Interstellar Carbon in Translucent Sightlines

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted for publication in the Astrophysical Journal

Scientific paper

10.1086/382592

We report interstellar C II column densities or upper limits determined from weak absorption of the 2325.4029 A intersystem transition observed in six translucent sightlines with STIS. The sightlines sample a wide range of interstellar characteristics including total-to-selective extinction, R_{V} = 2.6 - 5.1; average hydrogen density along the sightline, = 3 - 14 cm^{-3}; and fraction of H in molecular form, 0 - 40%. Four of the sightlines, those toward HD 37021, HD 37061, HD 147888 and HD 207198, have interstellar gas-phase abundances that are consistent with the diffuse sightline ratio of 161 +/- 17 carbon atoms in the gas per million hydrogen nuclei. We note that while it has a gas-phase carbon abundance that is consistent with the other sightlines, a large fraction of the C II toward HD 37061 is in an excited state. The sightline toward HD 152590 has a measured interstellar gas-phase carbon abundance that is well above the diffuse sightline average; the column density of C in this sightline may be overestimated due to noise structure in the data. Toward HD 27778 we find a 3 sigma abundance upper limit of <108 C atoms in the gas per million H, a substantially enhanced depletion of C as compared to the diffuse sightline value. The interstellar characteristics toward HD 27778 are otherwise not extreme among the sample except for an unusually large abundance of CO molecules in the gas.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Interstellar Carbon in Translucent Sightlines does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Interstellar Carbon in Translucent Sightlines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interstellar Carbon in Translucent Sightlines will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-454729

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.