X-Shooting EF Eridani: further evidence for a massive white dwarf and a sub-stellar secondary
Schwope, A.~D. and Christensen, L.
Keywords
stars: individual: EF Eridani, novae, cataclysmic variables
Abstract
High resolution spectral observations of the polar EF Eridani obtained in a low state with X-Shooter revealed narrow emission lines from the irradiated secondary. The lines were most prominent in the near-IR Ca2-triplet, the more intensive Halpha line had additional emission likely originating from an accretion stream. The lines with a radial velocity amplitude, K2_s14 = 385 _s16- 4 kmps, serve as tracer of the otherwise unseen companion. The mass function implies a massive white dwarf with Mwd > 0.65 Msun at 3sigma confidence, and a short distance to the binary, d ~ 111 pc (
