INTEGRAL observations of HER X-1

D. Klochkov; R. Staubert; S. Tsygankov; A. Lutovinov; K. P. Postnov; N. I. Shakura; S. A. Potanin; C. Ferrigno; I. Kreykenbohm; J. Wilms

arXiv · 0704.3062

INTEGRAL observations of HER X-1

D. Klochkov·R. Staubert·S. Tsygankov·A. Lutovinov·K. P. Postnov·N. I. Shakura·S. A. Potanin·C. Ferrigno·I. Kreykenbohm·J. Wilms

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Abstract

First results of observations of the low mass X-ray binary Her X-1/HZ Her performed by the INTEGRAL satellite in July-August 2005 are presented. A significant part of one 35 day main-on state was covered. The cyclotron line in the X-ray spectrum is well observed and its position and shape, as well as its variability with time and phase of the 1.24 s pulsation are explored. X-ray pulse profiles for different energy bands are studied throughout the observation. The pulse period is found to vary on short time scales revealing a dynamical spin-up/spin-down behavior. Results of simultaneous optical observations of HZ Her are also discussed.

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D. Klochkov, R. Staubert, S. Tsygankov, A. Lutovinov, K. P. Postnov, N. I. Shakura, S. A. Potanin, C. Ferrigno, I. Kreykenbohm, J. Wilms. 2007-04-23. INTEGRAL observations of HER X-1. https://arxiv.org/abs/0704.3062

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