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Optical variability of the LMC supersoft source RX~J0513.9-6951 from MACHO Project photometry

C. Alcock et al
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Abstract

Using the exceptional monitoring capabilities of the MACHO project we present here the optical history of the LMC supersoft source (SSS) RX~J0513.9-6951, for a continuous 3 year period. Recurring low states, in which the optical brightness drops by up to a magnitude, are observed at quasi-regular intervals. This provides a crucial insight into the nature of the SSS and, in particular, a chance to investigate the poorly understood behaviour of their accretion discs. Analysis of the high state data reveals a small modulation of semi-amplitude $\sim$~0.02 mag at $P=$0.76278$\pm$0.00005~d, a period which is consistent with the current ``best'' suggested spectroscopic value.

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C. Alcock et al. 1996-05-15. Optical variability of the LMC supersoft source RX~J0513.9-6951 from MACHO Project photometry. https://doi.org/10.1093/mnras%2F280.3.l49

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