Evidence of thermal disequilibrium in contact binaries
نویسنده
چکیده
We present a test which is sufficient to disprove thermal equilibrium in observed contact binaries. The test is applied to a number of systems with good spectroscopic data. All of them are shown to be in thermal imbalance. Accordingly, many (possibly all) contact binaries evolve on a thermal time-scale, probably in thermal cycles as proposed by Lucy (1976) and Flannery (1976).
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