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We have observed two low concentration Galactic globular clusters with theX-ray observatory XMM-Newton. We detect 47 faint X-ray sources in the directionof M 55 and 62 in the field of view of NGC 3201. Using the statistical LogN-Log S relationship of extragalactic sources derived from XMM-Newton LockmanHole observations, to estimate the background source population, we estimatethat very few of the sources (1.5+/-1.0) in the field of view of M 55 actuallybelong to the cluster. These sources are located in the centre of the clusteras we expect if the cluster has undergone mass segregation. NGC 3201 hasapproximately 15 related sources, which are centrally located but are notconstrained to lie within the half mass radius. The sources belonging to thiscluster can lie up to 5 core radii from the centre of the cluster which couldimply that this cluster has been perturbed. Using X-ray (and optical, in thecase of M 55) colours, spectral and timing analysis (where possible) andcomparing these observations to previous X-ray observations, we find evidencefor sources in each cluster that could be cataclysmic variables, activebinaries, millisecond pulsars and possible evidence for a quiescent low massX-ray binary with a neutron star primary, even though we do not expect any suchobjects in either of the clusters, due to their low central concentrations. Themajority of the other sources are background sources, such as AGN.Comment: 12 pages, 7 figures, accepted to be published in A&

XMM-Newton X-ray and optical observations of the globular clusters M 55 and NGC 3201