EUVE Science Highlights -
October 31, 1997
EUVE Science Highlights -
October 31, 1997
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Dr. Stephane Vennes (Space Sciences Lab., U.C. Berkeley and Astrophysical Theory Centre, Australian National University), Dr. Thomas Berghoefer (Space Sciences Laboratory, U.C. Berkeley) and Dr. Damian Christian (Center for EUV Astrophysics, U.C. Berkeley) announce the discovery of the presence of hot white dwarf(WD) companion to the B star HR 2875. This constitutes the first confirmed B star plus white dwarf system. An EUVE pointed observation (1996 April 5 - 14, 113 k sec) reveals a weak continuum spectrum in the short wavelength (SW) spectrometer characteristic of a hot WD. An analysis of the EUVE spectrum based on pure hydrogen model spectra confines the WD effective temperature between 34500-52000 K and the HI column density between 1.8-5.0 x 10^19 cm^-2. Vennes et al. discuss the likeliness this WD is more massive than average field white dwarfs (~0.6 solar mass). This is a consequence of the fact that the progenitor of this WD would have been a main sequence star earlier than B5 (mass greater of equal to 6 solar mass). Further study of this system are crucial to constrain the theoretical final-to-initial mass relation between WD and main sequence stars. More details about this discovery will soon be published in the Astrophysical Journal Letters.