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تسجيل مستخدم جديدPost-common envelope binaries from SDSS-X: The origin of low-mass white dwarfs
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We present the first white dwarf mass distributions of a large and homogeneous sample of post-common envelope binaries (PCEBs) and wide white dwarf-main sequence binaries (WDMS) directly obtained from observations. Both distributions are statistically independent, with PCEBs showing a clear concentration of systems towards the low-mass end of the distribution, and the white dwarf mass distribution of wide WDMS binaries being similar to those of single white dwarfs. Our results provide evidence that the majority of low-mass (Mwd < 0.5Msun) white dwarfs are formed in close binaries.
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Context. An important ingredient in binary evolution is the common-envelope (CE) phase. Although this phase is believed to be responsible for the formation of many close binaries, the process is not well understood. Aims. We investigate the character
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We present a catalogue containing 839 candidate post common envelope systems. Common envelope evolution is very important in stellar astrophysics, particularly in the context of very compact and short-period binaries, including cataclysmic variables,
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