The origin of the Fe K features in Markarian 205 and Markarian 509

Abstract

We examine the 3-10 keV EPIC spectra of Mrk 205 and Mrk 509 to investigate their Fe K features. The most significant feature in the spectra of both objects is an emission line at 6.4 keV. The spectra can be adequately modelled with a power law and a relatively narrow (sigma < 0.2 keV) Fe K alpha emission line. Better fits are obtained when an additional Gaussian emission line, relativistic accretion-disk line, or Compton reflection from cold material, is added to the spectral model. We obtain similar goodness of fit for any of these three models, but the model including Compton reflection from cold material offers the simplest, physically self-consistent solution, because it only requires one reprocessing region. Thus the Fe K spectral features in Mrk 205 and Mrk 509 do not present strong evidence for reprocessing in the inner, relativistic parts of accretion disks.