The complex X-ray spectrum of the isolated neutron star RBS1223

Axel D. Schwope; Valeri Hambaryan; Frank Haberl; Christian Motch

doi:10.1007/s10509-007-9375-1

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The complex X-ray spectrum of the isolated neutron star RBS1223

Axel D. Schwope·Valeri Hambaryan·Frank Haberl·Christian Motch

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Abstract

We present a first analysis of a deep X-ray spectrum of the isolated neutron star RBS1223 obtained with XMM-Newton. Spectral data from four new monitoring observations in 2005/2006 were combined with archival observations obtained in 2003 and 2004 to form a spin-phase averaged spectrum containing 290000 EPIC-pn photons. This spectrum shows higher complexity than its predecessors, and can be parameterised with two Gaussian absorption lines superimposed on a blackbody. The line centers, E_2 ~ 2E_1, could be regarded as supporting the cyclotron interpretation of the absorption features in a field B ~ 4 x 10**13 G. The flux ratio of those lines does not support this interpretation. Hence, either feature might be of truly atomic origin.

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Axel D. Schwope, Valeri Hambaryan, Frank Haberl, Christian Motch. 2006-09-26. The complex X-ray spectrum of the isolated neutron star RBS1223. https://doi.org/10.1007/s10509-007-9375-1

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