The Close Binary V342 Aquilae: A System Undergoing Extremely Active Mass Transfer
Session 47 -- Binary Stars
Display presentation, Thursday, June 15, 1995, 9:20am - 4:00pm

## [47.08] The Close Binary V342 Aquilae: A System Undergoing Extremely Active Mass Transfer

C.N.~Hartman (NASA/GSFC and CUA), R.S.~Polidan (NASA/GSFC), P.B.~Etzel (SDSU), F.C.~Bruhweiler (CUA)

Preliminary analysis of the eclipsing binary V342 Aquilae indicates it is undergoing an extremely active phase of mass transfer. This is seen in our comprehensive data set consisting of both IUE spectroscopic and photometric uvbyri data, providing complete orbital phase coverage of the 3.39 day period. IUE observations made in 1991, 1993 and 1995 include 65 low resolution SWP and LWP spectra providing spectral coverage from 1150 to 3200\AA. Besides variable H$\alpha$ emission seen in the optical, our UV spectra show very pronounced FeII absorption lines arising from ground and metastable levels, indicating an extensive circumstellar shell in the system. The strength of this absorption varies significantly over orbital phase. The eclipse spectra show very strong emission from lines such as CII at 1335\AA, Si IV at 1400\AA, and CIV at 1550\AA. The UV spectra clearly show that the primary is earlier than B8. The effective temperatures, spectral types and orbital geometry of the two stars, as well as the properties of the surrounding circumstellar envelope and the eclipse spectra will be discussed. Our ongoing analysis aims to understand the unusually large rate of mass flow occuring in V342 Aquilae.

P.B.E acknowledges support under NSF grant AST-9115104.