Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution

From Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton, NuSTAR, and Hubble Space Telescope (HST) observations to study this event. Here in the first paper of our series we pr...

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Detalles Bibliográficos
Autor: Marco, Barbara de|||0000-0003-2743-6632
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/356660
Acceso en línea:https://hdl.handle.net/2117/356660
https://dx.doi.org/10.1051/0004-6361/202141324
Access Level:acceso abierto
Palabra clave:X-rays: galaxies
Galaxies: active
Galaxies: Seyfert
Accretion
Accretion disks
Techniques: spectroscopic
Raigs X
Astrofísica
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
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network_acronym_str ES
network_name_str España
repository_id_str
spelling Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distributionMarco, Barbara de|||0000-0003-2743-6632X-rays: galaxiesGalaxies: activeGalaxies: SeyfertAccretionAccretion disksTechniques: spectroscopicRaigs XAstrofísicaÀrees temàtiques de la UPC::Física::Astronomia i astrofísicaFrom Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton, NuSTAR, and Hubble Space Telescope (HST) observations to study this event. Here in the first paper of our series we present the broadband continuum modelling of the spectral energy distribution (SED) for NGC 3227, extending from near infrared (NIR) to hard X-rays. We use our new spectra taken with XMM-Newton, NuSTAR, and HST/COS in 2019, together with archival unobscured XMM-Newton, NuSTAR, and HST/STIS data, in order to disentangle various spectral components of NGC 3227 and recover the underlying continuum. We find the observed NIR-optical-UV continuum is explained well by an accretion disk blackbody component (Tmax = 10 eV), which is internally reddened by E(B-V) = 0.45 with a Small Magellanic Cloud (SMC) extinction law. We derive the inner radius (12 Rg) and the accretion rate (0.1 solar mass per year) of the disk by modelling the thermal disk emission. The internal reddening in NGC 3227 is most likely associated with outflows from the dusty AGN torus. In addition, an unreddened continuum component is also evident, which likely arises from scattered radiation, associated with the extended narrow-line region (NLR) of NGC 3227. The extreme ultraviolet (EUV) continuum, and the 'soft X-ray excess', can be explained with a 'warm Comptonisation' component. The hard X-rays are consistent with a power-law and a neutral reflection component. The intrinsic bolometric luminosity of the AGN in NGC 3227 is about 2.2e+43 erg/s in 2019, corresponding to 3% Eddington luminosity. Our continuum modelling of the new triggered data of NGC 3227 requires the presence of a new obscuring gas with column density NH = 5e+22 cm^-2, partially covering the X-ray source (Cf = 0.6).Peer ReviewedEDP Sciences20212021-08-0120212021-11-18journal articlehttp://purl.org/coar/resource_type/c_6501AMhttp://purl.org/coar/version/c_ab4af688f83e57aainfo:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/2117/356660https://dx.doi.org/10.1051/0004-6361/202141324reponame:UPCommons. Portal del coneixement obert de la UPCinstname:Universitat Politècnica de Catalunya (UPC)Inglésengopen accesshttp://purl.org/coar/access_right/c_abf2Attribution-NonCommercial-NoDerivs 3.0 Spainhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/info:eu-repo/semantics/openAccessoai:upcommons.upc.edu:2117/3566602026-05-27T15:37:01Z
dc.title.none.fl_str_mv Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
title Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
spellingShingle Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
Marco, Barbara de|||0000-0003-2743-6632
X-rays: galaxies
Galaxies: active
Galaxies: Seyfert
Accretion
Accretion disks
Techniques: spectroscopic
Raigs X
Astrofísica
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
title_short Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
title_full Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
title_fullStr Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
title_full_unstemmed Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
title_sort Transient obscuration event captured in NGC 3227: I. Continuum model for the broadband spectral energy distribution
dc.creator.none.fl_str_mv Marco, Barbara de|||0000-0003-2743-6632
author Marco, Barbara de|||0000-0003-2743-6632
author_facet Marco, Barbara de|||0000-0003-2743-6632
author_role author
dc.subject.none.fl_str_mv X-rays: galaxies
Galaxies: active
Galaxies: Seyfert
Accretion
Accretion disks
Techniques: spectroscopic
Raigs X
Astrofísica
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
topic X-rays: galaxies
Galaxies: active
Galaxies: Seyfert
Accretion
Accretion disks
Techniques: spectroscopic
Raigs X
Astrofísica
Àrees temàtiques de la UPC::Física::Astronomia i astrofísica
description From Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton, NuSTAR, and Hubble Space Telescope (HST) observations to study this event. Here in the first paper of our series we present the broadband continuum modelling of the spectral energy distribution (SED) for NGC 3227, extending from near infrared (NIR) to hard X-rays. We use our new spectra taken with XMM-Newton, NuSTAR, and HST/COS in 2019, together with archival unobscured XMM-Newton, NuSTAR, and HST/STIS data, in order to disentangle various spectral components of NGC 3227 and recover the underlying continuum. We find the observed NIR-optical-UV continuum is explained well by an accretion disk blackbody component (Tmax = 10 eV), which is internally reddened by E(B-V) = 0.45 with a Small Magellanic Cloud (SMC) extinction law. We derive the inner radius (12 Rg) and the accretion rate (0.1 solar mass per year) of the disk by modelling the thermal disk emission. The internal reddening in NGC 3227 is most likely associated with outflows from the dusty AGN torus. In addition, an unreddened continuum component is also evident, which likely arises from scattered radiation, associated with the extended narrow-line region (NLR) of NGC 3227. The extreme ultraviolet (EUV) continuum, and the 'soft X-ray excess', can be explained with a 'warm Comptonisation' component. The hard X-rays are consistent with a power-law and a neutral reflection component. The intrinsic bolometric luminosity of the AGN in NGC 3227 is about 2.2e+43 erg/s in 2019, corresponding to 3% Eddington luminosity. Our continuum modelling of the new triggered data of NGC 3227 requires the presence of a new obscuring gas with column density NH = 5e+22 cm^-2, partially covering the X-ray source (Cf = 0.6).
publishDate 2021
dc.date.none.fl_str_mv 2021
2021-08-01
2021
2021-11-18
dc.type.none.fl_str_mv journal article
http://purl.org/coar/resource_type/c_6501
AM
http://purl.org/coar/version/c_ab4af688f83e57aa
dc.type.openaire.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv https://hdl.handle.net/2117/356660
https://dx.doi.org/10.1051/0004-6361/202141324
url https://hdl.handle.net/2117/356660
https://dx.doi.org/10.1051/0004-6361/202141324
dc.language.none.fl_str_mv Inglés
eng
language_invalid_str_mv Inglés
language eng
dc.rights.none.fl_str_mv open access
http://purl.org/coar/access_right/c_abf2
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/
dc.rights.openaire.fl_str_mv info:eu-repo/semantics/openAccess
rights_invalid_str_mv open access
http://purl.org/coar/access_right/c_abf2
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv EDP Sciences
publisher.none.fl_str_mv EDP Sciences
dc.source.none.fl_str_mv reponame:UPCommons. Portal del coneixement obert de la UPC
instname:Universitat Politècnica de Catalunya (UPC)
instname_str Universitat Politècnica de Catalunya (UPC)
reponame_str UPCommons. Portal del coneixement obert de la UPC
collection UPCommons. Portal del coneixement obert de la UPC
repository.name.fl_str_mv
repository.mail.fl_str_mv
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