We investigate the burstiness of star formation histories (SFHs) of galaxies
at $0.4<z<1$ by using the ratio of star formation rates (SFRs) measured from
FUV (1500 \AA) and H$\beta$ (FUV--to--H$\beta$ ratio). Our sample contains 164
galaxies down to stellar mass (M*) of $10^8.5 M_ødot$ in the CANDELS GOODS-N
region, where TKRS Keck/DEIMOS spectroscopy and HST/WFC3 F275W images from
CANDELS and HDUV are available. When the ratio of FUV- and H$\beta$-derived
SFRs is measured, dust extinction correction is negligible (except for very
dusty galaxies) with the Calzetti attenuation curve. The FUV--to--H$\beta$
ratio of our sample increases with the decrease of M* and SFR. The median ratio
is $\sim$1 at M* $10^10 M_ødot$ (or SFR = 20 $M_ødot$/yr) and
increases to $\sim$1.6 at M* $10^8.5 M_ødot$ (or SFR $0.5
M_ødot$/yr). At M* $< 10^9.5 M_ødot$, our median FUV--to--H$\beta$ ratio is
higher than that of local galaxies at the same M*, implying a redshift
evolution. Bursty SFH on a timescale of $\sim$10 Myr on galactic scales
provides a plausible explanation of our results, and the importance of the
burstiness increases as M* decreases. Due to sample selection effects, our
FUV--to--H$\beta$ ratio may be a lower limit of the true value of a complete
sample, which strengthens our conclusions. Other models, e.g., non-universal
initial mass function or stochastic star formation on star cluster scales, are
unable to plausibly explain our results.
Описание
[1604.05314] The Bursty Star Formation Histories of Low-mass Galaxies at $0.4<z<1$ Revealed by Star Formation Rates Measured from FUV and H$\beta$
%0 Generic
%1 guo2016bursty
%A Guo, Yicheng
%A Rafelski, Marc
%A Faber, S. M.
%A Koo, David C.
%A Krumholz, Mark R.
%A Trump, Jonathan R.
%A Willner, S. P.
%A Amorín, Ricardo
%A Barro, Guillermo
%A Bell, Eric F.
%A Gardner, Jonathan P.
%A Gawiser, Eric
%A Hathi, Nimish P.
%A Koekemoer, Anton M.
%A Pacifici, Camilla
%A Pérez-González, Pablo G.
%A Ravindranath, Swara
%A Reddy, Naveen
%A Teplitz, Harry I.
%A Yesuf, Hassen
%D 2016
%K bursty dwarfs sfr z~1
%T The Bursty Star Formation Histories of Low-mass Galaxies at $0.4<z<1$
Revealed by Star Formation Rates Measured from FUV and H$\beta$
%U http://arxiv.org/abs/1604.05314
%X We investigate the burstiness of star formation histories (SFHs) of galaxies
at $0.4<z<1$ by using the ratio of star formation rates (SFRs) measured from
FUV (1500 \AA) and H$\beta$ (FUV--to--H$\beta$ ratio). Our sample contains 164
galaxies down to stellar mass (M*) of $10^8.5 M_ødot$ in the CANDELS GOODS-N
region, where TKRS Keck/DEIMOS spectroscopy and HST/WFC3 F275W images from
CANDELS and HDUV are available. When the ratio of FUV- and H$\beta$-derived
SFRs is measured, dust extinction correction is negligible (except for very
dusty galaxies) with the Calzetti attenuation curve. The FUV--to--H$\beta$
ratio of our sample increases with the decrease of M* and SFR. The median ratio
is $\sim$1 at M* $10^10 M_ødot$ (or SFR = 20 $M_ødot$/yr) and
increases to $\sim$1.6 at M* $10^8.5 M_ødot$ (or SFR $0.5
M_ødot$/yr). At M* $< 10^9.5 M_ødot$, our median FUV--to--H$\beta$ ratio is
higher than that of local galaxies at the same M*, implying a redshift
evolution. Bursty SFH on a timescale of $\sim$10 Myr on galactic scales
provides a plausible explanation of our results, and the importance of the
burstiness increases as M* decreases. Due to sample selection effects, our
FUV--to--H$\beta$ ratio may be a lower limit of the true value of a complete
sample, which strengthens our conclusions. Other models, e.g., non-universal
initial mass function or stochastic star formation on star cluster scales, are
unable to plausibly explain our results.
@misc{guo2016bursty,
abstract = {We investigate the burstiness of star formation histories (SFHs) of galaxies
at $0.4<z<1$ by using the ratio of star formation rates (SFRs) measured from
FUV (1500 \AA) and H$\beta$ (FUV--to--H$\beta$ ratio). Our sample contains 164
galaxies down to stellar mass (M*) of $10^{8.5} M_\odot$ in the CANDELS GOODS-N
region, where TKRS Keck/DEIMOS spectroscopy and HST/WFC3 F275W images from
CANDELS and HDUV are available. When the ratio of FUV- and H$\beta$-derived
SFRs is measured, dust extinction correction is negligible (except for very
dusty galaxies) with the Calzetti attenuation curve. The FUV--to--H$\beta$
ratio of our sample increases with the decrease of M* and SFR. The median ratio
is $\sim$1 at M* $\sim 10^{10} M_\odot$ (or SFR = 20 $M_\odot$/yr) and
increases to $\sim$1.6 at M* $\sim 10^{8.5} M_\odot$ (or SFR $\sim 0.5
M_\odot$/yr). At M* $< 10^{9.5} M_\odot$, our median FUV--to--H$\beta$ ratio is
higher than that of local galaxies at the same M*, implying a redshift
evolution. Bursty SFH on a timescale of $\sim$10 Myr on galactic scales
provides a plausible explanation of our results, and the importance of the
burstiness increases as M* decreases. Due to sample selection effects, our
FUV--to--H$\beta$ ratio may be a lower limit of the true value of a complete
sample, which strengthens our conclusions. Other models, e.g., non-universal
initial mass function or stochastic star formation on star cluster scales, are
unable to plausibly explain our results.},
added-at = {2016-04-20T10:09:58.000+0200},
author = {Guo, Yicheng and Rafelski, Marc and Faber, S. M. and Koo, David C. and Krumholz, Mark R. and Trump, Jonathan R. and Willner, S. P. and Amorín, Ricardo and Barro, Guillermo and Bell, Eric F. and Gardner, Jonathan P. and Gawiser, Eric and Hathi, Nimish P. and Koekemoer, Anton M. and Pacifici, Camilla and Pérez-González, Pablo G. and Ravindranath, Swara and Reddy, Naveen and Teplitz, Harry I. and Yesuf, Hassen},
biburl = {https://www.bibsonomy.org/bibtex/27ac0db7c092411645f4ac722895b1b4c/miki},
description = {[1604.05314] The Bursty Star Formation Histories of Low-mass Galaxies at $0.4<z<1$ Revealed by Star Formation Rates Measured from FUV and H$\beta$},
interhash = {64fcdec676eeeb4fa7bfaa6852fdbd28},
intrahash = {7ac0db7c092411645f4ac722895b1b4c},
keywords = {bursty dwarfs sfr z~1},
note = {cite arxiv:1604.05314Comment: 10 pages, 7 figures. Submitted to ApJ. Comments welcome},
timestamp = {2016-04-20T10:09:58.000+0200},
title = {The Bursty Star Formation Histories of Low-mass Galaxies at $0.4<z<1$
Revealed by Star Formation Rates Measured from FUV and H$\beta$},
url = {http://arxiv.org/abs/1604.05314},
year = 2016
}