July 29, 2015 to August 6, 2015
World Forum
Europe/Amsterdam timezone

Interpreting the GeV gamma-ray excess in terms of non-standard cosmic-ray diffusion models.

Jul 31, 2015, 11:45 AM
Yangtze 1 (World Forum)

Yangtze 1

World Forum

Churchillplein 10 2517 JW Den Haag The Netherlands
Oral contribution GA-TH Parallel GA05 GeV excess GalCen


Dr Alfredo Urbano (SISSA - International School for Advanced Studies)


A GeV gamma-ray excess has possibly been individuated in Fermi-LAT data from the Galactic Center, and interpreted in terms of Dark Matter annihilations, either in hadronic or leptonic channels. However, the identification of such an excess strongly relies on the capability of carefully assessing the background over which the excess is supposed to emerge. For this reason, it is crucial to critically scrutinise the role of the diffuse gamma-ray background as well as the presence of additional astrophysical emissions. Here, making use of advanced numerical tools, we conduct such analysis focusing our attention on two crucial astrophysical ingredients that may significantly alter the diffuse gamma-ray background from the innermost region of the Milky Way galaxy. On the one hand, motivated by simple arguments related to the motion of electrons along ordered magnetic field lines, we allow for anisotropic cosmic-ray diffusion. On the other one, motivated by the possibility to have a population of supernovae in the region of the Galactic bulge, we explore non-standard cosmic-ray source terms. We critically discuss how the inclusion of these two ingredients strongly affects the interpretation of the GeV gamma-ray excess in terms of Dark Matter annihilation.
Collaboration -- not specified --
Registration number following "ICRC2015-I/" 515

Primary author

Dr Alfredo Urbano (SISSA - International School for Advanced Studies)


Daniele Gaggero Marco Taoso Mr Mauro Valli (SISSA - International School for Advanced Studies) Piero Ullio (SISSA)

Presentation materials