Is HE 0436–4717 anemic? A deep look at a bare Seyfert 1 galaxy

Abstract

A multi-epoch, multi-instrument analysis of the Seyfert 1 galaxy HE 0436–4717 is conducted using optical to X-ray data from XMM–Newton and Swift (including the Burst Alert Telescope). Fitting of the UV-to-X-ray spectral energy distribution shows little evidence of extinction and the X-ray spectral analysis does not confirm previous reports of deep absorption edges from O VIII.HE 0436–4717 is a ‘bare’ Seyfert with negligible line-of-sight absorption making it ideal to study the central X-ray emitting region. Three scenarios were considered to describe the X-ray data: partial covering absorption, blurred reflection, and soft Comptonization. All three interpretations describe the 0.5–10.0 keV spectra well. Extrapolating the models to 100 keV results in poorer fits for the partial covering model.When also considering the rapid variability during one of the XMM–Newton observations, the blurred reflection model appears to describe all the observations in the most self-consistent manner. If adopted, the blurred reflection model requires a very low iron abundance in HE 0436–4717. We consider the possibilities that this is an artefact of the fitting process, but it appears possible that it is intrinsic to the object.