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arXiv · astro-ph/9907306

The isolated neutron star candidate RX J1605.3+3249

C. Motch·F. Haberl·F. -J. Zickgraf·G. Hasinger·A. D. Schwope
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Abstract

We report on X-ray and optical observations of a ROSAT X-ray source, RX J1605.3+3249, selected from the all-sky survey on the basis of its spectral softness and lack of bright optical counterpart. The ROSAT PSPC energy distribution is well fitted by a blackbody with kT = 92 +/- 6 eV and Nh =1.1 +/- 0.4 x 10^20 cm^-2. X-ray observations spanning 6.5 years fail to reveal any flux or spectral variability on any time scales. The ROSAT HRI error circle only contains a R = 23.25 M star which is unlikely to be associated with the X-ray source. We conclude that RX J1605.3+3249 is a probable nearby isolated neutron star detected from its thermal emission. The present data do not allow to unambiguously determine the X-ray powering mechanism, cooling from a young neutron star or heating by accretion from the interstellar medium onto an old neutron star. However, the long term stability of the X-ray flux favours the young neutron star hypothesis.

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C. Motch, F. Haberl, F. -J. Zickgraf, G. Hasinger, A. D. Schwope. 1999-07-22. The isolated neutron star candidate RX J1605.3+3249. https://arxiv.org/abs/astro-ph/9907306

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