Dependence of star formation activity on stellar mass and environment from the Redshift One LDSS-3 Emission line Survey

作者：Li I H^*; Glazebrook Karl; Gilbank David; Balogh Michael; Bower Richard; Baldry Ivan; Davies Greg; Hau George; McCarthy Pat

来源：Monthly Notices of the Royal Astronomical Society, 2011, 411(3): 1869-1879.

DOI：10.1111/j.1365-2966.2010.17816.x

• galaxies: evolution
• galaxies: general
• galaxies: stellar content

Using the sample from the Redshift One LDSS-3 Emission line Survey (ROLES), we probe the dependence of star formation rate (SFR) and specific star formation rate (sSFR) as a function of stellar mass M-* and environment as defined by local galaxy density, in the Chandra Deep Field South field. Our spectroscopic sample consists of 312 galaxies with K-AB < 24, corresponding to stellar mass log(M-M-circle dot) > 8.5, and with [O (II)] derived SFR > 0.3M(circle dot) yr(-1), at 0.889 <= z <= 1.149. The results have been compared directly with the Sloan Digital Sky Survey Stripe 82 sample at 0.032 <= z <= 0.05. For star-forming galaxies, we confirm that there is little correlation between SFR and density at z similar to 0. However, for the lowest mass galaxies in our z similar to 1 sample, those with log(M-M-circle dot) < 10, we find that both the median SFR and sSFR increase significantly with increasing local density. The 'downsizing' trend for low-mass galaxies to be quenched progressively later in time appears to be more pronounced in moderately overdense environments. Overall we find that the evolution of star formation in galaxies is most strongly driven by their stellar mass, with local galaxy density playing a role that becomes increasingly important for lower mass galaxies.

• 出版日期2011-3