DISCOVERY OF A DWARF CARBON STAR WITH A WHITE-DWARF COMPANION AND OF A HIGHLY MAGNETIC DEGENERATE STAR

We report herein the discovery of two very unusual stars, identified d uring follow-up spectroscopy of candidates from the Second Byurakan Su rvey (SBS). SBS 1517+5017 is an object with a composite spectrum which we identify as a dwarf carbon star plus white dwarf binary-only the s econd such combination known. Since the system is unresolved spatially , we cannot yet determine whether the separation is small enough for m ass transfer to have occurred when the evolved component was an asympt otic giant. The second unusual object we examine is SBS 1349+5434, whi ch we show to be a magnetic white dwarf with an equivalent polar field strength among the strongest found among white dwarfs at 760 x 10(6) G. Given its immense field, the low measured polarization-both linear and circular-of this object is surprising and suggests that the field pattern over the stellar surface may be quite complex.