Ultraviolet Observations toward HD 135485: Searching for Evidence of a Proposed High Velocity Cloud
Session 35 -- ISM: Abundances and Dust
Display presentation, Wednesday, June 14, 1995, 9:20am - 6:30pm

## [35.07] Ultraviolet Observations toward HD 135485: Searching for Evidence of a Proposed High Velocity Cloud

L. Danly, Y.P. Lee (ST ScI), C.E. Albert (US Naval Academy)

Optical absorption line studies of the star HD 135485 (Albert et al. 1993) revealed several distinct absorption components at Ca II ($\lambda 3933 \AA$) at high velocities ($|v|>100$ km/s). If these features arise from interstellar clouds, similar features should be observable in other species commonly found in the interstellar medium. Ultraviolet spectra toward HD 135485 were obtained to confirm the presence of these absorption features in other spectral lines. Interestingly, the strong resonance lines of C II ($\lambda 1335 \AA$), Si II ($\lambda 1526 \AA, \lambda 1260 \AA$), O I ($\lambda 1302 \AA$) and Mg II ($\lambda \lambda 2796,2802 \AA$) do not show evidence for absorption at the high velocities indicated by the optical data. We conclude that the features observed near Ca II ($\lambda 3933 \AA$) are not interstellar. Indeed, the IUE ultraviolet spectra of HD 135485 reveal a complex pattern of stellar absorption, in keeping with its classification as a B5IIp star.