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The Infrared Counterpart of the X-ray Burster KS 1731--260

R. P. Mignani·S. Chaty·F. Mirabel·S. Mereghetti
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Abstract

We present JK' infrared images of the X-ray transient KS 1731--260, obtained in 1997 and in 1998 with IRAC2b at the ESO/MPI 2.2-m telescope at La Silla. Using as a reference the recent Chandra position, we confirm the identification of the X-ray source with the previously proposed counterpart (Wijnands et al. 2001b), for which we measure J=17.32 +/- 0.2 and K' = 16.36 +/- 0.18. The source was entering a low X-ray state at the epoch of our observations, and the accretion disk was still dominating the infrared flux. Indeed, when compared with the only published magnitudes in the J-band (Orosz et al. 2001), obtained with the source in quiescence, our photometry confirms the fading of the counterpart during the decay of the RXTE/ASM lightcurve.

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R. P. Mignani, S. Chaty, F. Mirabel, S. Mereghetti. 2002-05-06. The Infrared Counterpart of the X-ray Burster KS 1731--260. https://doi.org/10.1051/0004-6361%3A20020650

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