HST observations of star clusters in NGC 3256

DOI

We use the Advanced Camera for Surveys on the Hubble Space Telescope to study the rich population of young massive star clusters in the main body of NGC 3256, a merging pair of galaxies with a high star formation rate (SFR) and SFR per unit area ({Sigma}SFR). These clusters have luminosity and mass functions that follow power laws, dN/dL{propto}L^{alpha}^ with {alpha}=-2.23+/-0.07, and dN/dM{propto}M^{beta}^ with {beta}=-1.86+/-0.34 for {tau}<10Myr clusters, similar to those found in more quiescent galaxies. The age distribution can be described by dN/d{tau}{propto}{tau}^{gamma}^, with {gamma}~-0.67+/-0.08 for clusters younger than about a few hundred million years, with no obvious dependence on cluster mass. This is consistent with a picture where ~80% of the clusters are disrupted each decade in time. We investigate the claim that galaxies with high {Sigma}SFR form clusters more efficiently than quiescent systems by determining the fraction of stars in bound clusters ({Gamma}) and the CMF/SFR statistic (CMF is the cluster mass function) for NGC 3256 and comparing the results with those for other galaxies. We find that the CMF/SFR statistic for NGC 3256 agrees well with that found for galaxies with {Sigma}SFR and SFRs that are lower by 1-3 orders of magnitude, but that estimates for {Gamma} are only robust when the same sets of assumptions are applied. Currently, {Gamma} values available in the literature have used different sets of assumptions, making it more difficult to compare the results between galaxies.

Cone search capability for table J/ApJ/826/32/table1 (Catalog of candidate star clusters in NGC 3256)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18260032
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/826/32
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/826/32
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/826/32
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/826/32
Provenance
Creator Mulia A.J.; Chandar R.; Whitmore B.C.
Publisher CDS
Publication Year 2016
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Galactic and extragalactic Astronomy; Natural Sciences; Observational Astronomy; Physics