Morphology of star formation regions in irregular galaxies

Jul, 1998
28 pages
Published in:
  • Mon.Not.Roy.Astron.Soc. 300 (1998) 1091
e-Print:

Citations per year

19992002200520082009120
Abstract: (arXiv)
The location of HII regions, which indicates the locus of present star formation in galaxies, is analyzed for a large collection of 110 irregular galaxies (Irr) imaged in Hα\alpha and nearby continuum. The analysis is primarily by visual inspection, although a two-dimensional quantitative measure is also employed. The two different analyses yield essentially identical results. HII regions appear preferentially at the edges of the light distribution, predominantly on one side of the galaxy, contrary to what is expected from stochastic self-propagating star formation scenarios. This peculiar distribution of star forming regions cannot be explained by a scenario of star formation triggered by an interaction with extragalactic gas, or by a strong one-armed spiral pattern.