Exploring the Origin of the soft X-ray Excess in Mrk 926 Using Broadband X-ray Observations

The soft excess represents one of the only major remaining uncertainties in AGN spectral modeling in the X-ray band. Despite much effort, its nature is still a matter of active debate with some convinced it is caused by blurred ionized reflection and others by a warm corona above the accretion disk. We present results from a spectral analysis of an XMM/NuSTAR campaign of the unobscured Seyfert 1 galaxy Mrk 926. These results indicate that Mrk 926’s soft excess cannot be modelled adequately by either of the two currently favored explanations: it requires both. Based on our modeling results, we discuss what the detection of such a hybrid soft excess could mean for the broader AGN population, and what constraints can be placed on theoretical soft excess modelling.