%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 $0.4&lt;z&lt;1$ 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 }