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Description
Using different kinds of velocity tracers derived from the broad H{beta} profile (in the mean or rms spectrum) and the corresponding virial factors f, the central supermassive black hole masses (M_BH_) are calculated for a compiled sample of 120 reverberation-mapped (RM) active galactic nuclei (AGNs). For its subsample of RM AGNs with measured stellar velocity dispersion ({sigma}_*_), the multivariate linear regression technique is used to calibrate the mean value f, as well as the variable FWHM-based f. It is found that, whether excluding the pseudobulges or not, the M_BH_ from the H{beta} line dispersion in the mean spectrum ({sigma}_H{beta},mean_) has the smallest offset rms with respect to the M_BH_-{sigma}_*_ relation. For the total sample excluding SDSS-RM AGNs, with respect to M_BH_ from {sigma}_*_ or that from the H{beta} line dispersion in the rms spectrum ({sigma}_H{beta},rms_), it is found that we can obtain M_BH_ from the {sigma}_H{beta},mean_ with the smallest offset rms of 0.38 or 0.23dex, respectively. It implies that, with respect to the H{beta} FWHM, we prefer {sigma}_H{beta},mean_ to calculate M_BH_ from the single-epoch spectrum. Using the FWHM-based f, we can improve the M_BH_ calculation from FWHM(H{beta}) and the mean f, with a decreased offset rms from 0.52 to 0.39 dex with respect to M_BH_ from {sigma}_*_ for the subsample of 36 AGNs with {sigma}_*_. The value of 0.39dex is almost the same as that from {sigma}_H{beta},mean_ and the mean f.
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