SIMULTANEOUS X-RAY, UV, AND OPTICAL OBSERVATIONS OF THE RECENT NOVA HR DEL.

HR Del was observed simultaneously with the IUE satellite (low-dispersion spectroscopy), the DAO 1.8-m telescope (medium-dispersion spectroscopy), and the Einstein observatory (X-ray imaging proportional counter) over part or all of one 4-hour orbital cycle. The orbital ephemeris is refined and accurate phases computed for the data. The UV spectra show changes in the C IV P Cygni profile which suggest a spiralling stellar wind. A considerable overabundance of C and N in the wind is indicated. The UV data are also used to determine the continuum flux and temperature, and its variability. Optical spectroscopy shows some small changes since 1978 and confirms the strength of C features in the accretion disk. The X-ray observations yield a marginal detection, indicating a luminosity of 2 x 10 to the 31st erg/sec in the 0.5-3 keV flux. New estimates of the reddening and luminosity are derived.