Jason X. Prochaska

UC Santa Cruz

Revealing the ISM of High z Galaxies with GRB Afterglows

I will discuss new insight on the physical conditions of the interstellar medium (ISM) of high redshift galaxies through absorption line spectroscopy of gamma-ray burst (GRB) afterglows. The analysis reveals the gas surface density, metallicity, molecular content, dust content, velocity field and distance from the GRB afterglow. These, in turn, constrain the nature of the progenitor star of long-duration GRBs and the properties of the gas fueling star formation in the early universe.