| Description: | Neutral atomic hydrogen (HI) is the primary fuel for star formation, and thus a critical component of galaxies. Understanding the evolution of HI in galaxies is thus important in understanding galaxy evolution. Unfortunately, little is known about the HI content of galaxies at even moderate redshifts,z>~0.3, due to the weakness of the HI 21cm line. For large galaxy samples, ``stacking'' of the redshifted HI 21cm emission allows us to achieve a far better HI mass sensitivity for the population than would be possible for individual objects.
In this talk, I will describe our recent results from such HI 21cm stacking experiments, using upgraded Giant Metrewave Radio Telescope HI 21cm spectroscopy of the DEEP2 Survey fields to probe the atomic gas mass of star-forming galaxies out to z~1.5. |
