An analysis of the orbital periods of some eclipsing binaries suspected to be in the pre-main sequence contraction phase of evolution

作者: T. Panchatsaram , K. D. Abhyankar

DOI: 10.1007/BF02714240

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摘要: An analysis of the available photoelectric times minima KO Aql, TV Cas and Z Her, which are suspected to be in pre-main sequence phase evolution, reveals that Aql shows a secular increase its orbital period at rate 4.34 × 10 -8 day per cycle while has been decreasing 4·08 -9 cycle. Her does not show any change all. The binary system is will systematically affected because ' shrinking' dimensions com- ponents. A simple formula for characteristic change, defined by (P/P), derived from consideration conservation total energy angular momentum whose compo- nents still process contraction or expansion. applied above systems see whether theoretical charac- teristic changes agree with observed values. assumed evolve independently accordance model calculations Iben (1965). It found there no agreement between changes. This suggests may phase. We do have sufficient data judge evolutionary status present procedure; this also true TT Hya. suspect due light-time effect.

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