THE SNAPSHOT HUBBLE U-BAND CLUSTER SURVEY (SHUCS). II. THE STAR CLUSTER POPULATION OF NGC 2997
2014 (English)In: Astronomical Journal, ISSN 0004-6256, E-ISSN 1538-3881, Vol. 148, no 2, 33- p.Article in journal (Refereed) Published
We study the star cluster population of NGC 2997, a giant spiral galaxy located at 9.5 Mpc and targeted by the Snapshot Hubble U-band Cluster Survey (SHUCS). Combining our U-band imaging from SHUCS with archival BVI imaging from the Hubble Space Telescope, we select a high confidence sample of clusters in the circumnuclear ring and disk through a combination of automatic detection procedures and visual inspection. The cluster luminosity functions in all four filters can be approximated by power laws with indices of -1.7 to -2.3. Some deviations from pure power-law shape are observed, hinting at the presence of a high-mass truncation in the cluster mass function. However, upon inspection of the cluster mass function, we find it is consistent with a pure power law of index -2.2 +/- 0.2 despite a slight bend at similar to 2.5 x 10(4) M-circle dot. No statistically significant truncation is observed. From the cluster age distributions, we find a low rate of disruption(zeta similar to -0.1) in both the disk and circumnuclear ring. Finally, we estimate the cluster formation efficiency (Gamma) over the last 100 Myr in each region, finding 7% +/- 2% for the disk, 12% +/- 4% for the circumnuclear ring, and 10% +/- 3% for the entire UBVI footprint. This study highlights the need for wide-field UBVI coverage of galaxies to study cluster populations in detail, though a small sample of clusters can provide significant insight into the characteristics of the population.
Place, publisher, year, edition, pages
2014. Vol. 148, no 2, 33- p.
galaxies: individual (NGC 2997), galaxies: star clusters: general, galaxies: star formation, surveys
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-106726DOI: 10.1088/0004-6256/148/2/33ISI: 000339324400009OAI: oai:DiVA.org:su-106726DiVA: diva2:738418