FUV/UV/Optical Observations of the symbiotic star AG Dra

Session 44 - Circumstellar Material.
Display session, Tuesday, January 16
North Banquet Hall, Convention Center

[44.09] FUV/UV/Optical Observations of the symbiotic star AG Dra

B. R. Espey (JHU/U. Pitt.), J. Birriel (U. Pitt.), R. E. Schulte-Ladbeck (U. Pitt.), J. J. Johnson (U. Wisconsin, Madison), H. M. Schmidt (MSSO), H. Schild (ETH Zürich)

We present spectroscopic data of AG Draconis covering the far-ultraviolet (FUV), ultraviolet (UV) and optical regions and obtained during the Astro-2 Space Shuttle astronomy mission in March 1995, approximately eight months after peak light of the system's most recent outburst. We have supplemented these data with UV -- FUV archival data obtained with the IUE\/ and ORFEUS\/ satellites. We discuss these data in the light of the strength of the nebular emission from this object, in particular from the higher excitation lines, and the physical conditions estimated from the emission line diagnostics. Additional information provided via.\/ the Raman-scattering of O\sc VI 1032, 1038 emission lines will also be discussed in comparison with recent results for the symbiotic nova RR Tel (Espey, B.R., et al. 1995, ApJ 454, L61).

Using the high resolution ORFEUS\/ data obtained during a Space Shuttle mission in the fall of 1993, combined with more recent UV and ground-based data, we discuss likely origins for the strong nebular emission features and the relative importance of the contributions of the winds from the hot star and the cool giant, and the shocked region between them.

This work is supported by NASA contract NAS 5-27000 to the Johns Hopkins University. and by Astro-2 Guest Investigator grants NAG 8-1049 and NAG 8-1073 to Espey and Schulte-Ladbeck, respectively.

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