Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2011-05-12
2011, ApJ, 737, 41
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
10 pages, 4 figures, 2 tables, accepted for publication by ApJ
Scientific paper
Gas loss is thought to be important in SF quenching and morphological transition during the evolution of S0 galaxies. In high density environments, gas loss can be achieved via many external mechanisms. However, in relatively isolated environments, where these external mechanisms cannot be efficient, gas loss must be dominated by some internal processes. We perform Chandra analysis of hot gas in five nearby isolated S0 galaxies, based on quantitative subtraction of various stellar contributions. We find that all the galaxies studied in the present work are X-ray faint, with the hot gas luminosity LX<5% of the expected Ia SN energy injection rate. We further compare our results with those from relevant recent papers, in order to investigate the energy budget, cold-hot gas relation, and gas removal from S0 galaxies in isolated environments. We find that elliptical and S0 galaxies are not significantly different in LX at the low mass end (typically with LK<1e11Lsun). However, at the high mass end, S0 galaxies tend to have significantly lower LX than elliptical galaxies of the same stellar masses. We further discuss the potential relation of the diffuse X-ray emission with the cold gas content in S0 and elliptical galaxies. We find that LX/LK^2 tends to correlate positively with the total cold gas mass M(H2+HI) for gas-poor galaxies with M(H2+HI)<1e8Msun, while they anti-correlate with each other for gas-rich ones. This cold-hot gas relation can be explained in a scenario of galaxy evolution, with the leftover cold gas from the precursor star forming galaxy mainly removed by the long-lasting Ia SN feedback. The two different trends for gas-rich and -poor galaxies may be the results of the initial fast decreasing SN rate and the later fast decreasing mass-loading to hot gas, respectively.
Chen Yang
Li Jiang-Tao
Li Zhiyuan
Wang Daniel Q.
No associations
LandOfFree
Dynamic S0 Galaxies II: the Role of Diffuse Hot Gas 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 Dynamic S0 Galaxies II: the Role of Diffuse Hot Gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamic S0 Galaxies II: the Role of Diffuse Hot Gas will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-26558