Laboratory Simulations of Molecular Hydrogen Formation in the Early Universe: A Progress Report

During the epoch of protogalaxy and first star formation, H/sub 2/ is the main coolant of primordial gas for temperatures below ~8,000 K. The H/sub 2/ is formed via associative detachment (AD) of H/sup -/ and H. Uncertainties in the rate coefficient for this reaction have limited our understanding of protogalaxy formation during this epoch and of the characteristic masses and cooling times for the first stars. Recently we have carried out a series of laboratory measurements which remove these uncertainties. Here, we present the cosmological motivation for our work, describe the experimental approach, and point the reader to the relevant works where our AD results are reported and their cosmological implications explored.Anglai