Afficher la notice abrégée

WEBT and XMM-Newton observations of 3C 454.3 during the post-outburst phase. Detection of the little and big blue bumps

hal.structure.identifierINAF - Osservatorio Astrofisico di Torino [OATo]
dc.contributor.authorRAITERI, C. M.
hal.structure.identifierINAF - Osservatorio Astrofisico di Torino [OATo]
dc.contributor.authorVILLATA, M.
dc.contributor.authorLARIONOV, V. M.
dc.contributor.authorPURSIMO, T.
dc.contributor.authorIBRAHIMOV, M. A.
dc.contributor.authorNILSSON, K.
hal.structure.identifierLaboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux [L3AB]
hal.structure.identifierLaboratoire d'Astrophysique de Bordeaux [Pessac] [LAB]
hal.structure.identifierObservatoire aquitain des sciences de l'univers [OASU]
dc.contributor.authorCHARLOT, P.
dc.date.created2007-08-21
dc.date.issued2007
dc.identifier.issn0004-6361
dc.description.abstractEnThe blazar 3C 454.3 underwent an unprecedented optical outburst in spring 2005. This was first followed by a mm and then by a cm radio outburst, which peaked in February 2006. We report on follow-up observations by the WEBT to study the multiwavelength emission in the post-outburst phase. XMM-Newton observations on July and December 2006 added information on the X-ray and UV fluxes. The source was in a faint state. The radio flux at the higher frequencies showed a fast decreasing trend, which represents the tail of the big radio outburst. It was followed by a quiescent state, common at all radio frequencies. In contrast, moderate activity characterized the NIR and optical light curves, with a progressive increase of the variability amplitude with increasing wavelength. We ascribe this redder-when-brighter behaviour to the presence of a "little blue bump" due to line emission from the broad line region, which is clearly visible in the source SED during faint states. Moreover, the data from the XMM-Newton OM reveal a rise of the SED in the UV, suggesting the existence of a "big blue bump" due to thermal emission from the accretion disc. The X-ray spectra are well fitted with a power-law model with photoelectric absorption, possibly larger than the Galactic one. However, the comparison with previous X-ray observations would imply that the amount of absorbing matter is variable. Alternatively, the intrinsic X-ray spectrum presents a curvature, which may depend on the X-ray brightness. In this case, two scenarios are possible.
dc.language.isoen
dc.publisherEDP Sciences
dc.title.enWEBT and XMM-Newton observations of 3C 454.3 during the post-outburst phase. Detection of the little and big blue bumps
dc.typeArticle de revue
dc.subject.halPhysique [physics]/Astrophysique [astro-ph]/Cosmologie et astrophysique extra-galactique [astro-ph.CO]
dc.subject.halPlanète et Univers [physics]/Astrophysique [astro-ph]
dc.identifier.arxiv0708.2793
bordeaux.journalAstronomy and Astrophysics - A&A
bordeaux.page819-827
bordeaux.volume473
bordeaux.issue3
bordeaux.peerReviewedoui
hal.identifierhal-00176467
hal.version1
hal.popularnon
hal.audienceNon spécifiée
dc.subject.esgalaxies: active
dc.subject.esgalaxies: quasars: general
dc.subject.esgalaxies: quasars: individual: 3C 454.3
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-00176467v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Astronomy%20and%20Astrophysics%20-%20A&A&rft.date=2007&rft.volume=473&rft.issue=3&rft.spage=819-827&rft.epage=819-827&rft.eissn=0004-6361&rft.issn=0004-6361&rft.au=RAITERI,%20C.%20M.&VILLATA,%20M.&LARIONOV,%20V.%20M.&PURSIMO,%20T.&IBRAHIMOV,%20M.%20A.&rft.genre=article


Fichier(s) constituant ce document

FichiersTailleFormatVue

Il n'y a pas de fichiers associés à ce document.

Ce document figure dans la(les) collection(s) suivante(s)

Afficher la notice abrégée