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arXiv · 1406.4778

OGLE-SMC-LPV-00861 (LIN 9): the first proven Z And outburst in a Magellanic symbiotic star

Brent Miszalski·Joanna Mikołajewska·Andrzej Udalski
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Abstract

We report on the discovery of a new Small Magellanic Cloud (SMC) symbiotic star, OGLE-SMC-LPV-00861, previously catalogued as H$\alpha$ emission line source LIN 9. The OGLE light curve shows multiple-maxima outburst behaviour over $\sim$1200 d with a maximum outburst of $\Delta V=1.5$ mag. An optical spectrum of LIN 9 taken with the Southern African Large Telescope (SALT) at quiescence reveals a K5 red giant with emission lines confirming its symbiotic star nature, demonstrating the potential use of ongoing large time-domain surveys to identify strong symbiotic star candidates. It is the first Magellanic symbiotic star proven to show poorly understood Z And outbursts. At outburst the estimated hot component luminosity is $L\sim3165$ $L_\odot$, compared to $L\sim225$ $L_\odot$ at quiescence. Further observations are needed, especially at outburst, to better understand this unique Z And-like system at a known distance, and to provide essential input to physical models of the Z And phenomenon.

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Brent Miszalski, Joanna Mikołajewska, Andrzej Udalski. 2014-06-18. OGLE-SMC-LPV-00861 (LIN 9): the first proven Z And outburst in a Magellanic symbiotic star. https://doi.org/10.1093/mnrasl/slu098

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