Reprocessed emission from warped accretion discs with application to X-rayiron line profiles

Fluorescent iron line profiles currently provide the best diagnostic for en gine geometries of active galactic nuclei (AGN). Here we construct a method for calculating the relativistic iron line profile from an arbitrarily war ped accretion disc, illuminated from above and below by hard X-ray sources. This substantially generalizes previous calculations of reprocessing by ac cretion discs by including non-axisymmetric effects. We include a relativis tic treatment of shadowing by ray-tracing photon paths along Schwarzschild geodesics, We apply this method to two classes of warped discs, and generat e a selection of resulting line profiles. New profile features include a ti me-varying line profile if the warp precesses about the disc, profile diffe rences between 'twisted' and 'twist-free' warps and the possibility of stee per red and softer blue fall-offs than for flat discs. We discuss some qual itative implications of the line profiles in the context of Type I and II S eyfert AGN and other sources.