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arXiv · astro-ph/9806007

The CV period gap: still there

U. Kolb·A. R. King·H. Ritter
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Abstract

We consider a recently-proposed alternative explanation of the CV period gap in terms of a revised mass-radius relation for the lower main sequence. We show that no such thermal-equilibrium relation is likely to produce a true gap. Using population synthesis techniques we calculate a model population that obeys the claimed equilibrium mass-radius relation. A theoretical period histogram obtained from this population shows two prominent period spikes rather than a gap. We consider also recent arguments suggesting that the period gap itself may not be real. We argue that, far from demonstrating a weakness of the interrupted-braking picture, the fact that most CV subtypes prefer one side of the gap or the other is actually an expected consequence of it.

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U. Kolb, A. R. King, H. Ritter. 1998-05-31. The CV period gap: still there. https://arxiv.org/abs/astro-ph/9806007

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