04/29/02
Durret Florence	IAP
98bis Bd Arago	SF2A- PNC- PNG- ENS
75014	Paris, France

Presentation 1 : None
The extreme ultraviolet excess in five clusters of galaxies revisited
F. Durret, E. Slezak, R. Lieu, S. Dos Santos, M. Bonamente
Evidence for excess extreme ultraviolet (EUV) emission over a tail of X-ray gas bremsstrahlung emission has been building up recently, but in some cases remains controversial, mostly due to the moderate quality of the EUV data. In order to improve the signal to noise ratio in the EUV, we have performed the wavelet analysis and image reconstructions for five clusters of galaxies observed both at EUV and X-ray energies with the EUVE and ROSAT satellites respectively. The profiles of the EUV and X-ray reconstructed images all differ at a very large confidence level and an EUV excess over a thermal bremsstrahlung tail is detected in all five clusters (Abell 1795, Abell 2199, Abell 4059, Coma and Virgo). These results, coupled with recent XMM-Newton observations, suggest that the EUV excess is probably non thermal in origin.

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