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Recovery of the X-Ray Transient QX Nor (=X1608-52) in Outburst and Quiescence

Stefanie Wachter
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Abstract

We present optical and near-IR observations of QX Nor, the counterpart to the recurrent soft X-ray transient X1608-52, after its reappearance following the X-ray outburst in February 1996. The object has been seen only once before, during an X-ray outburst in 1977. Data from 3-5 months after the outburst show the counterpart at a mean magnitude of R=20.2 and variable on timescales of days. A comparison with identical observations in 1995 implies that the object has brightened by at least 1.8 mag in R following the X-ray outburst. We also detected QX Nor in the IR in both quiescence and outburst. A faint source is visible in the J but not the R band in May 1995. These first observations in the quiescent state yield magnitudes and colors consistent with optical emission from a low mass companion in the binary system, as is true in other soft X-ray transients.

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Stefanie Wachter. 1997-04-02. Recovery of the X-Ray Transient QX Nor (=X1608-52) in Outburst and Quiescence. https://doi.org/10.1086/304463

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