Evidence of thermal disequilibrium in contact binaries
Received 1 May 1996 / Accepted 3 July 1996
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).
Key words: stars binaries close
© European Southern Observatory (ESO) 1997
Online publication: July 8, 1998