inflow_fig2

Although the accretion of gas onto galaxies is thought to play a key role in their formation and evolution, studies of cool gas kinematics in distant, star-forming galaxies have mostly reported the ubiquity of cool gas outflows.  In this work, we identify six star-forming galaxies drawn from a sample of ~100 objects (at 0.3 < z < 1.4) which show direct evidence for cool gas inflow.  We use spectroscopy of low-ionization metal absorption lines (MgII and FeII; see panels above) to measure gas kinematics, and identify inflows from the positive velocities of the metal absorption with respect to the host galaxies’ systemic velocities.  The Figure shows Hubble Space Telescope images (Giavalisco et al. 2004) of four of these inflow galaxies, along with their absorption-line spectra.  Please click here for the published article, and here to see our press release.