The origin of the strong soft excess and puzzling iron line complex in Mkn 841
Maraschi, L.; Nandra, K.; Ponti, G.; Boisson, C.; Malzac, J.; Henri, G.; Matt, G.; Petrucci, P. O.; Ferrando, P.; Mouchet, M.; Longinotti, A.
France, Italy, Spain, United Kingdom
Abstract
Mkn 841 has been observed during 3 different periods (January 2001, January 2005 and July 2005) by XMM-Newton for a total cumulated exposure time of ∼108 ks. We present in this paper a broad band spectral analysis of the complete EPIC-pn data sets. These observations confirm the presence of the strong soft excess and complex iron line profile known to be present in this source since a long time. They also reveal their extreme and puzzling spectral and temporal behaviors. Indeed, the 0.5-2 keV soft X-ray flux decreases by a factor 3 between 2001 and 2005 and the line shape appears to be a mixed of broad and narrow components, both variable but on different timescales. The broad-band 0.5-10 keV spectra are well described by a model including a primary power law continuum, a blurred photoionized reflection and a narrow iron line, the blurred reflection fitting self-consistently the soft excess and the broad line component. The origin and nature of the narrow component is unclear.