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Title: The GeV Excess Shining Through: Background Systematics for the Inner Galaxy Analysis

Recently, a spatially extended excess of gamma rays collected by the Fermi-LAT from the inner region of the Milky Way has been detected by different groups and with increasingly sophisticated techniques. Yet, any final conclusion about the morphology and spectral properties of such an extended diffuse emission are subject to a number of potentially critical uncertainties, related to the high density of cosmic rays, gas, magnetic fields and abundance of point sources. We will present a thorough study of the systematic uncertainties related to the modelling of diffuse background and to the propagation of cosmic rays in the inner part of our Galaxy. We will test a large set of models for the Galactic diffuse emission, generated by varying the propagation parameters within extreme conditions. By using those models in the fit of Fermi-LAT data as Galactic foreground, we will show that the gamma-ray excess survives and we will quantify the uncertainties on the excess emission morphology and energy spectrum.
Authors:
; ;
Publication Date:
OSTI Identifier:
1223210
Report Number(s):
FERMILAB-CONF--15-037-A
arXiv eprint number arXiv:1502.02805; TRN: US1601471
DOE Contract Number:
AC02-07CH11359
Resource Type:
Conference
Resource Relation:
Conference: Fifth International Fermi Symposium, Nagoya (Japan), 20-24 Oct 2014
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; MILKY WAY; COSMIC RADIATION; GAMMA RADIATION; GEV RANGE; ENERGY SPECTRA; DENSITY; MORPHOLOGY; SIMULATION; COSMIC PHOTONS; PHOTON TRANSPORT; MATHEMATICAL MODELS; DATA COVARIANCES