090337

Ultra soft Narrow Line Seyfert 1 are characterized by a large spectral variability a very steep X-ray primary continuum ( and amp amp amp gt 2.5) and a strong soft excess. This remarkable spectral shape questions the origin of their broad-band UV-X-ray continuum compared to standard Seyfert galaxies. We propose to perform a monitoring composed of 5 x 26 ks XMM observations (total: 130 ks) spaced by 2-3 days and coordinated with HST to probe the FUV of RX J1355.2+5612. The proposed monitoring will allow us to 1) disentangle the different spectral components present from the UV/FUV to X-ray energy range and 2) investigate the nature of the soft X-ray excess and discriminate between the theoretical models that have been heavily discussed in the past decade [truncated! Please see actual data for full text]