We investigate the star-formation rate (SFR) and stellar mass (M∗) relation of a star-forming (SF) galaxy sample in the XMM-LSS field to z∼3.0 using the near-infrared data from the VISTA Deep Extragalactic Observations (VIDEO) survey. Combining VIDEO with broad-band photometry, we use the SED fitting algorithm CIGALE to derive SFRs and M∗ and have adapted it to account for the full photometric redshift PDF uncertainty. Applying a SF selection using the D4000 index, we find evidence for strong evolution in the normalisation of the SFR-M∗ relation out to z∼3 and a roughly constant slope of (SFR ∝M∗α) α=0.69±0.02 to z∼1.7. We find this increases close to unity toward z∼2.65. Alternatively, if we apply a colour selection, we find a distinct turnover in the SFR-M∗ relation between 0.7≲z≲2.0 at the high mass end, and suggest that this is due to an increased contamination from passive galaxies. We find evolution of the specific SFR ∝(1+z)2.60 at log(M∗)∼10.5, out to z≲2.4 with an observed flattening beyond z∼ 2 with increased stellar mass. Comparing to a range of simulations we find the analytical scaling relation approaches, that invoke an equilibrium model, a good fit to our data, suggesting that a continual smooth accretion regulated by continual outflows may be a key driver in the overall growth of SFGs.
@article{arxiv.1507.07503,
title = {The evolving relation between star-formation rate and stellar mass in the VIDEO Survey since $z=3$},
author = {Russell Johnston and Mattia Vaccari and Matt Jarvis and Mathew Smith and Elodie Giovannoli and Boris Häußler and Matthew Prescott},
journal= {arXiv preprint arXiv:1507.07503},
year = {2015}
}
Comments
19 pages, 18 figures, accepted for publication in MNRAS