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NGC 5033 is an intriguing Seyfert galaxy because its sub-classification maychange with time, and because optical and sub-mm observations find that themassive black hole does not sit at the dynamical center of the galaxy, pointingto a past merger. We obtained a new optical spectrum of NGC 5033 using the200'' Hale telescope at Palomar that clearly reveals a broad H$\beta$ line(FWHM$=5400\pm 300~{\rm km}~{\rm s}^{-1}$). This signals a clear view of theoptical broad line region (BLR) and requires Seyfert-1.5 designation. Somespectra obtained in the past suggest a Seyfert-1.9 classification, potentiallysignaling a variable or "changing-look" geometry. Our analysis of a 2019Chandra spectrum of the massive black hole reveals very little obscuration,also suggesting a clean view of the central engine. However, the narrowFe~K$\alpha$ emission line is measured to have an equivalent with ofEW$=460^{+100}_{-90}$~eV. This value is extremely high compared to typicalvalues in unobscured AGN. Indeed, the line is persistently strong in NGC 5033:the line equivalent width in a 2002 XMM-Newton snapshot isEW$=250^{+40}_{-40}$~eV, similar to the EW$=290^{+100}_{-100}$~eV equivalentwidth measured using ASCA in 1999. These results can likely be explainedthrough a combination of an unusually high covering factor for reflection, andfluxes that are seen out of phase owing to light travel times. We examine thepossibility that NGC 5033 may strengthen evidence for the X-ray Baldwin effect.

Extreme X-ray Reflection in the Nucleus of the Seyfert Galaxy NGC 5033