Bibcode
DOI
Centurion, Miriam; Vladilo, Giovanni
Bibliographical reference
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 372, May 10, 1991, p. 494-504.
Advertised on:
5
1991
Journal
Citations
41
Refereed citations
40
Description
The present study of the local insterstellar medium toward the center of
Loop I analyzes optical and UV spectra of nearby stars within the l =
310-330 deg, b = 15-25 deg area. The analysis of the UV spectra reveals
a sudden gas-column density increase as a function of distance from 10
to the 18th to 10 to the 20th/sq cm, suggesting the presence of a wall
of gas 40 + or - 25 pc from the sun; this constrains the distance to the
boundary of the soft X-ray emitting cavity around the sun, or 'Local
Bubble', in the direction toward the Loop I center. At greater
distances, the approximately constant N(H I), in conjunction with the
lack of interstellar components in the optical spectra, are suggestive
of the presence of another low-density gas column which can be
identified with the Loop I Bubble.