Big Fish in Small Ponds: massive stars in the low-mass clusters of M83

Journal Article · Sat Sep 20 04:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/793/1/4· OSTI ID:22365066

Andrews, J. E.; Calzetti, D.; McElwee, Sean ^[1]; Chandar, R. ^[2]; Elmegreen, B. G. ^[3]; Kennicutt, R. C. ^[4]; Kim, Hwihyun ^[5]; Krumholz, Mark R. ^[6]; Lee, J. C.; Whitmore, B. ^[7]

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1. Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)
2. Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States)
3. IBM T. J. Watson Research Center, Yorktown Heights, NY 10598 (United States)
4. Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom)
5. School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1404 (United States)
6. Department of Astronomy and Astrophysics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)
7. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

We have used multi-wavelength Hubble Space Telescope WFC3 data of the starbursting spiral galaxy M83 in order to measure variations in the upper end of the stellar initial mass function (uIMF) using the production rate of ionizing photons in unresolved clusters with ages ≤ 8 Myr. As in earlier papers on M51 and NGC 4214, the uIMF in M83 is consistent with a universal IMF, and stochastic sampling of the stellar populations in the ∼<10{sup 3} M {sub ☉} clusters are responsible for any deviations in this universality. The ensemble cluster population, as well as individual clusters, also imply that the most massive star in a cluster does not depend on the cluster mass. In fact, we have found that these small clusters seem to have an over-abundance of ionizing photons when compared to an expected universal or truncated IMF. This also suggests that the presence of massive stars in these clusters does not affect the star formation in a destructive way.

• OSTI ID: 22365066
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 793; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
ELEMENT ABUNDANCE
GALAXIES
LUMINOSITY
MASS
PHOTONS
SAMPLING
SPACE
STAR CLUSTERS
STARS
STOCHASTIC PROCESSES
TELESCOPES
WAVELENGTHS