Halo Gas Velocities of NGC 4244 and NGC 891 Using Multi-long-slit Spectroscopy

Extra-planar gas in spiral galaxies can originate from disk-halo cycling driven by star formation in the disk or from infalling gas clouds. Studying the kinematics of halo gas can provide evidence for which scenario is more plausible. Edge-on galaxies provide a direct view of the extra-planar gas. We measure gas velocities from Hα emission as a function of height above the galactic disk for NGC 4244, which has a low star formation rate, and NGC 891, which has a high star formation rate. Using a multi-slit setup on the ARC 3.5 m telescope, we are able to measure velocities along 16 slits simultaneously. We compare our preliminary results to studies of HI velocities in these galaxies.