Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-05-20
Astrophys.J. 644 (2006) 879-889
Astronomy and Astrophysics
Astrophysics
28 pages, 11 figures, ApJ, 644, June 20, 2006
Scientific paper
10.1086/503797
The distributions of size and luminosity for star-forming regions in the nearby spiral galaxy NGC 628 are studied over a wide range of scales using progressively blurred versions of an image from the Hubble Space Telescope Advanced Camera for Surveys. Four optical filters are considered for the central region, including Halpha. Two filters are used for an outer region. The features in each blurred image are counted and measured using SExtractor. The cumulative size distribution is found to be a power law in all passbands with a slope of about -1.5 over 1.8 orders of magnitudes. The luminosity distribution is approximately a power law too, with a slope of about -1 for logarithmic intervals of luminosity. The results suggest a scale-free nature for stellar aggregates in a galaxy disk. Fractal models of thin disks reproduce the projected size distribution and suggest a projected mass distribution slope of about -0.5 for these extended regions. This mass slope converts to the observed luminosity slope if we account for luminosity evolution and longer lifetimes in larger regions.
Chandar Rupali
Elmegreen Bruce G.
Elmegreen Debra Meloy
Regan Michael
Whitmore Brad
No associations
LandOfFree
Hierarchical Star Formation in the Spiral Galaxy NGC 628 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Hierarchical Star Formation in the Spiral Galaxy NGC 628, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hierarchical Star Formation in the Spiral Galaxy NGC 628 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-243863