ATOMIC CARBON IN THE HIGH-LATITUDE MOLECULAR CLOUD MBM-12

We report the first detection of neutral atomic carbon emission from a high-latitude cloud. [C I] 492 GHz emission was detected from seven ( CO)-C-13 cores in MBM 12, the nearest known molecular cloud (d = 65 pc ; b = -34-degrees). There is strong evidence that the lines of [C I] a nd CO are formed in the same regions of the cloud. The average C/CO co lumn density ratio is approximately 0.7, which is a factor of approxim ately 1.4-7 times higher than the same value measured toward dense Gal actic photodissociation regions. Recent chemical models of translucent clouds with I(UV) = 1 Habing field can account for this ratio. Due to the proximity of MBM 12, we have discovered evidence for density clum ps with sizes less than or similar to 2000 AU. The clumps contain H-2 masses of order the mass of Jupiter.