We present here the analysis of X-rays point sources detected in several observations available in the XMM-Newton public archive .
We focused , in particular , on energies below 1 keV , which are of particular relevance to the understanding of the Diffuse X-ray Background .
The average field of all the exposures is 0.09 \textrm { deg } ^ { -2 } .
We reached an average flux sensitivity of 5.8 \times 10 ^ { -16 } ~ { } \textrm { erg~ { } s } ^ { -1 } ~ { } \textrm { cm } ^ { -2 } in the soft band ( 0.5-2.0 keV ) and 2.5 \times 10 ^ { -16 } ~ { } \textrm { erg~ { } s } ^ { -1 } ~ { } \textrm { cm } ^ { -2 } in the very soft band ( 0.4-0.6 keV ) .
In this paper we discuss the logN-logS results , the contribution to the integrated X-ray sky flux , and the properties of the cumulative spectrum from all sources .
In particular , we found an excess flux at around 0.5 keV in the composite spectrum of faint sources .
The excess seems to be a general property of all the fields observed suggesting an additional class of weak sources is contributing to the X-ray emission at these energies .
Combining our results with previous investigations we have also quantified the contribution of the individual components of the diffuse X-ray Background in the 3/4 keV band .