Abstract

Studying the processes that influence and regulate star formation is critical to understanding the growth and development of galaxies. Low-mass galaxies may be sensitive probes of these processes, but their faintness makes studying them difficult at higher redshift. Deep grism spectroscopy offers a way to do this through accurate redshift measurement and estimates of galaxy star formation through the detection of emission lines. In the Faint Infrared Grism Survey (FIGS), we identify 24 candidate galaxy overdensities and 208 Emission Line Galaxies (ELGs) with 0 < z < 2.0 in low-resolution 1D spectra obtained using Hubble’s WFC3/G102 grism. The ELGs have measured line fluxes down to 10^-17 ergs/cm2/s and continuum magnitudes down to AB(F105W) < 28. We identify Hα6563, [OIII]5007, and [OII]3727 Å strong line emitters, from which we estimate star formation rates and gas-phase metallicities. We observe a correlation between specific star formation rate and low gas-phase metallicity, and find little evidence that a galaxy’s line emission relates closely to overdensity. In the HALO7D survey, we describe ongoing work using Keck/DEIMOS spectroscopy of low-mass galaxies to characterize their metallicity, star formation burstiness, and other properties.