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arXiv · astro-ph/0511601

3A 0535+262 in outburst

P. Kretschmar·K. Pottschmidt·C. Ferrigno·I. Kreykenbohm·A. Domingo·J. Wilms·R. Rothschild·W. Coburn·E. Kendziorra·R. Staubert·G. Schönherr·A. Santangelo·A. Segreto
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Abstract

The Be/X-ray binary 3A 0535+262 has the highest magnetic field determined by cyclotron line studies of all accreting X-ray pulsars, despite an open debate if the fundamental line was rather at ~50 or above 100 keV as observed by different instruments in past outbursts. The source went into quiescence for more than ten years since its last outbursts in 1994. Observing during a `normal' outburst August/September 2005 with Integral and RXTE we find a strong cyclotron line feature at ~45 keV and have for the first time since 1975 determined the low energy pulse profile.

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P. Kretschmar, K. Pottschmidt, C. Ferrigno, I. Kreykenbohm, A. Domingo, J. Wilms, R. Rothschild, W. Coburn, E. Kendziorra, R. Staubert, G. Schönherr, A. Santangelo, A. Segreto. 2005-11-21. 3A 0535+262 in outburst. https://arxiv.org/abs/astro-ph/0511601

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