Deuterium and Oxygen toward Feige 110: Results from the FUSE Mission
Abstract
We present measurements of the column densities of interstellar D I and O I made with the Far Ultraviolet Spectroscopic Explorer (FUSE) and of H I made with the International Ultraviolet Explorer (IUE) toward the sdOB star Feige 110 [(l,b)=(74.09d,-59.07d) d=179+265-67 pc; z=-154+57-227 pc]. Our determination of the D I column density made use of curve-of-growth fitting and profile fitting analyses, while our O I column density determination used only curve-of-growth techniques. The H I column density was estimated by fitting the damping wings of the interstellar Lyα profile. We find logN(DI)=15.47+/-0.06, logN(OI)=16.73+/-0.10, and logN(HI)=20.14+0.13-0.20 (all errors 2 σ). This implies D/H=(2.14+/-0.82)×10-5, D/O=(5.50+1.64-1.33)×10-2, and O/H=(3.89+/-1.67)×10-4. Taken with the FUSE results reported in companion papers and previous measurements of the local interstellar medium (LISM), this suggests the possibility of spatial variability in D/H for sight lines exceeding ~100 pc. This result may constrain models which characterize the mixing timescales and length scales of material in the LISM.
- Publication:
-
The Astrophysical Journal Supplement Series
- Pub Date:
- May 2002
- DOI:
- 10.1086/339132
- arXiv:
- arXiv:astro-ph/0111332
- Bibcode:
- 2002ApJS..140...37F
- Keywords:
-
- Cosmology: Observations;
- ISM: Abundances;
- ISM: Clouds;
- Stars: Individual: Name: Feige 110;
- Ultraviolet: ISM;
- Astrophysics
- E-Print:
- 24 pages, 9 figures. Accepted for publication in the Astrophysical Journal Supplement Series. Replacement corrects a typo in original submission