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Optical photometry of the eclipsing Large Magellanic Cloud supersoft source CAL 87

C. Alcock
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Abstract

We present optical photometry of the eclipsing supersoft source, CAL87. These observations comprise long term data accumulated as a by-product of the MACHO Project, and high speed white light photometry of a single eclipse. We (i) derive an improved ephemeris of To = HJD 2450111.5144(3) + 0.44267714(6)E for the time of minimum light, (ii) find the eclipse structure to be stable over a period of 4 years, and (iii) investigate the colour variation as a function of orbital phase. The resolution afforded by the high speed nature of the white light observations enables us to see new structure in the light curve morphology.

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C. Alcock. 1997-02-13. Optical photometry of the eclipsing Large Magellanic Cloud supersoft source CAL 87. https://doi.org/10.1093/mnras%2F287.3.699

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