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Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data

We present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend down to few GeV the spectra measured by H.E.S.S. and to infer t...

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Detalles Bibliográficos
Autores principales: Gaggero, Daniele, Grasso, Dario, Marinelli, Antonio, Taoso, Marco, Urbano, Alfredo, Ventura, Sofia
Lenguaje:eng
Publicado: SISSA 2017
Materias:
Acceso en línea:https://dx.doi.org/10.22323/1.301.0739
http://cds.cern.ch/record/2276768
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author Gaggero, Daniele
Grasso, Dario
Marinelli, Antonio
Taoso, Marco
Urbano, Alfredo
Ventura, Sofia
author_facet Gaggero, Daniele
Grasso, Dario
Marinelli, Antonio
Taoso, Marco
Urbano, Alfredo
Ventura, Sofia
author_sort Gaggero, Daniele
collection CERN
description We present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend down to few GeV the spectra measured by H.E.S.S. and to infer the primary CR radial distribution above 100 GeV. We compare those results with a CR transport model assuming a harder scaling of the diffusion coefficient with rigidity in the inner Galaxy. Such a behavior reproduces the radial dependence of the CR spectral index recently inferred from Fermi-LAT measurements in the inner GP. We find that, in this scenario, the bulk of the Galactic ridge emission can be naturally explained by the interaction of the diffuse, steady-state Galactic CR sea interacting with the gas present in the Central molecular zone. The evidence of a GC PeVatron is significantly weaker than that inferred adopting a conventional (softer) CR sea
id cern-2276768
institution Organización Europea para la Investigación Nuclear
language eng
publishDate 2017
publisher SISSA
record_format invenio
spelling cern-22767682023-03-14T19:24:49Zdoi:10.22323/1.301.0739http://cds.cern.ch/record/2276768engGaggero, DanieleGrasso, DarioMarinelli, AntonioTaoso, MarcoUrbano, AlfredoVentura, SofiaHard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray dataastro-ph.HEAstrophysics and AstronomyWe present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend down to few GeV the spectra measured by H.E.S.S. and to infer the primary CR radial distribution above 100 GeV. We compare those results with a CR transport model assuming a harder scaling of the diffusion coefficient with rigidity in the inner Galaxy. Such a behavior reproduces the radial dependence of the CR spectral index recently inferred from Fermi-LAT measurements in the inner GP. We find that, in this scenario, the bulk of the Galactic ridge emission can be naturally explained by the interaction of the diffuse, steady-state Galactic CR sea interacting with the gas present in the Central molecular zone. The evidence of a GC PeVatron is significantly weaker than that inferred adopting a conventional (softer) CR seaWe present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend down to few GeV the spectra measured by H.E.S.S. and to infer the primary CR radial distribution above 100 GeV.We compare those results with a CR transport model assuming a harder scaling of the diffusion coefficient with rigidity in the inner Galaxy. Such a behavior reproduces the radial dependence of the CR spectral index recently inferred from Fermi-LAT measurements in the inner GP. We find that, in this scenario, the bulk of the Galactic ridge emission can be naturally explained by the interaction of the diffuse, steady-state Galactic CR sea interacting with the gas present in the Central molecular zone. The evidence of a GC PeVatron is significantly weaker than that inferred adopting a conventional (softer) CR sea.We present a novel interpretation of the gamma-ray diffuse emission measured by H.E.S.S. in the Galactic Center (GC) region and the Galactic ridge. Our starting base is an updated analysis of PASS8 Fermi-LAT data, which allows to extend down to few GeV the spectra measured by H.E.S.S. and to infer the primary CR radial distribution above 100 GeV. We compare those results with a CR transport model assuming a harder scaling of the diffusion coefficient with rigidity in the inner Galaxy. Such a behavior reproduces the radial dependence of the CR spectral index recently inferred from Fermi-LAT measurements in the inner GP. We find that, in this scenario, the bulk of the Galactic ridge emission can be naturally explained by the interaction of the diffuse, steady-state Galactic CR sea interacting with the gas present in the Central molecular zone. The evidence of a GC PeVatron is significantly weaker than that inferred adopting a conventional (softer) CR sea.SISSAarXiv:1707.08473oai:cds.cern.ch:22767682017-07-26
spellingShingle astro-ph.HE
Astrophysics and Astronomy
Gaggero, Daniele
Grasso, Dario
Marinelli, Antonio
Taoso, Marco
Urbano, Alfredo
Ventura, Sofia
Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title_full Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title_fullStr Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title_full_unstemmed Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title_short Hard Cosmic Ray Sea in the Galactic Center: a consistent interpretation of H.E.S.S. and Fermi-LAT $\gamma$-ray data
title_sort hard cosmic ray sea in the galactic center: a consistent interpretation of h.e.s.s. and fermi-lat $\gamma$-ray data
topic astro-ph.HE
Astrophysics and Astronomy
url https://dx.doi.org/10.22323/1.301.0739
http://cds.cern.ch/record/2276768
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