David A. Wake, Pieter G. van Dokkum, Marijn Franx
Using data of nearby galaxies from the Sloan Digital Sky Survey we
investigate whether stellar mass, central velocity dispersion, surface mass
density, or the Sersic n parameter is best correlated with a galaxy's
rest-frame color. Specifically, we determine how the mean color of galaxies
varies with one parameter when another is fixed. When the stellar mass is fixed
we see that strong trends remain with all other parameters, whereas residual
trends are weaker when surface mass density, n, or velocity dispersion are
fixed. Overall velocity dispersion is the best indicator of a galaxy's typical
color, showing the largest residual color dependence when any of the other
three parameters are fixed, and stellar mass is the poorest. Other studies have
indicated that both the halo and black hole properties are better correlated
with velocity dispersion than with stellar mass, surface mass density or Sersic
n. Therefore, our results are consistent with a picture where a galaxy's star
formation history and present star formation rate are determined to some
significant degree by the current properties and assembly history of its dark
matter halo and/or the feedback from its central super massive black hole.
View original:
http://arxiv.org/abs/1201.4998
No comments:
Post a Comment