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

被引:16
作者
Bluhm, H [1 ]
de Boer, KS [1 ]
机构
[1] Univ Bonn, Sternwarte, D-53121 Bonn, Germany
关键词
galaxies : individual : large magellanic cloud; ISM : abundances; ISM : molecules; ultraviolet : ISM;
D O I
10.1051/0004-6361:20011302
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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 approximate to 13.9 and 13.0, 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 approximate to 3 x 10(-15) erg s(-1) cm(-3) at 1000 Angstrom. The 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.
引用
收藏
页码:82 / 89
页数:8
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