Molecular Hydrogen Emission from the Inner 400 Parsecs of the Galaxy II. The UV-Excited H_2

Abstract

We have observed near-IR H$_2$ line emission on large scales in the Galactic center. Paper I discussed our 400 pc long strip map and 50 pc map of the H_2 v=1-0 S(1) line. In this paper, we present observations of the higher vibrational lines, H_2 v=2-1 S(1) and v=3-2 S(3), at selected positions and conclude that strong far--UV radiations excites the H_2. We compare the H_2 v=1-0 S(1) emission to far-IR continuum emission and show that the ratio of these two quantities in the Galactic center equals the ratio seen in the starburst galaxies, M82 and NGC 253, and in ultraluminous infrared bright galaxies.

8 pages, 6 postscript figures, uses paspconf.sty. To appear in the 4th ESO/CTIO Workshop "The Galactic Center"