We studied the soft-X-ray emission of five hard-X sources : IGR J08262-3736 , IGR J17354-3255 , IGR J16328-4726 , SAX J1818.6-1703 and IGR J17348-2045 .
These sources are : a confirmed supergiant high mass X-ray binary ( IGR J08262-3736 ) ; candidates ( IGR J17354-3255 , IGR J16328-4726 ) and confirmed ( SAX J1818.6-1703 ) supergiant fast X-ray transients ; IGR J17348-2045 is one of the as-yet unidentified objects discovered with INTEGRAL . Thanks to dedicated XMM-Newton observations , we obtained the first detailed soft X-ray spectral and timing study of IGR J08262-3736 .
The results obtained from the observations of IGR J17354-3255 and IGR J16328-4726 provided further support in favor of their association with the class of Supergiant Fast X-ray Transients .
SAX J1818.6-1703 , observed close to phase 0.5 , was not detected by XMM-Newton , thus supporting the idea that this source reaches its lowest X-ray luminosity ( \sim 10 ^ { 32 } erg/s ) around apastron .
For IGR J17348-2045 we identified for the first time the soft X-ray counterpart and proposed the association with a close-by radio object , suggestive of an extragalactic origin .
In this proceeding we discuss the results obtained from the XMM-Newton follow-up observations of all the five sources .