Optical microvariability of EGRET blazars

Autores
Romero, Gustavo Esteban; Cellone, Sergio Aldo; Combi, Jorge Ariel; Andruchow, Ileana
Año de publicación
2002
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We present results of a photometric CCD study of the incidence of microvariability in the optical emission of a sample of 20 blazars detected at gamma-ray energies by the EGRET instrument of the Compton Gamma-Ray Observatory. We have observed strong outbursts in some sources, but many others displayed no significant variability on timescales of hours. The typical minimum timescale is found to be of ∼several hours, not tens of minutes as claimed by some authors. The duty cycle for optical intranight microvariations of gamma-ray blazars, as estimated from our observations, seems to be ∼50%, lower than what is usually assumed. For night-to-night variations, instead, the duty cycle approaches that observed in radio-selected BL Lacs and flat-spectrum radio quasars (i.e. ∼70%).
Facultad de Ciencias Astronómicas y Geofísicas
Instituto Argentino de Radioastronomía
Materia
Ciencias Astronómicas
BL Lacertae objects: general
Galaxies: active
Galaxies: photometry
Gamma-rays: observations
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/84617

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network_name_str SEDICI (UNLP)
spelling Optical microvariability of EGRET blazarsRomero, Gustavo EstebanCellone, Sergio AldoCombi, Jorge ArielAndruchow, IleanaCiencias AstronómicasBL Lacertae objects: generalGalaxies: activeGalaxies: photometryGamma-rays: observationsWe present results of a photometric CCD study of the incidence of microvariability in the optical emission of a sample of 20 blazars detected at gamma-ray energies by the EGRET instrument of the Compton Gamma-Ray Observatory. We have observed strong outbursts in some sources, but many others displayed no significant variability on timescales of hours. The typical minimum timescale is found to be of ∼several hours, not tens of minutes as claimed by some authors. The duty cycle for optical intranight microvariations of gamma-ray blazars, as estimated from our observations, seems to be ∼50%, lower than what is usually assumed. For night-to-night variations, instead, the duty cycle approaches that observed in radio-selected BL Lacs and flat-spectrum radio quasars (i.e. ∼70%).Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomía2002info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf431-438http://sedici.unlp.edu.ar/handle/10915/84617enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20020743info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:16:16Zoai:sedici.unlp.edu.ar:10915/84617Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:16.326SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Optical microvariability of EGRET blazars
title Optical microvariability of EGRET blazars
spellingShingle Optical microvariability of EGRET blazars
Romero, Gustavo Esteban
Ciencias Astronómicas
BL Lacertae objects: general
Galaxies: active
Galaxies: photometry
Gamma-rays: observations
title_short Optical microvariability of EGRET blazars
title_full Optical microvariability of EGRET blazars
title_fullStr Optical microvariability of EGRET blazars
title_full_unstemmed Optical microvariability of EGRET blazars
title_sort Optical microvariability of EGRET blazars
dc.creator.none.fl_str_mv Romero, Gustavo Esteban
Cellone, Sergio Aldo
Combi, Jorge Ariel
Andruchow, Ileana
author Romero, Gustavo Esteban
author_facet Romero, Gustavo Esteban
Cellone, Sergio Aldo
Combi, Jorge Ariel
Andruchow, Ileana
author_role author
author2 Cellone, Sergio Aldo
Combi, Jorge Ariel
Andruchow, Ileana
author2_role author
author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
BL Lacertae objects: general
Galaxies: active
Galaxies: photometry
Gamma-rays: observations
topic Ciencias Astronómicas
BL Lacertae objects: general
Galaxies: active
Galaxies: photometry
Gamma-rays: observations
dc.description.none.fl_txt_mv We present results of a photometric CCD study of the incidence of microvariability in the optical emission of a sample of 20 blazars detected at gamma-ray energies by the EGRET instrument of the Compton Gamma-Ray Observatory. We have observed strong outbursts in some sources, but many others displayed no significant variability on timescales of hours. The typical minimum timescale is found to be of ∼several hours, not tens of minutes as claimed by some authors. The duty cycle for optical intranight microvariations of gamma-ray blazars, as estimated from our observations, seems to be ∼50%, lower than what is usually assumed. For night-to-night variations, instead, the duty cycle approaches that observed in radio-selected BL Lacs and flat-spectrum radio quasars (i.e. ∼70%).
Facultad de Ciencias Astronómicas y Geofísicas
Instituto Argentino de Radioastronomía
description We present results of a photometric CCD study of the incidence of microvariability in the optical emission of a sample of 20 blazars detected at gamma-ray energies by the EGRET instrument of the Compton Gamma-Ray Observatory. We have observed strong outbursts in some sources, but many others displayed no significant variability on timescales of hours. The typical minimum timescale is found to be of ∼several hours, not tens of minutes as claimed by some authors. The duty cycle for optical intranight microvariations of gamma-ray blazars, as estimated from our observations, seems to be ∼50%, lower than what is usually assumed. For night-to-night variations, instead, the duty cycle approaches that observed in radio-selected BL Lacs and flat-spectrum radio quasars (i.e. ∼70%).
publishDate 2002
dc.date.none.fl_str_mv 2002
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/84617
url http://sedici.unlp.edu.ar/handle/10915/84617
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0004-6361
info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20020743
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
dc.format.none.fl_str_mv application/pdf
431-438
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
instacron_str UNLP
institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
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