.9ā50 TeV. The integral Ī³ -ray flux above 1 TeV is 1.3 Ā± 0.4 Crab,
which is 3.2 Ā± 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