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Discovery and study of the accreting pulsar 2RXP J130159.6-635806

M. Chernyakova·A. Lutovinov·J. Rodriguez·M. Revnivtsev
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Abstract

We report on analysis of the poorly studied source 2RXP J130159.6-635806 at different epochs with ASCA, Beppo-SAX, XMM-Newton, and INTEGRAL. The source shows coherent X-ray pulsations at a period ~700s with an average spin up rate of about dnu/dt ~ 2x10^{-13} Hz/s. A broad band (1-60 keV) spectral analysis of 2RXP J130159.6-635806 based on almost simultaneous XMM-Newton and INTEGRAL data demonstrates that the source has a spectrum typical of an accretion powered X-ray pulsar, i.e. an absorbed power law with a high energy cut-off with a photon index Gamma ~ 0.5-1.0 and a cut-off energy of ~25 keV. The long term behaviour of the source, its spectral and timing properties, tend to indicate a high mass X-ray binary with Be companion. We also report on the identification of the likely infrared counterpart to 2RXP J130159.6-635806. The interstellar reddening does not allow us to strongly constrain the spectral type of the counterpart. The latter is, however, consistent with a Be star, the kind of which is often observed in accretion powered X-ray pulsars.

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M. Chernyakova, A. Lutovinov, J. Rodriguez, M. Revnivtsev. 2005-08-25. Discovery and study of the accreting pulsar 2RXP J130159.6-635806. https://doi.org/10.1111/j.1365-2966.2005.09548.x

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