GALEX UV color relations for nearby early-type galaxies

We use GALEX/optical photometry to construct color-color relationships for early-type galaxies sorted by morphological type. We have matched objects in the GALEX GR1 public release and the first IR1.1 internal release, with the RC3 early-type galaxies having a morphological type -5.5 ≤ T < − 1.5,...

Descripción completa

Detalles Bibliográficos
Autor: Gil De Paz, Armando
Tipo de recurso: artículo
Fecha de publicación:2007
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/51760
Acceso en línea:https://hdl.handle.net/20.500.14352/51760
Access Level:acceso abierto
Palabra clave:52
Old stellar populations
Elliptic galaxies
Evolution-explorer
Star-formation
Local universe
Ultraviolet
Photometry
Cluster
Sample
M32
Astrofísica
Electricidad
2202.03 Electricidad
id ES_e7286cd7cf7ef4f2c0743adecf7225ae
oai_identifier_str oai:docta.ucm.es:20.500.14352/51760
network_acronym_str ES
network_name_str España
repository_id_str
spelling GALEX UV color relations for nearby early-type galaxiesGil De Paz, Armando52Old stellar populationsElliptic galaxiesEvolution-explorerStar-formationLocal universeUltravioletPhotometryClusterSampleM32AstrofísicaElectricidad2202.03 ElectricidadWe use GALEX/optical photometry to construct color-color relationships for early-type galaxies sorted by morphological type. We have matched objects in the GALEX GR1 public release and the first IR1.1 internal release, with the RC3 early-type galaxies having a morphological type -5.5 ≤ T < − 1.5, with mean error on T < 1.5 and mean error on (B − V)_T < 0.05. After visual inspection of each match, we are left with 130 galaxies with reliable GALEX pipeline photometry in the far-UV and near-UV bands. This sample is divided into ellipticals (-5.5 ≤ T < − 3.5) and lenticulars (-3.5 ≤ T < − 1.5). After correction for Galactic extinction, the color-color diagrams FUV − NUV versus (B − V)_Tc are plotted for the two subsamples. We find a tight anticorrelation between the FUV − NUV and (B − V)Tc colors for ellipticals, with the UV color getting bluer when the (B − V)Tc gets redder. This relationship very likely is an extension of the color-metallicity relationship in the GALEX NUV band. We suspect that the main source of the correlation is metal line blanketing in the NUV band. The FUV − NUV versus B − V correlation has larger scatter for lenticular galaxies; we speculate that this reflects the presence of low-level star formation. If the latter objects (i.e., those that are blue both in FUV − NUV and in B − V) are interpreted as harboring recent star formation activity, this would be the case for a few percent (~4%) of ellipticals and ~15% of lenticulars; this would mean about 10% of early-type galaxies have residual star formation in our full sample of 130 early-type galaxies. We also plot FUV − NUV versus the Mg2 index and central velocity dispersion. We find a tight anticorrelation between FUV − NUV and the Mg2 index; we suspect that this reflects blanketing in the NUV band being correlated with overall metallicity. We find a marginal anticorrelation of FUV − V_T with Mg_2 for elliptical galaxies.University Chicago PressUniversidad Complutense de Madrid20072007-12-0120072007-12-01journal articlehttp://purl.org/coar/resource_type/c_6501info:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/20.500.14352/51760reponame:Docta Complutenseinstname:Universidad Complutense de Madrid (UCM)Inglésengopen accesshttp://purl.org/coar/access_right/c_abf2info:eu-repo/semantics/openAccessoai:docta.ucm.es:20.500.14352/517602026-06-02T12:44:21Z
dc.title.none.fl_str_mv GALEX UV color relations for nearby early-type galaxies
title GALEX UV color relations for nearby early-type galaxies
spellingShingle GALEX UV color relations for nearby early-type galaxies
Gil De Paz, Armando
52
Old stellar populations
Elliptic galaxies
Evolution-explorer
Star-formation
Local universe
Ultraviolet
Photometry
Cluster
Sample
M32
Astrofísica
Electricidad
2202.03 Electricidad
title_short GALEX UV color relations for nearby early-type galaxies
title_full GALEX UV color relations for nearby early-type galaxies
title_fullStr GALEX UV color relations for nearby early-type galaxies
title_full_unstemmed GALEX UV color relations for nearby early-type galaxies
title_sort GALEX UV color relations for nearby early-type galaxies
dc.creator.none.fl_str_mv Gil De Paz, Armando
author Gil De Paz, Armando
author_facet Gil De Paz, Armando
author_role author
dc.contributor.none.fl_str_mv Universidad Complutense de Madrid
dc.subject.none.fl_str_mv 52
Old stellar populations
Elliptic galaxies
Evolution-explorer
Star-formation
Local universe
Ultraviolet
Photometry
Cluster
Sample
M32
Astrofísica
Electricidad
2202.03 Electricidad
topic 52
Old stellar populations
Elliptic galaxies
Evolution-explorer
Star-formation
Local universe
Ultraviolet
Photometry
Cluster
Sample
M32
Astrofísica
Electricidad
2202.03 Electricidad
description We use GALEX/optical photometry to construct color-color relationships for early-type galaxies sorted by morphological type. We have matched objects in the GALEX GR1 public release and the first IR1.1 internal release, with the RC3 early-type galaxies having a morphological type -5.5 ≤ T < − 1.5, with mean error on T < 1.5 and mean error on (B − V)_T < 0.05. After visual inspection of each match, we are left with 130 galaxies with reliable GALEX pipeline photometry in the far-UV and near-UV bands. This sample is divided into ellipticals (-5.5 ≤ T < − 3.5) and lenticulars (-3.5 ≤ T < − 1.5). After correction for Galactic extinction, the color-color diagrams FUV − NUV versus (B − V)_Tc are plotted for the two subsamples. We find a tight anticorrelation between the FUV − NUV and (B − V)Tc colors for ellipticals, with the UV color getting bluer when the (B − V)Tc gets redder. This relationship very likely is an extension of the color-metallicity relationship in the GALEX NUV band. We suspect that the main source of the correlation is metal line blanketing in the NUV band. The FUV − NUV versus B − V correlation has larger scatter for lenticular galaxies; we speculate that this reflects the presence of low-level star formation. If the latter objects (i.e., those that are blue both in FUV − NUV and in B − V) are interpreted as harboring recent star formation activity, this would be the case for a few percent (~4%) of ellipticals and ~15% of lenticulars; this would mean about 10% of early-type galaxies have residual star formation in our full sample of 130 early-type galaxies. We also plot FUV − NUV versus the Mg2 index and central velocity dispersion. We find a tight anticorrelation between FUV − NUV and the Mg2 index; we suspect that this reflects blanketing in the NUV band being correlated with overall metallicity. We find a marginal anticorrelation of FUV − V_T with Mg_2 for elliptical galaxies.
publishDate 2007
dc.date.none.fl_str_mv 2007
2007-12-01
2007
2007-12-01
dc.type.none.fl_str_mv journal article
http://purl.org/coar/resource_type/c_6501
dc.type.openaire.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv https://hdl.handle.net/20.500.14352/51760
url https://hdl.handle.net/20.500.14352/51760
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
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
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv University Chicago Press
publisher.none.fl_str_mv University Chicago Press
dc.source.none.fl_str_mv reponame:Docta Complutense
instname:Universidad Complutense de Madrid (UCM)
instname_str Universidad Complutense de Madrid (UCM)
reponame_str Docta Complutense
collection Docta Complutense
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869422830129512448
score 15,300719

Similares en LA Referencia