Ultracompact dwarfs around NGC3258 in the Antlia cluster
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 (...
| Autores principales: | , , , , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
2013
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/85491 |
| Aporte de: |
| id |
I19-R120-10915-85491 |
|---|---|
| record_format |
dspace |
| institution |
Universidad Nacional de La Plata |
| institution_str |
I-19 |
| repository_str |
R-120 |
| collection |
SEDICI (UNLP) |
| language |
Inglés |
| topic |
Ciencias Astronómicas Galaxies: clusters: individual: Antlia Galaxies: Dwarf Galaxies: Individual: NGC 3258 Galaxies: photometry Galaxies: Star clusters: General Glaxies: Nuclei |
| spellingShingle |
Ciencias Astronómicas Galaxies: clusters: individual: Antlia Galaxies: Dwarf Galaxies: Individual: NGC 3258 Galaxies: photometry Galaxies: Star clusters: General Glaxies: Nuclei Caso, Juan Pablo Bassino, Lilia Patricia Richtler, Tom Smith Castelli, Analía Viviana Faifer, Favio Raúl Ultracompact dwarfs around NGC3258 in the Antlia cluster |
| topic_facet |
Ciencias Astronómicas Galaxies: clusters: individual: Antlia Galaxies: Dwarf Galaxies: Individual: NGC 3258 Galaxies: photometry Galaxies: Star clusters: General Glaxies: Nuclei |
| 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. |
| format |
Articulo Articulo |
| author |
Caso, Juan Pablo Bassino, Lilia Patricia Richtler, Tom Smith Castelli, Analía Viviana Faifer, Favio Raúl |
| author_facet |
Caso, Juan Pablo Bassino, Lilia Patricia Richtler, Tom Smith Castelli, Analía Viviana Faifer, Favio Raúl |
| author_sort |
Caso, Juan Pablo |
| title |
Ultracompact dwarfs around NGC3258 in the Antlia cluster |
| 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 |
| publishDate |
2013 |
| url |
http://sedici.unlp.edu.ar/handle/10915/85491 |
| work_keys_str_mv |
AT casojuanpablo ultracompactdwarfsaroundngc3258intheantliacluster AT bassinoliliapatricia ultracompactdwarfsaroundngc3258intheantliacluster AT richtlertom ultracompactdwarfsaroundngc3258intheantliacluster AT smithcastellianaliaviviana ultracompactdwarfsaroundngc3258intheantliacluster AT faiferfavioraul ultracompactdwarfsaroundngc3258intheantliacluster |
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Repositorios |
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