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arXiv · 1008.4312

MML 53: a new low-mass, pre-main sequence eclipsing binary in the Upper Centarus-Lupus Region discovered by SuperWASP

L. Hebb·H. C. Stempels·S. Aigrain·A. Collier-Cameron·S. T. Hodgkin·J. M. Irwin·P. F. L. Maxted·D. Pollacco·R. A. Street·D. M. Wilson·K. G. Stassun
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Abstract

We announce the discovery of a new low-mass, pre-main sequence eclipsing binary, MML 53. Previous observations of MML 53 found it to be a pre-main sequence spectroscopic multiple associated with the 15-22 Myr Upper Centaurus Lupus cluster. We identify the object as an eclipsing binary for the first time through the analysis of multiple seasons of time series photometry from the SuperWASP transiting planet survey. Re-analysis of a single archive spectrum shows MML 53 to be a spatially unresolved triple system of young stars which all exhibit significant lithium absorption. Two of the components comprise an eclipsing binary with period, P = 2.097891(6) +- 0.000005 and mass ratio, q~0.8. Here, we present the analysis of the discovery data.

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L. Hebb, H. C. Stempels, S. Aigrain, A. Collier-Cameron, S. T. Hodgkin, J. M. Irwin, P. F. L. Maxted, D. Pollacco, R. A. Street, D. M. Wilson, K. G. Stassun. 2010-08-25. MML 53: a new low-mass, pre-main sequence eclipsing binary in the Upper Centarus-Lupus Region discovered by SuperWASP. https://doi.org/10.1051/0004-6361%2F201014059

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