Companions of post-common envelope sdB binaries

Elizabeth M. Green, Biqing For, Elaina A. Hyde, Ivo R. Seitenzahl, Keith Callerame, Brooke A. White, Corryn N. Young, Christopher S. Huff, Jay Mills, Justin D R Steinfadt

    Research output: Contribution to journalArticlepeer-review

    15 Citations (Scopus)


    Preliminary results are presented from two ongoing complementary surveys intended to investigate the nature and characteristics of the optically invisible secondaries in post-common envelope subdwarf B (sdB) binary stars. We obtain precise radial velocities to derive periods and minimum companion masses for bright field sdB stars. These data are combined with light curves to search for eclipses, reflection effects, or ellipsoidal variations. We emphasize the importance of using complete unbiased samples, without which it will not be possible to understand the details of the multiple processes that produce these stars. It remains true that all known secondary companions in short-period sdB binaries are nearly invisible, thus they must be either low mass main sequence (MS) stars or compact objects, e.g., white dwarfs. In our small, nearly-complete sample, white dwarf secondaries outnumber MS secondaries by about a factor of five. Known MS masses in short-period sdB binaries are all surprisingly low, indicating a possible bimodal mass distribution for all MS secondaries in sdB binaries.

    Original languageEnglish
    Pages (from-to)267-274
    Number of pages8
    JournalAstrophysics and Space Science
    Issue number3-4
    Publication statusPublished - 2004


    • binary stars
    • common envelope evolution
    • subdwarf B stars


    Dive into the research topics of 'Companions of post-common envelope sdB binaries'. Together they form a unique fingerprint.

    Cite this