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In our previous work, using luminosity and the H-beta FWHM as surrogates forblack hole mass (M_BH), we compared the black hole masses of narrow-lineSeyfert 1 galaxies (NLS1s) and broad-line Seyfert 1 galaxies (BLS1s) in asample of soft X-ray-selected active galactic nuclei. We found that thedistributions of black hole masses in the two populations are statisticallydifferent. Recent work shows that the second moment of the H-beta emission line(the line dispersion) is a better estimator of black hole mass than FWHM. Totest whether changing the width measure affects our results, we calculate linedispersion-based black hole masses for our sample. We find that using the linedispersion rather than the FWHM as a measure of the gas velocity shifts NLS1and BLS1 virial product distributions closer together, but they remaindistinct. On the M_BH-sigma plane, we find that using the line dispersionleaves NLS1s below the M_BH-sigma relation, but to a less significant degreethan when FWHM is used to calculate black hole masses (the [OIII] 5007A FWHM isused as a surrogate for the bulge stellar velocity dispersion). The level ofsignificance of our findings is such that we cannot draw firm conclusions onthe location of the two samples on the M_BH-sigma plane. We are still left withtwo alternative scenarios: either (1) NLS1s lie below the M_BH-sigma relationindicating that their black hole masses are growing, or (2) NLS1s lie on theM_BH-sigma relation, so they preferentially reside in smaller mass, lessluminous galaxies; the present data do not allow us to choose one over theother. More trustworthy stellar velocity dispersions and accurate black holemass measurements are required for a firmer statement about the locus of NLS1son the M_BH-sigma plane.Comment: Accepted for publication in AJ; 9 pages, 4 figures, 1 tabl

Revisiting the Black Hole Masses of Soft X-Ray-Selected Active Galactic Nuclei