ICRC2015

Session

Parallel GA05 GeV excess GalCen

31 Jul 2015, 11:00

World Forum

431. Interacting Cosmic Rays with Molecular Clouds in the Galactic Center

Chris Gordon (University of Canterbury)

31/07/2015, 11:00

GA-TH

Oral contribution

The High-Energy Stereoscopic System (HESS) has detected diffuse TeV emission correlated with the distribution of molecular gas along the Ridge at the Galactic Center. Diffuse, nonthermal emission is also seen by the Fermi large area telescope (Fermi-LAT) in the GeV range and by radio telescopes in the GHz range. Additionally, there is a distinct, spherically symmetric excess of gamma rays...

801. Observations of High-Energy Gamma-Ray Emission Toward the Galactic Centre

Dr Troy Porter (Stanford University)

31/07/2015, 11:15

GA-EX

Oral contribution

The inner region of the Milky Way is one of the most interesting and complex regions of the gamma-ray sky. The intense interstellar emission and resolved point sources, as well as potential contributions by other sources such as unresolved source populations and dark matter, complicate the interpretation of the data. In this talk, we report on the Fermi-LAT team analysis of a 15x15 degree...

1140. Unveiling the nature of the “Fermi GeV excess”: robust characterisation and possible interpretations

Francesca Calore (University of Amsterdam)

31/07/2015, 11:30

GA-TH

Oral contribution

Recently, a spatially extended excess of gamma rays collected by the *Fermi*-LAT from the inner region of the Milky Way has been claimed by different and independent groups. I will present a robust characterisation of the morphology and spectral properties of such an extended diffuse emission, including systematic uncertainties that are related to the high density of cosmic rays, gas, magnetic...

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

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

31/07/2015, 11:45

GA-TH

Oral contribution

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...

1234. Testing the interpretation of the Fermi Galactic center excess in terms of unresolved point sources

Christoph Weniger (University of Amsterdam)

31/07/2015, 12:00

GA-TH

Oral contribution

We present a new, powerful and background-independent technique to constrain the luminosity function of point source populations that might contribute to the observed GeV excess emission around the Galactic center. Using this technique, we search for indications of such a population in the latest Fermi LAT data and discuss, for the case of milli-second pulsars, the implications for...

1361. Search for gamma-ray line signatures with H.E.S.S.

Matthieu Kieffer (LPNHE, Paris)

31/07/2015, 12:15

DM-EX

Oral contribution

Most of results from astrophysical observations point to a 27% contribution of non-baryonic dark matter to the mass-energy budget of the universe. Although still undetermined, strongly motivated candidates in form of weakly interactive massive particles could explain its nature and their annihilations or decays would give rise to detectable signatures in gamma rays. In 2012, the H.E.S.S....