SWS SPECTROSCOPY OF MOLECULAR HYDROGEN LINES IN BRIGHT IR GALAXIES

one of the most remarkable discoveries from our mpe guaranteedtime program is the existence of enormous amounts (m virgul 10^9 msun) of warm (t100200k) molecular hydrogen (h2) gases in bright ir galaxies. by observing a number of rovibrational h2 lines, we will determine whether the h2 is excited by uv radiation field or shocks. with this information in hand, we will further investigate the mechanism which is generating the large luminosities of these galaxies.