RT Journal Article T1 XMM observation of the dynamically young galaxy cluster CL 0939+4713 A1 De Filippis, E. A1 Schindler, S. A1 Castillo Morales, María África AB We present an XMM observation of the distant galaxy cluster CL 0939+4713. The X-ray image shows pronounced substructure, with two main subclusters which have even some internal structure. This is an indication that the cluster is a dynamically young system. This conclusion is supported by the temperature distribution: a hot region is found between the two main subclusters indicating that they are at the beginning of a major merger, and that they will probably collide in a few hundreds of Myr. The intra-cluster gas of CL 0939+4713 shows inhomogeneities in the metal distribution, with the optically richer subcluster having a higher metallicity. PB EDP Sciencies SN 0004-6361 YR 2003 FD 2003-06 LK https://hdl.handle.net/20.500.14352/51407 UL https://hdl.handle.net/20.500.14352/51407 LA eng NO © ESO 2003. We are very grateful to Bernd Aschenbach for making the XMM data available to us. They are part of the TS/MPE guaranteed time. We thank L. M. Buson and M. Cappellari for kindly providing the HST image (grazie mille!). A. Castillo Morales acknowledges support by the Marie Curie Training Site grant HPMT-CT-2000-00136 by the European Commission. We also thank Dr. Phil A. James for carefully reading this paper. We also thank the referee Monique Arnaud: her suggestions and comments have greatly improved the reliability of the results obtained. NO Marie Curie Training Site grant, European Commission DS Docta Complutense RD 7 jul 2025