We present results on the SFR-$M_*$ relation (i.e., the "main sequence")
among star-forming galaxies at $1.37z łeq2.61$ using the MOSFIRE Deep
Evolution Field (MOSDEF) survey. Based on a sample of 261 star-forming galaxies
with observations of H$\alpha$ and H$\beta$ emission lines, we have estimated
robust dust-corrected instantaneous star-formation rates (SFRs) over a large
dynamic range in stellar mass ($10^9.0-10^11.5M_ødot$). We find a
tight correlation between SFR(H$\alpha$) and $M_*$ with an intrinsic scatter of
0.36 dex, 0.05 dex larger than that of UV-based SFRs. This increased scatter is
consistent with predictions from numerical simulations of 0.03 - 0.1 dex, and
is attributed to H$\alpha$ more accurately tracing SFR variations. The slope of
the $łog(SFR)-łog(M_*)$ relation, using SFR(H$\alpha$), at $1.4<
z<2.6$ and over the stellar mass range of $10^9.5$ to $10^11.5M_ødot$ is
$0.650.09$. We find that different assumptions for the dust correction,
such as using the stellar $E(B-V)$ with a Calzetti et al. (2000) attenuation
curve, as well as the sample biases against red and dusty star-forming galaxies
at large masses, could yield steeper slopes. Moreover, not correcting the
Balmer emission line fluxes for the underlying Balmer absorption results in
overestimating the dust extinction of H$\alpha$ and SFR(H$\alpha$) at the
high-mass end by 2.1 (2.5) at $10^10.6 M_ødot$ ($10^11.1 M_ødot$) and
artificially increases the slope of the main-sequence. The shallower
main-sequence slope found here compared to that of galaxy evolution simulations
may be indicative of different feedback processes governing the low- and/or
high-mass end of the main sequence.
Description
[1507.03017] The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass relation using H$\alpha$ and H$\beta$ emission lines at z ~ 2
%0 Generic
%1 shivaei2015mosdef
%A Shivaei, Irene
%A Reddy, Naveen A.
%A Shapley, Alice E.
%A Kriek, Mariska
%A Siana, Brian
%A Mobasher, Bahram
%A Coil, Alison L.
%A Freeman, William R.
%A Sanders, Ryan
%A Price, Sedona H.
%A de Groot, Laura
%A Azadi, Mojegan
%D 2015
%K Halpha dust highz observations sfr
%T The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass
relation using H$\alpha$ and H$\beta$ emission lines at z ~ 2
%U http://arxiv.org/abs/1507.03017
%X We present results on the SFR-$M_*$ relation (i.e., the "main sequence")
among star-forming galaxies at $1.37z łeq2.61$ using the MOSFIRE Deep
Evolution Field (MOSDEF) survey. Based on a sample of 261 star-forming galaxies
with observations of H$\alpha$ and H$\beta$ emission lines, we have estimated
robust dust-corrected instantaneous star-formation rates (SFRs) over a large
dynamic range in stellar mass ($10^9.0-10^11.5M_ødot$). We find a
tight correlation between SFR(H$\alpha$) and $M_*$ with an intrinsic scatter of
0.36 dex, 0.05 dex larger than that of UV-based SFRs. This increased scatter is
consistent with predictions from numerical simulations of 0.03 - 0.1 dex, and
is attributed to H$\alpha$ more accurately tracing SFR variations. The slope of
the $łog(SFR)-łog(M_*)$ relation, using SFR(H$\alpha$), at $1.4<
z<2.6$ and over the stellar mass range of $10^9.5$ to $10^11.5M_ødot$ is
$0.650.09$. We find that different assumptions for the dust correction,
such as using the stellar $E(B-V)$ with a Calzetti et al. (2000) attenuation
curve, as well as the sample biases against red and dusty star-forming galaxies
at large masses, could yield steeper slopes. Moreover, not correcting the
Balmer emission line fluxes for the underlying Balmer absorption results in
overestimating the dust extinction of H$\alpha$ and SFR(H$\alpha$) at the
high-mass end by 2.1 (2.5) at $10^10.6 M_ødot$ ($10^11.1 M_ødot$) and
artificially increases the slope of the main-sequence. The shallower
main-sequence slope found here compared to that of galaxy evolution simulations
may be indicative of different feedback processes governing the low- and/or
high-mass end of the main sequence.
@misc{shivaei2015mosdef,
abstract = {We present results on the SFR-$M_*$ relation (i.e., the "main sequence")
among star-forming galaxies at $1.37\leq z \leq2.61$ using the MOSFIRE Deep
Evolution Field (MOSDEF) survey. Based on a sample of 261 star-forming galaxies
with observations of H$\alpha$ and H$\beta$ emission lines, we have estimated
robust dust-corrected instantaneous star-formation rates (SFRs) over a large
dynamic range in stellar mass ($\sim 10^{9.0}-10^{11.5}M_\odot$). We find a
tight correlation between SFR(H$\alpha$) and $M_*$ with an intrinsic scatter of
0.36 dex, 0.05 dex larger than that of UV-based SFRs. This increased scatter is
consistent with predictions from numerical simulations of 0.03 - 0.1 dex, and
is attributed to H$\alpha$ more accurately tracing SFR variations. The slope of
the $\log(\text{SFR})-\log(M_*)$ relation, using SFR(H$\alpha$), at $1.4<
z<2.6$ and over the stellar mass range of $10^{9.5}$ to $10^{11.5}M_\odot$ is
$0.65\pm 0.09$. We find that different assumptions for the dust correction,
such as using the stellar $E(B-V)$ with a Calzetti et al. (2000) attenuation
curve, as well as the sample biases against red and dusty star-forming galaxies
at large masses, could yield steeper slopes. Moreover, not correcting the
Balmer emission line fluxes for the underlying Balmer absorption results in
overestimating the dust extinction of H$\alpha$ and SFR(H$\alpha$) at the
high-mass end by 2.1 (2.5) at $10^{10.6} M_\odot$ ($10^{11.1} M_\odot$) and
artificially increases the slope of the main-sequence. The shallower
main-sequence slope found here compared to that of galaxy evolution simulations
may be indicative of different feedback processes governing the low- and/or
high-mass end of the main sequence.},
added-at = {2015-07-14T10:01:17.000+0200},
author = {Shivaei, Irene and Reddy, Naveen A. and Shapley, Alice E. and Kriek, Mariska and Siana, Brian and Mobasher, Bahram and Coil, Alison L. and Freeman, William R. and Sanders, Ryan and Price, Sedona H. and de Groot, Laura and Azadi, Mojegan},
biburl = {https://www.bibsonomy.org/bibtex/2fcbcb58b0e88e512a9bf192967c889e7/miki},
description = {[1507.03017] The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass relation using H$\alpha$ and H$\beta$ emission lines at z ~ 2},
interhash = {7ae889a0d1c620f8b05ad42870b59c7d},
intrahash = {fcbcb58b0e88e512a9bf192967c889e7},
keywords = {Halpha dust highz observations sfr},
note = {cite arxiv:1507.03017Comment: 12 pages, 8 figures, 2 tables, submitted to ApJ},
timestamp = {2015-07-14T10:01:17.000+0200},
title = {The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass
relation using H$\alpha$ and H$\beta$ emission lines at z ~ 2},
url = {http://arxiv.org/abs/1507.03017},
year = 2015
}