H-2, HD, and CO at the edge of 30 Dor in the LMC: The line of sight to Sk-69 246

Citation
H. Bluhm et Ks. De Boer, H-2, HD, and CO at the edge of 30 Dor in the LMC: The line of sight to Sk-69 246, ASTRON ASTR, 379(1), 2001, pp. 82-89
Citations number
34
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
14320746 → ACNP
Volume
379
Issue
1
Year of publication
2001
Pages
82 - 89
Database
ISI
SICI code
1432-0746(200111)379:1<82:HHACAT>2.0.ZU;2-I
Abstract
Fuse and IUE observations of Sk-69 246, a WN 6 star to the north of 30 Dor, reveal the existence of LMC interstellar gas in at least 3 velocity compon ents. In one of these components Fuse spectra show strong absorption by mol ecular hydrogen with a column density of log N(H-2) =19.6. We investigate t he physical conditions in this cloud, which is probably located near the H II region surrounding Sk-69 246. HD and CO with column densities of approxi mate to 13.9 and 13.0, respectively, are detected. The N(CO)-to-N(H-2) rati o is consistent with values found in the Galaxy. From the population of the rotational levels of H-2 we derive a gas temperature of 72 K and a radiati on field U approximate to 3 x 10(-15) erg s(-1) cm(-3) at 1000 Angstrom. Th e fractional abundance f = 2N(H-2)/[N(H I) +2N(H-2)] approximate to 0.07 is rather high for an E(B - V) less than or similar to 0.1.