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Hard Spectra of X-Ray Pulsars from INTEGRAL Data

E. V. Filippova·S. S. Tsygankov·A. A. Lutovinov·R. A. Sunyaev
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Abstract

We present spectra for 34 accretion-powered X-ray and one millisecond pulsars that were within the field of view of the INTEGRAL observatory over two years (December 2002 - January 2005) of its in-orbit operation and that were detected by its instruments at a statistically significant level (> 8 sigma in the energy range 18--60 keV). There are seven recently discovered objects of this class among the pulsars studied: 2RXP J130159.6-635806, IGR/AX J16320-4751, IGR J16358-4726, AX J163904-4642, IGR J16465-4507, SAX/IGR J18027-2017 and AX J1841.0-0535. We have also obtained hard X-ray (> 20 keV) spectra for the accretion-powered pulsars A 0114+650, RX J0146.9+6121, AX J1820.5-1434, AX J1841.0-0535 and the millisecond pulsar XTE J1807-294 for the first time. We analyze the evolution of spectral parameters as a function of the intensity of the sources and compare these with the results of previous studies.

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E. V. Filippova, S. S. Tsygankov, A. A. Lutovinov, R. A. Sunyaev. 2005-09-18. Hard Spectra of X-Ray Pulsars from INTEGRAL Data. https://doi.org/10.1134/1.2123288

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