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We present 6.4 keV iron K-alpha fluorescent line profiles predicted for arelativistic black hole accretion disk in the presence of a spiral motion inKerr geometry, the work extended from an earlier literature motivated by recentmagnetohydrodynamic (MHD) simulations. The velocity field of the spiral motion,superposed on the background Keplerian flow, results in a complicated redshiftdistribution in the accretion disk. An X-ray source attributed to a localizedflaring region on the black hole symmetry axis illuminates the iron in thedisk. The emissivity form becomes very steep because of the light bendingeffect from the primary X-ray source to the disk. The predicted line profile iscalculated for various spiral waves, and we found, regardless of the sourceheight, that: (i) a multiple-peak along with a classical double-peak structuregenerally appears, (ii) such a multiple-peak can be categorized into two types,sharp sub-peaks and periodic spiky peaks, (iii) a tightly-packed spiral wavetends to produce more spiky multiple peaks, whereas (iv) a spiral wave with alarger amplitude seems to generate more sharp sub-peaks, (v) the effect seemsto be less significant when the spiral wave is centrally concentrated, (vi) theline shape may show a drastic change (forming a double-peak, triple-peak ormultiple-peak feature) as the spiral wave rotates with the disk. Our resultsemphasize that around a rapidly-rotating black hole an extremely redshiftediron line profile with a noticeable spike-like feature can be realized in thepresence of the spiral wave. Future X-ray observations, from {\it Astro-E2} forexample, will have sufficient spectral resolution for testing our spiral wavemodel which exhibits unique spike-like features.Comment: 30 pages, 10 figures, submitted to ApJ, will be presented at 204th  Meeting of AAS in Denve

Iron Kα Fluorescent Line Profiles from Spiral Accretion Flows in Active Galactic Nuclei