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arXiv · 0709.4373

The pre-cataclysmic variable, LTT560

C. Tappert·B. T. Gaensicke·L. Schmidtobreick·A. Aungwerojwit·R. E. Mennickent·D. Koester
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Abstract

System parameters of the object LTT560 are determined in order to clarify its nature and evolutionary status. We apply time-series photometry to reveal orbital modulations of the light curve, time-series spectroscopy to measure radial velocities of features from both the primary and the secondary star, and flux-calibrated spectroscopy to derive temperatures of both components. We find that LTT560 is composed of a low temperature T~7500K DA white dwarf as the primary and an M5.5+-1 main-sequence star as the secondary component. The current orbital period is Porb=3.54(07)h. We derive a mass ratio Msec/Mwd = 0.36(03) and estimate the distance to d=25-40pc. Long-term variation of the orbital light curve and an additional H-alpha emission component on the white dwarf indicate activity in the system, probably in the form of flaring and/or accretion events.

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C. Tappert, B. T. Gaensicke, L. Schmidtobreick, A. Aungwerojwit, R. E. Mennickent, D. Koester. 2007-09-27. The pre-cataclysmic variable, LTT560. https://doi.org/10.1051/0004-6361:20077316

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