Mathematics – Logic
Scientific paper
Jan 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010aas...21534101c&link_type=abstract
American Astronomical Society, AAS Meeting #215, #341.01; Bulletin of the American Astronomical Society, Vol. 42, p.446
Mathematics
Logic
Scientific paper
We present color-magnitude and morphological analysis of 54 low-redshift ultraluminous infrared galaxies, a subset of the IRAS 1Jy sample (Kim & Sanders, 1998) in the Sloan Digital Sky Survey (SDSS). The ULIRGs are both bright and blue, and they form a group in the color-magnitude diagram distinct from both the red sequence and the blue cloud formed by the SDSS galaxies: the majority (47, or 87%) have the colors typical of the blue cloud, and only 3 (6%) sources are located in the red sequence. Strikingly, while ULIRGs are popularly thought to be precursors to a QSO phasewe find few (4, or 6%) in the "green valley” where the majority of the X-ray and IR selected AGNs are found. Visual inspection of morphology is in strong support of previous studies and the general view of ULIRGs as major mergers of gas-rich disk galaxies. A detailed morphology analysis using Gini and M20 coefficients shows that slightly less than one half (42% in g band) of the ULIRGs are located in the merger region defined by morphology studies of local galaxies, while the remaining sources are located in the region of late-type and irregular galaxies. The heterogeneous distribution of ULIRGs in the G-M20 space is qualitatively consistent with the results found by numerical simulations of disk-disk mergers, and our study also shows that the measured morphological parameters are systematically affected by the signal-to-noise ratio and thus the merging galaxies can appear in various regions of the G-M20 parameter space. We briefly discuss the origins of the uncertainties and note that the morphology measurements should be implemented with caution for low physical resolution images. In our study we also compare the color-magnitude relation and the morphology of the low-redshift ULIRGs with z 1 ULIRGs observed by HST.
Chen Yuxi
Lowenthal James D.
Yun Min. S.
No associations
LandOfFree
Color-Magnitude Relation and Morphology of ULIRGs 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 Color-Magnitude Relation and Morphology of ULIRGs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color-Magnitude Relation and Morphology of ULIRGs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-962347