2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/178415We report the progress on our analysis of two deep XMM observations in the areas of Hubble Deep Field-North and the Groth-Westphal Strip field. We present the source detection method, Monte-Carlo simulation on source detection, and our preliminary Log N -- Log S relations. Comparing these two fields and other fields in literature, we find up to 30% variations in number counts near our flux limits, which is most likely to be due to cosmic variance. This serves as a pilot study for a more systematic investigation. The nature of the X-ray sources in the Groth-Westphal field is also discussed in terms of hardness ratios, morphology and spectroscopic properties.Replaced Fig. 3 which had an incorrect data point. Astron. Nachr. issue dedicated to the proceedings of the workshop "X-ray Surveys in the light of New Observatories", Sep. 2002, Santander, SpainAstrophysicstext