Péridier Library Abstract Archive

Abstract No. UT 364

Title: Lines of Circumstellar C₂, CN, and CH⁺ In the Optical Spectra of Post-AGB Stars
Author(s): Eric J. Bakker, David L. Lambert, Ewine F. Van Dishoeck
Keywords: circumstellar molecules, post-AGB stars, line profiles
E-Mail: Eric J. Bakker (to request a full copy of this paper)
Preprint: 9609030 Document source or PostScript
Release date: 09/27/96 14:30:46
Publication status: accepted to appear in IAU 177, "The Carbon Star Phenomenon"
Comments: 7 pages, 3 figures

Recent optical spectra of post-AGB stars show the presence of C₂, CN, and CH⁺ originating in the circumstellar shell. We present here new, higher resolution spectra which provide constraints on the physical para\-meters and information on the line profiles. An empirical curve of growth for the C₂ Phillips and CN Red system lines in the spectrum of HD 56126 yields b = 0.50^+0.59_-0.23 km s^-1. CH⁺ (0,0) emission lines in the spectrum of the Red Rectangle have been resolved with a FWHM approx 8.5 ± 0.8 km s^-1. The circumstellar CN lines of IRAS 08005-2356 are resolved into two separate components with a velocity separation of Delta v = 5.7 ± 2.0 km s^-1. The line profiles of CN of HD 235858 have not been resolved.