INTEGRAL observation of the high-mass X-ray transient V 0332+53 during the 2005 outburst decline
Mowlavi, N., Kreykenbohm, I., Shaw, S. E. (Simon E.), Pottschmidt, K., Wilms, J. (Joern), Rodriguez, J. (Jerome), Produit, N., Soldi, S., Larsson, S. (Stefan) and Dubath, P.. (2006) INTEGRAL observation of the high-mass X-ray transient V 0332+53 during the 2005 outburst decline. Astronomy & Astrophysics, Vol.451 (No.1). pp. 187-194. ISSN 0004-6361
WRAP_Wilms_77_INTEGRAL_observation.pdf - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Official URL: http://dx.doi.org/10.1051/0004-6361:20054235
The decline of the high mass X-ray transient V 0332+53 during the Dec. 2004 to Feb. 2005 outburst is analysed from the data recorded by INTEGRAL. The flux is shown to decrease exponentially until 2005 Feb. 10, with a decay time scale of ∼30 days above 20 keV and ∼20 days at lower energies, and to decrease linearly thereafter.
The energy spectrum is well modelled throughout the decay by a power law with a folding energy of ∼7.5 keV, and with two cyclotron absorption features. The folding energy does not vary significantly over the decay, but the spectrum becomes harder with time. Most importantly, we show that the parameters describing the fundamental cyclotron line around 27 keV do vary with time: its energy and depth increase (by about 17% for the energy in ∼6 weeks), while its width decreases. These changes of the cyclotron line parameters are interpreted as resulting from a change in the extent of the cyclotron scattering region.
Two quasi-periodic oscillations are also observed at various times during the observations, one at 0.05 Hz and another one near the pulsation frequency around 0.23 Hz.
|Item Type:||Journal Article|
|Subjects:||Q Science > QB Astronomy|
|Divisions:||Faculty of Science > Physics|
|Library of Congress Subject Headings (LCSH):||X-ray sources, Galactic, Stars -- Magnetic fields, Pulsars|
|Journal or Publication Title:||Astronomy & Astrophysics|
|Official Date:||May 2006|
|Page Range:||pp. 187-194|
|Access rights to Published version:||Open Access|
Coburn, W., Kretschmar, P., Kreykenbohm, I., et al. 2005, ATel, 381,
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