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INTEGRAL observations of V0332+53 in outburst

I. Kreykenbohm·N. Mowlavi·N. Produit·S. Soldi·R. Walter·P. Dubath·P. Lubinski·M. Tuerler·W. Coburn·A. Santangelo·R. E. Rothschild·R. Staubert
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Abstract

We present the analysis of a 100ksec Integral(3-100kev) observation of the transient X-ray pulsar V0332+53 inoutburst. The source is pulsating at P=4.3751+/-0.0002s with a clear double pulse from 6 kev to 60 kev. The average flux was ~550mCrab between 20 kev and 60 kev. We modeled the broad band continuum from 5 kev to 100 kev with a power-law modified by an exponential cut off. We observe three cyclotron lines: the fundamental line at 24.9+/-0.1 kev, the first harmonic at 50.5+/-0.1 kev as well as the second harmonic at71.7+/-0.8 kev, thus confirming the discovery of the harmonic lines by Coburn et al. (2005) in RXTE data.

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I. Kreykenbohm, N. Mowlavi, N. Produit, S. Soldi, R. Walter, P. Dubath, P. Lubinski, M. Tuerler, W. Coburn, A. Santangelo, R. E. Rothschild, R. Staubert. 2005-03-01. INTEGRAL observations of V0332+53 in outburst. https://doi.org/10.1051/0004-6361%3A200500023

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