AAS 202nd Meeting, May 2003
Session 32 Stellar Atmospheres and Circumstellar Material
Poster, Tuesday, May 27, 2003, 10:00am-6:30pm, West Exhbit Hall

## [32.03] Detection of a Raman Scattered He II Line in the Optical Spectrum of the Symbiotic Star V1016 Cyg

J. J. Birriel (Morehead State University)

Roughly half of all symbiotic stars exhibit two, strong broad Raman scattered emission lines at \lambda\lambda 6825 and 7082. These lines result from the inelastic scattering of O VI photons \lambda\lambda 1032 and 1038, respectively, on the ground state of neutral hydrogen. With the exception of a single planetary nebula, NGC 7027, Raman scattering has been observed only in the spectra of symbiotic stars. The young planetary nebula NGC 7027, which has two white dwarf central stars and has often been discussed as a possible post-symbiotic star, and the symbiotic star RR Tel each exhibit a broad, but weak emission feature blueward of H\alpha at \lambda 4850. This feature has been identified as a Raman scattered He II line produced by the scattering of He II photons of wavelength \lambda 972 the ground state of neutral hydrogen. We present evidence for a Raman scattered He II feature at \lambda 4850 in the spectrum of the symbiotic star V1016 Cyg. The scattering efficiency is calculated based on the observed strength of the He II \lambda 4686 line which is easily related to the strength of the far-UV He II line at \lambda 972.

Bulletin of the American Astronomical Society, 35 #3
© 2003. The American Astronomical Soceity.