A spherical-symmetric gamma-ray emission from the inner region of the Galaxy (at least up to roughly 100 in latitude and longitude) has been recently identified in FermiLAT data, and initially associated to dark matter particle annihilations. Guided by the evidence for a high gas density in the inner kpc of the Galaxy correlated with a very large Supernova rate, and hence with ongoing cosmic-ray acceleration, we investigate instead the possibility of addressing this excess in terms of ordinary cosmic-ray sources and standard steady-state diffusion. We alter the source term, and consistently the correlated gamma-ray emissions, in the context of a template-fitting analysis. We focus on a region of interest (ROT) defined as: vertical bar l vertical bar < 20 degrees; 2 degrees < vertical bar b vertical bar < 20 degrees, with l and b the Galactic longitude and latitude coordinates. We analyze in detail the overall goodness of the fit of our framework, and perform a detailed direct comparison against data examining profiles in different directions. Remarkably, the test statistic of the fit related to our scenario turns out to be as good as the Dark Matter one in the ROT here considered.
|Titolo:||Towards a realistic astrophysical interpretation of the gamma-ray Galactic center excess|
|Autori:||Gaggero, D.; Taoso, M.; Urbano, A.; Valli, M.; Ullio, P.|
|Rivista:||JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS|
|Data di pubblicazione:||2015|
|Digital Object Identifier (DOI):||10.1088/1475-7516/2015/12/056|
|Appare nelle tipologie:||1.1 Journal article|