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A look with BeppoSAX at the low-luminosity Galactic X-ray source 4U 2206+54

N. Masetti·D. Dal Fiume·L. Amati·S. Del Sordo·F. Frontera·M. Orlandini·E. Palazzi
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Abstract

A pointed observation of the low-luminosity galactic source 4U 2206+54 was carried out in November 1998 with BeppoSAX. The light curve of 4U 2206+54 shows erratic variability on a timescale of about 1 hour; neither hardness variations nor time periodicities are detected throughout this 67 ks long observation. Thanks to the wide spectral coverage capabilities of BeppoSAX we could observe the source X-ray continuum over three energy decades, from 0.6 to 60 keV. The spectrum could be equally well fitted either with a blackbody plus Comptonization or with a high energy cutoff power law. No iron emission around 6.5 keV was detected, while a tentative detection of a cyclotron resonant feature in absorption is presented. Comparison of the present BeppoSAX data with the information available in the literature for this source suggests that 4U 2206+54 is a close binary system in which a (possibly magnetized) NS is accreting from the companion star wind.

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N. Masetti, D. Dal Fiume, L. Amati, S. Del Sordo, F. Frontera, M. Orlandini, E. Palazzi. 2004-05-21. A look with BeppoSAX at the low-luminosity Galactic X-ray source 4U 2206+54. https://doi.org/10.1051/0004-6361%3A20040273

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