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A Reanalysis of the Carbon Abundance in the Translucent Cloud toward HD 24534

Ulysses J. Sofia·Edward L. Fitzpatrick·David M. Meyer
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Abstract

We have reanalyzed the Goddard High Resolution Spectrograph data set presented by Snow et al. which contains the interstellar intersystem C II] 2325A line through the translucent cloud toward HD 24534 (X Persei). In contrast to the results of Snow et al., we clearly detect the C II] feature at the 3-sigma confidence level and measure a C^+ column density of 2.7 +/- 0.8 x 10^17 cm^-2. Accounting for the C I column density along the line of sight, we find 10^6 C/H = 106 +/- 38 in the interstellar gas toward this star. This gas-phase carbon-to-hydrogen ratio suggests that slightly more carbon depletion may be occurring in translucent as compared to diffuse clouds. The average diffuse-cloud C/H, however, is within the 1-sigma uncertainty of the measurement toward HD 24534. We therefore cannot rule out the possibility that the two cloud types have comparable gas-phase C/H, and therefore comparable depletions of carbon.

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Ulysses J. Sofia, Edward L. Fitzpatrick, David M. Meyer. 1998-06-30. A Reanalysis of the Carbon Abundance in the Translucent Cloud toward HD 24534. https://doi.org/10.1086/311566

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