Identification of 13 DB + dM and 2 DC + dM binaries from the Sloan Digital Sky Survey

Abstract

We present the identification of 13 DB + dM binaries and 2 DC + dM binaries from the Sloan Digital Sky Survey (SDSS). Before the SDSS only 2 DB + dM binaries and 1 DC + dM binary were known. At least three, possibly 8, of the new DB + dM binaries seem to have white dwarf temperatures well above 30 000 K which would place them in the so called