McBride, V. A., Wilms, J. (Joern), Kreykenbohm, I., Coe, M. J. (Malcolm J.), Rothschild, Richard E., 1943-, Kretschmar, P., Pottschmidt, K., Fisher, J. and Hamson, T.. (2007) On the cyclotron line in Cepheus X-4. Astronomy & Astrophysics, Vol.470 (No.3). pp. 1065-1070. ISSN 0004-6361

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Abstract

Context. Accreting X-ray pulsars provide us with laboratories for the study of extreme gravitational and magnetic fields, hence accurate descriptions of their observational properties contribute to our understanding of this group of objects. Aims. We aim to detect a cyclotron resonance scattering feature in the Be/X-ray binary Cep X-4 and to investigate pulse profile and spectral changes through the outburst. Methods. Spectral fitting and timing analysis are employed to probe the properties of Cep X-4 during an outburst in 2002 June. Results. A previously announced cyclotron feature at 30.7 keV is confirmed, while the source shows spectral behaviour and luminosity related changes similar to those observed in previous outbursts. The long-term X-ray lightcurve shows a periodicity at 20.85 d, which could be attributed to the orbit in this Be system.

Item Type:	Journal Article
Subjects:	Q Science > QB Astronomy
Divisions:	Faculty of Science > Physics
Library of Congress Subject Headings (LCSH):	Pulsars, Stars -- Magnetic fields, X-ray binaries, X-ray sources, Galactic -- Accretion, Cyclotrons
Journal or Publication Title:	Astronomy & Astrophysics
Publisher:	EDP Sciences
ISSN:	0004-6361
Date:	August 2007
Volume:	Vol.470
Number:	No.3
Page Range:	pp. 1065-1070
Identification Number:	10.1051/0004-6361:20077238
Status:	Peer Reviewed
Access rights to Published version:	Open Access
Funder:	National Research Foundation (South Africa), British Council, University of Southampton
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URI:	http://wrap.warwick.ac.uk/id/eprint/3461

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