Abstract We report the preliminary results of a 350 ks BeppoSAX observation of the bright atoll source GX 9+1. In the field of view of the MECS instrument we discovered a X-ray pulsar, designated SAX J1802.7-2017, at an angular distance from GX 9+1 of ∼ 22′. Since the X-ray emission of SAX J1802.7-2017 contaminates the energy spectrum above 10 keV we studied the energy spectrum of GX 9+1 in the energy band 0.1-10keV. We selected four regions in the color-color diagram and extracted one spectrum from each region. A bump below 1keV is present in the spectra using a model composed by a Comptonized component absorbed by neutral matter having an equivalent hydrogen column of 1.5 x 1022cm-2. The bump disappears adding an overabundance of iron and nickel of 7 and 70 with respect to the solar iron abundance and to the solar nickel abundance, moreover the equivalent hydrogen column becames 0.5 x 1022 cm-2 suggesting a possible distance to the source of 4.5 kpc, implying a luminosity of 4 x 1037ergs-1 and that the bright atoll source GX 9+1 is not bright but it is a typical atoll source.

Keywords accretion discs - stars: individual: GX 9+1 -- stars: neutron stars -- X-ray: stars -- X-ray: spectrum -- X-ray: general

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