Ultracompact dwarfs around NGC3258 in the Antlia cluster

Autores
Caso, Juan Pablo; Bassino, Lilia Patricia; Richtler, Tom; Smith Castelli, Analía Viviana; Faifer, Favio Raúl
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We present the first compact stellar systems with luminosities in the range of ultracompact dwarfs (UCDs), discovered in the Antlia galaxy cluster (-10.5V <-11.6). The magnitude limit between UCDs and globular clusters (CGs) is discussed. By means of imaging from VLT (FORS1), CTIO (MOSAIC) and the Hubble Space Telescope (ACS) archive, 11 UCDs/bright GCs are selected on the basis of photometry and confirmed as Antlia members through radial velocities measured on new Gemini (GMOS) spectra. In addition, nine UCD candidates are identified taking into account properties derived from their surface brightness profiles. All of them, members and candidates, are located in the proximity of NGC3258, one of the two brightest elliptical galaxies in the cluster core. Antlia UCDs in this sample present absolute magnitudes fainter than MV ~ -11.6 mag and most of them have colours within the blue GC range, falling only two within the red GC range. Effective radii measured for the ones lying on the ACS field are in the range Reff = 3-11 pc and are similar to equivalent objects in other clusters, obtained from the literature. The UCD sample shares the same behaviour on the size-luminosity plane: a linear relation between Reff and MV is present for UCDs brighter than MV~ -10.5 to -11 mag while no trend is detected for fainter ones, that have an approximately constant Reff. The projected spatial distribution of UCDs, GCs and X-ray emission points to an ongoing merger between two Antlia groups, dominated by NGC3258 and NGC3268. Nuclei of dwarf elliptical galaxies and blue UCDs share the same locus on the colour-magnitude diagram, supporting the hypothesis that some blue UCDs may be remnants of stripped nucleated dwarfs.
Instituto de Astrofísica de La Plata
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Ciencias Astronómicas
Galaxies: clusters: individual: Antlia
Galaxies: Dwarf
Galaxies: Individual: NGC 3258
Galaxies: photometry
Galaxies: Star clusters: General
Glaxies: Nuclei
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:10915/85491
Acceder
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oai_identifier_str oai:sedici.unlp.edu.ar:10915/85491
network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling Ultracompact dwarfs around NGC3258 in the Antlia clusterCaso, Juan PabloBassino, Lilia PatriciaRichtler, TomSmith Castelli, Analía VivianaFaifer, Favio RaúlCiencias AstronómicasGalaxies: clusters: individual: AntliaGalaxies: DwarfGalaxies: Individual: NGC 3258Galaxies: photometryGalaxies: Star clusters: GeneralGlaxies: NucleiWe present the first compact stellar systems with luminosities in the range of ultracompact dwarfs (UCDs), discovered in the Antlia galaxy cluster (-10.5<M<sub>V</sub> <-11.6). The magnitude limit between UCDs and globular clusters (CGs) is discussed. By means of imaging from VLT (FORS1), CTIO (MOSAIC) and the Hubble Space Telescope (ACS) archive, 11 UCDs/bright GCs are selected on the basis of photometry and confirmed as Antlia members through radial velocities measured on new Gemini (GMOS) spectra. In addition, nine UCD candidates are identified taking into account properties derived from their surface brightness profiles. All of them, members and candidates, are located in the proximity of NGC3258, one of the two brightest elliptical galaxies in the cluster core. Antlia UCDs in this sample present absolute magnitudes fainter than M<sub>V</sub> ~ -11.6 mag and most of them have colours within the blue GC range, falling only two within the red GC range. Effective radii measured for the ones lying on the ACS field are in the range R<sub>eff</sub> = 3-11 pc and are similar to equivalent objects in other clusters, obtained from the literature. The UCD sample shares the same behaviour on the size-luminosity plane: a linear relation between R<sub>eff</sub> and MV is present for UCDs brighter than M<sub>V</sub>~ -10.5 to -11 mag while no trend is detected for fainter ones, that have an approximately constant Reff. The projected spatial distribution of UCDs, GCs and X-ray emission points to an ongoing merger between two Antlia groups, dominated by NGC3258 and NGC3268. Nuclei of dwarf elliptical galaxies and blue UCDs share the same locus on the colour-magnitude diagram, supporting the hypothesis that some blue UCDs may be remnants of stripped nucleated dwarfs.Instituto de Astrofísica de La PlataFacultad de Ciencias Astronómicas y Geofísicas2013info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf1088-1101http://sedici.unlp.edu.ar/handle/10915/85491enginfo:eu-repo/semantics/altIdentifier/issn/0035-8711info:eu-repo/semantics/altIdentifier/doi/10.1093/mnras/sts687info: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:UNLP2025-09-29T11:16:30Zoai:sedici.unlp.edu.ar:10915/85491Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:31.05SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Ultracompact dwarfs around NGC3258 in the Antlia cluster
title Ultracompact dwarfs around NGC3258 in the Antlia cluster
spellingShingle Ultracompact dwarfs around NGC3258 in the Antlia cluster
Caso, Juan Pablo
Ciencias Astronómicas
Galaxies: clusters: individual: Antlia
Galaxies: Dwarf
Galaxies: Individual: NGC 3258
Galaxies: photometry
Galaxies: Star clusters: General
Glaxies: Nuclei
title_short Ultracompact dwarfs around NGC3258 in the Antlia cluster
title_full Ultracompact dwarfs around NGC3258 in the Antlia cluster
title_fullStr Ultracompact dwarfs around NGC3258 in the Antlia cluster
title_full_unstemmed Ultracompact dwarfs around NGC3258 in the Antlia cluster
title_sort Ultracompact dwarfs around NGC3258 in the Antlia cluster
dc.creator.none.fl_str_mv Caso, Juan Pablo
Bassino, Lilia Patricia
Richtler, Tom
Smith Castelli, Analía Viviana
Faifer, Favio Raúl
author Caso, Juan Pablo
author_facet Caso, Juan Pablo
Bassino, Lilia Patricia
Richtler, Tom
Smith Castelli, Analía Viviana
Faifer, Favio Raúl
author_role author
author2 Bassino, Lilia Patricia
Richtler, Tom
Smith Castelli, Analía Viviana
Faifer, Favio Raúl
author2_role author
author
author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
Galaxies: clusters: individual: Antlia
Galaxies: Dwarf
Galaxies: Individual: NGC 3258
Galaxies: photometry
Galaxies: Star clusters: General
Glaxies: Nuclei
topic Ciencias Astronómicas
Galaxies: clusters: individual: Antlia
Galaxies: Dwarf
Galaxies: Individual: NGC 3258
Galaxies: photometry
Galaxies: Star clusters: General
Glaxies: Nuclei
dc.description.none.fl_txt_mv We present the first compact stellar systems with luminosities in the range of ultracompact dwarfs (UCDs), discovered in the Antlia galaxy cluster (-10.5<M<sub>V</sub> <-11.6). The magnitude limit between UCDs and globular clusters (CGs) is discussed. By means of imaging from VLT (FORS1), CTIO (MOSAIC) and the Hubble Space Telescope (ACS) archive, 11 UCDs/bright GCs are selected on the basis of photometry and confirmed as Antlia members through radial velocities measured on new Gemini (GMOS) spectra. In addition, nine UCD candidates are identified taking into account properties derived from their surface brightness profiles. All of them, members and candidates, are located in the proximity of NGC3258, one of the two brightest elliptical galaxies in the cluster core. Antlia UCDs in this sample present absolute magnitudes fainter than M<sub>V</sub> ~ -11.6 mag and most of them have colours within the blue GC range, falling only two within the red GC range. Effective radii measured for the ones lying on the ACS field are in the range R<sub>eff</sub> = 3-11 pc and are similar to equivalent objects in other clusters, obtained from the literature. The UCD sample shares the same behaviour on the size-luminosity plane: a linear relation between R<sub>eff</sub> and MV is present for UCDs brighter than M<sub>V</sub>~ -10.5 to -11 mag while no trend is detected for fainter ones, that have an approximately constant Reff. The projected spatial distribution of UCDs, GCs and X-ray emission points to an ongoing merger between two Antlia groups, dominated by NGC3258 and NGC3268. Nuclei of dwarf elliptical galaxies and blue UCDs share the same locus on the colour-magnitude diagram, supporting the hypothesis that some blue UCDs may be remnants of stripped nucleated dwarfs.
Instituto de Astrofísica de La Plata
Facultad de Ciencias Astronómicas y Geofísicas
description We present the first compact stellar systems with luminosities in the range of ultracompact dwarfs (UCDs), discovered in the Antlia galaxy cluster (-10.5<M<sub>V</sub> <-11.6). The magnitude limit between UCDs and globular clusters (CGs) is discussed. By means of imaging from VLT (FORS1), CTIO (MOSAIC) and the Hubble Space Telescope (ACS) archive, 11 UCDs/bright GCs are selected on the basis of photometry and confirmed as Antlia members through radial velocities measured on new Gemini (GMOS) spectra. In addition, nine UCD candidates are identified taking into account properties derived from their surface brightness profiles. All of them, members and candidates, are located in the proximity of NGC3258, one of the two brightest elliptical galaxies in the cluster core. Antlia UCDs in this sample present absolute magnitudes fainter than M<sub>V</sub> ~ -11.6 mag and most of them have colours within the blue GC range, falling only two within the red GC range. Effective radii measured for the ones lying on the ACS field are in the range R<sub>eff</sub> = 3-11 pc and are similar to equivalent objects in other clusters, obtained from the literature. The UCD sample shares the same behaviour on the size-luminosity plane: a linear relation between R<sub>eff</sub> and MV is present for UCDs brighter than M<sub>V</sub>~ -10.5 to -11 mag while no trend is detected for fainter ones, that have an approximately constant Reff. The projected spatial distribution of UCDs, GCs and X-ray emission points to an ongoing merger between two Antlia groups, dominated by NGC3258 and NGC3268. Nuclei of dwarf elliptical galaxies and blue UCDs share the same locus on the colour-magnitude diagram, supporting the hypothesis that some blue UCDs may be remnants of stripped nucleated dwarfs.
publishDate 2013
dc.date.none.fl_str_mv 2013
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/10915/85491
url http://sedici.unlp.edu.ar/handle/10915/85491
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0035-8711
info:eu-repo/semantics/altIdentifier/doi/10.1093/mnras/sts687
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
1088-1101
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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score 13.069144

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