INTEGRAL Observations of the Vela Region Focusing on Vela X-1

Stephane Schanne; Diego Gotz; Lucie Gerard; Patrick Sizun; Maurizio Falanga; Clarisse Hamadache; Bertand Cordier; Andreas von Kienlin

arXiv · astro-ph/0701641

INTEGRAL Observations of the Vela Region Focusing on Vela X-1

Stephane Schanne·Diego Gotz·Lucie Gerard·Patrick Sizun·Maurizio Falanga·Clarisse Hamadache·Bertand Cordier·Andreas von Kienlin

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Abstract

The Vela region has been observed for 1.7 Ms in November 2005 by the INTEGRAL satellite. We present preliminary spectral and temporal results of Vela X-1, an eclipsing neutron star hosted in a wind-accreting high-mass X-ray binary system. Using data from ISGRI, SPI and JEM-X, we firmly confirm the existence of cyclotron resonant scattering features (CRSF) at ~27 keV and ~54 keV, implying a neutron-star magnetic field of ~3 10^12 Gauss, and the presence of an iron emission line at ~6.5 keV. During two strong flares those parameters remained unchanged. Furthermore we measure the neutron-star spin period of 283.6 s, indicating a still constant trend.

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Stephane Schanne, Diego Gotz, Lucie Gerard, Patrick Sizun, Maurizio Falanga, Clarisse Hamadache, Bertand Cordier, Andreas von Kienlin. 2007-01-23. INTEGRAL Observations of the Vela Region Focusing on Vela X-1. https://arxiv.org/abs/astro-ph/0701641

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