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arXiv · 1210.6765

Period and period change measurements for 143 SuperWASP eclipsing binary candidates near the short-period limit and discovery of a doubly eclipsing quadruple system

M. E. Lohr·A. J. Norton·U. C. Kolb·P. F. L. Maxted·I. Todd·R. G. West
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Abstract

Building on previous work, a new search of the SuperWASP archive was carried out to identify eclipsing binary systems near the short-period limit. 143 candidate objects were detected with orbital periods between 16000 and 20000 s, of which 97 are new discoveries. Period changes significant at 1 sigma or more were detected in 74 of these objects, and in 38 the changes were significant at 3 sigma or more. The significant period changes observed followed an approximately normal distribution with a half-width at half-maximum of ~0.1 s/yr. There was no apparent relationship between period length and magnitude or direction of period change. Amongst several interesting individual objects studied, 1SWASP J093010.78+533859.5 is presented as a new doubly eclipsing quadruple system, consisting of a contact binary with a 19674.575 s period and an Algol-type binary with a 112799.109 s period, separated by 66.1 AU, being the sixth known system of this type.

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M. E. Lohr, A. J. Norton, U. C. Kolb, P. F. L. Maxted, I. Todd, R. G. West. 2012-10-25. Period and period change measurements for 143 SuperWASP eclipsing binary candidates near the short-period limit and discovery of a doubly eclipsing quadruple system. https://doi.org/10.1051/0004-6361/201220562

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