* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Post Info TOPIC: Galaxy quenching


L

Posts: 131433
Date:
Galaxy quenching
Permalink  
 


Title: Galaxy Zoo: The interplay of quenching mechanisms in the group environment
Author: R. J. Smethurst, C. J. Lintott, S. P. Bamford, R. E. Hart, S. J. Kruk, K. L. Masters, R. C. Nichol, B. D. Simmons

Does the environment of a galaxy directly influence the quenching history of a galaxy? Here we investigate the detailed morphological structures and star formation histories of a sample of SDSS group galaxies with both classifications from Galaxy Zoo 2 and NUV detections in GALEX. We use the optical and NUV colours to infer the quenching time and rate describing a simple exponentially declining SFH for each galaxy, along with a control sample of field galaxies. We find that the time since quenching and the rate of quenching do not correlate with the relative velocity of a satellite but are correlated with the group potential. This quenching occurs within an average quenching timescale of ~2.5 Gyr from star forming to complete quiescence, during an average infall time (from ~10R_200 to 0.01R_200) of ~2.6 Gyr. Our results suggest that the environment does play a direct role in galaxy quenching through quenching mechanisms which are correlated with the group potential, such as harassment, interactions or starvation. Environmental quenching mechanisms which are correlated with satellite velocity, such as ram pressure stripping, are not the main cause of quenching in the group environment. We find that no single mechanism dominates over another, except in the most extreme environments or masses. Instead an interplay of mergers, mass & morphological quenching and environment driven quenching mechanisms dependent on the group potential drive galaxy evolution in groups.

Read more (3104kb, PDF)



__________________
Page 1 of 1  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard