The ages of M31 star clusters: SED versus CMD Virtual Observatory Resource

Authors
  1. Fan Z.
  2. Li Z.
  3. Zhao G.
  4. Published by
    CDS
Abstract

It is well-known that fitting Color-Magnitude Diagrams (CMDs) to theoretical isochrones is the main method to determine star cluster ages. However, when CMDs are not available, the Spectral Energy Distribution (SED)-fitting technique is the only other approach, although it suffers the age-metallicity-reddening degeneracy. In this work, we gather the ages, metallicities, and masses of dozens of M31 star clusters from the CMD-fitting with Hubble Space Telescope images from the literature for comparison. We check the reliability of the SED-fitting results with different models, i.e., Bruzual & Charlot (2003MNRAS.344.1000B) model (BC03), Galaxy Evolutionary Synthesis Models (GALEV), and Advanced Stellar Population Synthesis (ASPS) for the simple stellar populations (SSPs) with single stars (ss)-SSP/binary-star (bs)-SSPs models. The photometry bands includes the Galaxy Evolution Explorer GALEX FUV/NUV bands, optical/near-infrared UBVRIJHK bands, as well as the Wide-field Infrared Survey Explorer (WISE) W1/W2 bands. The comparisons show that the SED-fitting ages agree well with the CMD-fitting ages, either with the fixed metallicity or with the free metallicity for both the BC03 and the GALEV model. However, for the ASPS models, it seems that SED-fitting results are systematically older than the CMD ages, especially for the ages log t<9.0 (year). The fitting also shows that the GALEX FUV/NUV-band are more important than the WISE W1/W2 for constraining the ages, which confirms the previous findings. We also derived the masses of our sample star clusters from the BC03 and GALEV models and it is found that the values agree well with those in the literature.

Keywords
  1. Galaxies
  2. Globular star clusters
  3. Metallicity
  4. Stellar ages
  5. Stellar masses
  6. Astronomical models
Bibliographic source Bibcode
2018AJ....156..191F
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/156/191
IVOA Identifier IVOID
ivo://CDS.VizieR/J/AJ/156/191
Document Object Identifer DOI
doi:10.26093/cds/vizier.51560191

Access

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http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/156/191
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/156/191
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/156/191
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Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/156/191/table1?
https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/156/191/table1?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/156/191/table1?

History

2019-04-02T07:34:03Z
Resource record created
2019-04-02T07:34:03Z
Created
2019-05-06T14:36:30Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr