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dc.contributor.authorPIVATO, G.
dc.contributor.authorW. HEWITT, J.
dc.contributor.authorTIBALDO, L.
hal.structure.identifierLaboratoire Univers et Particules de Montpellier [LUPM]
dc.contributor.authorACERO, Fabio
hal.structure.identifierAstrophysique Interprétation Modélisation [AIM (UMR7158 / UMR_E_9005 / UM_112)]
dc.contributor.authorBALLET, Jean
hal.structure.identifierInstitut de recherche en astrophysique et planétologie [IRAP]
dc.contributor.authorJ. BRANDT, T.
dc.contributor.authorDE PALMA, F.
dc.contributor.authorGIORDANO, F.
dc.contributor.authorH. JANSSEN, G.
dc.contributor.authorJÓHANNESSON, G.
hal.structure.identifierAstroparticules [ASTRO]
dc.contributor.authorSMITH, David Stanley
dc.date.issued2013
dc.identifier.issn0004-637X
dc.description.abstractEnWe present the analysis of Fermi Large Area Telescope γ-ray observations of HB 21 (G89.0+4.7). We detect significant γ-ray emission associated with the remnant: the flux >100 MeV is 9.4 ± 0.8 (stat) ± 1.6 (syst) × 10-11 erg cm-2 s-1. HB 21 is well modeled by a uniform disk centered at l = 88fdg75 ± 0fdg04, b = +4fdg65 ± 0fdg06 with a radius of 1fdg19 ± 0fdg06. The γ-ray spectrum shows clear evidence of curvature, suggesting a cutoff or break in the underlying particle population at an energy of a few GeV. We complement γ-ray observations with the analysis of the WMAP 7 yr data from 23 to 93 GHz, achieving the first detection of HB 21 at these frequencies. In combination with archival radio data, the radio spectrum shows a spectral break, which helps to constrain the relativistic electron spectrum, and, in turn, parameters of simple non-thermal radiation models. In one-zone models multiwavelength data favor the origin of γ rays from nucleon-nucleon collisions. A single population of electrons cannot produce both γ rays through bremsstrahlung and radio emission through synchrotron radiation. A predominantly inverse-Compton origin of the γ-ray emission is disfavored because it requires lower interstellar densities than are inferred for HB 21. In the hadronic-dominated scenarios, accelerated nuclei contribute a total energy of ~3 × 1049 erg, while, in a two-zone bremsstrahlung-dominated scenario, the total energy in accelerated particles is ~1 × 1049 erg.
dc.language.isoen
dc.publisherAmerican Astronomical Society
dc.subject.enacceleration of particles
dc.subject.encosmic rays
dc.subject.enISM: individual objects (HB 21)
dc.subject.enradiation mechanisms: non-thermal
dc.title.enFERMI LAT AND WMAP OBSERVATIONS OF THE SUPERNOVA REMNANT HB 21
dc.typeArticle de revue
dc.identifier.doi10.1088/0004-637X/779/2/179
dc.subject.halPhysique [physics]/Astrophysique [astro-ph]/Phénomènes cosmiques de haute energie [astro-ph.HE]
dc.subject.halPlanète et Univers [physics]/Astrophysique [astro-ph]/Phénomènes cosmiques de haute energie [astro-ph.HE]
dc.identifier.arxiv1311.0393
bordeaux.journalThe Astrophysical Journal
bordeaux.page2
bordeaux.volume779
bordeaux.peerReviewedoui
hal.identifierin2p3-00935224
hal.version1
hal.popularnon
hal.audienceNon spécifiée
hal.origin.linkhttps://hal.archives-ouvertes.fr//in2p3-00935224v1
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