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تسجيل مستخدم جديدObserving two dark accelerators around the Galactic Centre with Fermi Large Area Telescope
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We report the results from a detailed $gamma-$ray investigation in the field of two dark accelerators, HESS J1745-303 and HESS J1741-302, with $6.9$ years of data obtained by the Fermi Large Area Telescope. For HESS J1745-303, we found that its MeV-GeV emission is mainly originated from the Region A of the TeV feature. Its $gamma-$ray spectrum can be modeled with a single power-law with a photon index of $Gammasim2.5$ from few hundreds MeV to TeV. Moreover, an elongated feature, which extends from Region A toward northwest for $sim1.3^{circ}$, is discovered for the first time. The orientation of this feature is similar to that of a large scale atomic/molecular gas distribution. For HESS J1741-302, our analysis does not yield any MeV-GeV counterpart for this unidentified TeV source. On the other hand, we have detected a new point source, Fermi J1740.1-3013, serendipitously. Its spectrum is apparently curved which resembles that of a $gamma-$ray pulsar. This makes it possibly associated with PSR B1737-20 or PSR J1739-3023.
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