A SURVEY OF THE LARGE MAGELLANIC CLOUD IN THE [C II] 158 MICRON LINE

We have mapped the Large Magellanic Cloud (the LMC) in the [C II] 158 mum fine-structure line with the Balloon-borne Infrared Carbon Explore r (BICE) system. The [C II] line emission was detected over most of th e LMC. The mean [C II]/CO (J = 1-0) line intensity ratio was 23,000, 1 8 times larger than the typical value observed in the Galactic plane ( 1300). This result implies that each clump of the molecular clouds in the LMC has a larger C+ envelope relative to its CO core than those in our Galaxy. Lower dust abundance due to its lower metallicity allows UV photons, which convert CO molecules into C+ ions, to penetrate deep er into the clumps in the LMC than in our Galaxy.