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We present a study of the core of the Fe Ka emission line at ~6.4 keV in asample of type II Seyfert galaxies observed by the Chandra High Energy Grating(HEG). The sample consists of 29 observations of 10 unique sources. We presentmeasurements of the Fe Ka line parameters with the highest spectral resolutioncurrently available. In particular, we derive the most robust intrinsic linewidths for some of the sources in the sample to date. We obtained a weightedmean FWHM of 2000 \pm 160 km/s for 8 out of 10 sources (the remaining sourceshad insufficient signal-to-noise). From a comparison with the opticalemission-line widths obtained from spectropolarimetric observations, we foundthat the location of Fe Ka line-emitting material is a factor of ~0.7-11 timesthe size of the optical BLR. Furthermore, compared to 13 type I AGNs for whichthe best Fe Ka line FWHM constraints were obtained, we found no difference inthe FWHM distribution or the mean FWHM, and this conclusion is independent ofthe central black hole mass. This result suggests that the bulk of the Fe Kaline emission may originate from a universal region at the same radius withrespect to the gravitational radius, ~30,000 Rg on average. By examining thecorrelation between the Fe Ka luminosity and the [O IV] line luminosity, wefound a marginal difference in the Fe K line flux between type I and type IIAGNs, but the spread in the ratio of L(Fe) to L([O IV]) is about two orders ofmagnitude. Our results confirm the theoretical expectation that the Fe Kaemission-line luminosity cannot trivially be used as a proxy of the intrinsicAGN luminosity, unless a detailed comparison of the data with proper models isapplied.

Chandra High Energy Grating Observations of the Fe Ka Line Core in Type 2 Seyfert Galaxies: A Comparison with Type 1 Nuclei