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H2, HD, and CO at the edge of 30 Dor in the LMC: the line of sight to Sk-69 246

Hartmut Bluhm·Klaas S. de Boer
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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 components.In one of these components FUSE spectra show strong absorption by molecular hydrogen with a column density of log N(H_2)=19.6. We investigate the 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 about 13.9 and 13.0 dex, respectively, are detected. The N(CO)-to-N(H_2) ratio 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 radiation field U=3*10^-15 erg/(s*cm^3) at 1000 nm. The fractional abundance f=2N(H_2)/[N(H I)+2N(H_2)] is approximately 0.07, rather high for an E(B-V)<0.1.

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Hartmut Bluhm, Klaas S. de Boer. 2001-09-18. H2, HD, and CO at the edge of 30 Dor in the LMC: the line of sight to Sk-69 246. https://doi.org/10.1051/0004-6361%3A20011302

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