Dr Andrea Caliandro
HESS J1745-303 is an extended, unidentified VHE (very high energy) gamma-ray source located at the edge of the giant molecular ring surrounding the Galactic Center. Unraveling the nature of this emission is not easy in this region densely populated by plausible VHE emission candidates, like supernova remnants, pulsar wind nebulae, and X-ray binaries. Recently, an excess positionally consistent with the HESS source has been observed in the GeV energy range with the Fermi-LAT data. A detailed and more specific analysis performed with the most updated knowledge of the Fermi-LAT instrument response, and as well of the gamma-ray sky model, leads to the discovery of important features that can strongly help in the understanding of this source. The interpretation of the GeV/TeV connection is discussed, especially in the context of supernova remnant interacting with molecular clouds.