Recent star formation in several galaxies of the tidally disturbed system HCG 31

Citation
Ke. Johnson et Ps. Conti, Recent star formation in several galaxies of the tidally disturbed system HCG 31, ASTRONOM J, 119(5), 2000, pp. 2146-2153
Citations number
40
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMICAL JOURNAL
ISSN journal
00046256 → ACNP
Volume
119
Issue
5
Year of publication
2000
Pages
2146 - 2153
Database
ISI
SICI code
0004-6256(200005)119:5<2146:RSFISG>2.0.ZU;2-Y
Abstract
High-resolution (0." 7 to 0." 8) H alpha images of the Hickson Compact Grou p 31 (HCG 31) obtained with the WIYN telescope are used in conjunction with broadband optical images from the Hubble Space Telescope (HST) to examine the star formation history and properties of the component galaxies. The hi gh spatial resolution of the WIYN telescope has allowed us to identify a la rge number of starburst regions from their H alpha emission, which traces t he recent star birth activity. The HST images of galaxies E and F reveal mo re detail within the starburst regions in which we have identified numerous super star clusters (SSCs). Photometry of these starburst regions and SSCs in the H alpha and optical images indicates that there has been a substant ial amount of star formation throughout HGC 31 over the past 10 Myr. The H alpha equivalent widths suggest activity within the group as recently as a few megayears ago. There is evidence that galaxy F, the youngest member of the group, is possibly undergoing its initial episode of star formation, as no underlying stellar population has yet been detected.