SIMBAD references

Using different kinds of velocity tracers derived from the broad Hβ 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 (σ_*), 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 Hβ line dispersion in the mean spectrum (σ_Hβ,mean_) has the smallest offset rms with respect to the M_BH–σ_* relation. For the total sample excluding SDSS-RM AGNs, with respect to M_BH from σ_* or that from the Hβ line dispersion in the rms spectrum (σ_Hβ,rms_), it is found that we can obtain M_BH from the σ_Hβ,mean_ with the smallest offset rms of 0.38 or 0.23 dex, respectively. It implies that, with respect to the Hβ FWHM, we prefer σ_Hβ,mean_ to calculate M_BH from the single-epoch spectrum. Using the FWHM-based f, we can improve the M_BH calculation from FWHM(Hβ) and the mean f, with a decreased offset rms from 0.52 to 0.39 dex with respect to M_BH from σ_* for the subsample of 36 AGNs with σ_*. The value of 0.39 dex is almost the same as that from σ_Hβ,mean_ and the mean f.