The relationship between galaxy star formation rates (SFR) and stellar masses
($M_\ast$) is re-examined using a mass-selected sample of $\sim$62,000
star-forming galaxies at $z 1.3$ in the COSMOS 2-deg$^2$ field. Using new
far-infrared photometry from $Herschel$-PACS and SPIRE and $Spitzer$-MIPS 24
$\mu$m, along with derived infrared luminosities from the NRK method based on
galaxies' locations in the restframe color-color diagram $(NUV - r)$ vs. $(r -
K)$, we are able to more accurately determine total SFRs for our complete
sample. At all redshifts, the relationship between median $SFR$ and $M_\ast$
follows a power-law at low stellar masses, and flattens to nearly constant SFR
at high stellar masses. We describe a new parameterization that provides the
best fit to the main sequence and characterizes the low mass power-law slope,
turnover mass, and overall scaling. The turnover in the main sequence occurs at
a characteristic mass of about $M_0 10^10 M_ødot$ at all redshifts.
The low mass power-law slope ranges from 0.9-1.3 and the overall scaling rises
in SFR as a function of $(1+z)^4.12 0.10$. A broken power-law fit below
and above the turnover mass gives relationships of $SFR M_*^0.88 \pm
0.06$ below the turnover mass and $SFR M_*^0.27 0.04$ above
the turnover mass. Galaxies more massive than $M_10^10\ M_\rm
ødot$ have on average, a much lower specific star formation rate (sSFR) than
would be expected by simply extrapolating the traditional linear fit to the
main sequence found for less massive galaxies.
Description
[1501.01080] A Turnover in the Galaxy Main Sequence of Star Formation at $M_{*} \sim 10^{10} M_{\odot}$ for Redshifts $z < 1.3$
%0 Generic
%1 lee2015turnover
%A Lee, Nicholas
%A Sanders, D. B.
%A Casey, Caitlin M.
%A Toft, Sune
%A Scoville, N. Z.
%A Hung, Chao-Ling
%A Floc'h, Emeric Le
%A Ilbert, Olivier
%A Zahid, H. Jabran
%A Aussel, Herve
%A Capak, Peter
%A Kartaltepe, Jeyhan S.
%A Kewley, Lisa J.
%A Li, Yanxia
%A Schawinski, Kevin
%A Sheth, Kartik
%A Xiao, Quanbao
%D 2015
%K mass sfr stellar
%T A Turnover in the Galaxy Main Sequence of Star Formation at $M_* \sim
10^10 M_ødot$ for Redshifts $z < 1.3$
%U http://arxiv.org/abs/1501.01080
%X The relationship between galaxy star formation rates (SFR) and stellar masses
($M_\ast$) is re-examined using a mass-selected sample of $\sim$62,000
star-forming galaxies at $z 1.3$ in the COSMOS 2-deg$^2$ field. Using new
far-infrared photometry from $Herschel$-PACS and SPIRE and $Spitzer$-MIPS 24
$\mu$m, along with derived infrared luminosities from the NRK method based on
galaxies' locations in the restframe color-color diagram $(NUV - r)$ vs. $(r -
K)$, we are able to more accurately determine total SFRs for our complete
sample. At all redshifts, the relationship between median $SFR$ and $M_\ast$
follows a power-law at low stellar masses, and flattens to nearly constant SFR
at high stellar masses. We describe a new parameterization that provides the
best fit to the main sequence and characterizes the low mass power-law slope,
turnover mass, and overall scaling. The turnover in the main sequence occurs at
a characteristic mass of about $M_0 10^10 M_ødot$ at all redshifts.
The low mass power-law slope ranges from 0.9-1.3 and the overall scaling rises
in SFR as a function of $(1+z)^4.12 0.10$. A broken power-law fit below
and above the turnover mass gives relationships of $SFR M_*^0.88 \pm
0.06$ below the turnover mass and $SFR M_*^0.27 0.04$ above
the turnover mass. Galaxies more massive than $M_10^10\ M_\rm
ødot$ have on average, a much lower specific star formation rate (sSFR) than
would be expected by simply extrapolating the traditional linear fit to the
main sequence found for less massive galaxies.
@misc{lee2015turnover,
abstract = {The relationship between galaxy star formation rates (SFR) and stellar masses
($M_\ast$) is re-examined using a mass-selected sample of $\sim$62,000
star-forming galaxies at $z \le 1.3$ in the COSMOS 2-deg$^2$ field. Using new
far-infrared photometry from $Herschel$-PACS and SPIRE and $Spitzer$-MIPS 24
$\mu$m, along with derived infrared luminosities from the NRK method based on
galaxies' locations in the restframe color-color diagram $(NUV - r)$ vs. $(r -
K)$, we are able to more accurately determine total SFRs for our complete
sample. At all redshifts, the relationship between median $SFR$ and $M_\ast$
follows a power-law at low stellar masses, and flattens to nearly constant SFR
at high stellar masses. We describe a new parameterization that provides the
best fit to the main sequence and characterizes the low mass power-law slope,
turnover mass, and overall scaling. The turnover in the main sequence occurs at
a characteristic mass of about $M_{0} \sim 10^{10} M_{\odot}$ at all redshifts.
The low mass power-law slope ranges from 0.9-1.3 and the overall scaling rises
in SFR as a function of $(1+z)^{4.12 \pm 0.10}$. A broken power-law fit below
and above the turnover mass gives relationships of $SFR \propto M_{*}^{0.88 \pm
0.06}$ below the turnover mass and $SFR \propto M_{*}^{0.27 \pm 0.04}$ above
the turnover mass. Galaxies more massive than $M_\ast \gtrsim 10^{10}\ M_{\rm
\odot}$ have on average, a much lower specific star formation rate (sSFR) than
would be expected by simply extrapolating the traditional linear fit to the
main sequence found for less massive galaxies.},
added-at = {2015-01-07T09:44:21.000+0100},
author = {Lee, Nicholas and Sanders, D. B. and Casey, Caitlin M. and Toft, Sune and Scoville, N. Z. and Hung, Chao-Ling and Floc'h, Emeric Le and Ilbert, Olivier and Zahid, H. Jabran and Aussel, Herve and Capak, Peter and Kartaltepe, Jeyhan S. and Kewley, Lisa J. and Li, Yanxia and Schawinski, Kevin and Sheth, Kartik and Xiao, Quanbao},
biburl = {https://www.bibsonomy.org/bibtex/21414ec6034e0310a34cffb7c45f9a7b1/miki},
description = {[1501.01080] A Turnover in the Galaxy Main Sequence of Star Formation at $M_{*} \sim 10^{10} M_{\odot}$ for Redshifts $z < 1.3$},
interhash = {354d6b8684f059b3141cd3e0b38adeb1},
intrahash = {1414ec6034e0310a34cffb7c45f9a7b1},
keywords = {mass sfr stellar},
note = {cite arxiv:1501.01080Comment: 16 pages, 7 figures. Accepted for publication in ApJ},
timestamp = {2015-01-07T09:44:21.000+0100},
title = {A Turnover in the Galaxy Main Sequence of Star Formation at $M_{*} \sim
10^{10} M_{\odot}$ for Redshifts $z < 1.3$},
url = {http://arxiv.org/abs/1501.01080},
year = 2015
}