The Black Hole Mass-Stellar Velocity Dispersion Relationship For Quasars In The Sloan Digital Sky Survey Data Release 7

Salviander, Sarah
Shields, Gregory A.
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We assess evolution in the M-BH-sigma() relationship for quasars in the Sloan Digital Sky Survey Data Release 7 for the redshift range 0.1 < z < 1.2. We estimate the black hole mass, M-BH, using the "photoionization method," with the broad H beta or Mg II emission line and the quasar continuum luminosity. For the stellar velocity dispersion, we use the narrow [O III] or [O II] emission line as a surrogate. This study is a follow-up to an earlier study in which we investigated evolution in the M-BH-sigma() relationship in quasars from Data Release 3. The greatly increased number of quasars in our new sample has allowed us to break our lower-redshift subsample into black hole mass bins and probe the M-BH-sigma() relationship for constant black hole mass. The M-BH-sigma() relationship for the highest-mass (M-BH > 10(9.0) M-circle dot) and lowest-mass (M-BH < 10(7.5) M-circle dot) black holes appears to evolve significantly; however, most or all of this apparent evolution can be accounted for by various observational biases due to intrinsic scatter in the relationship and to uncertainties in observed quantities. The M-BH-sigma() relationship for black holes in the middle mass range (10(7.5) < M-BH < 10(9.0) M-circle dot) shows minimal change with redshift. The overall results suggest a limit of +/-0.2 dex on any evolution in the M-BH-sigma() relationship for quasars out to z approximate to 1 compared with the relationship observed in the local universe. Intrinsic scatter may also provide a plausible way to reconcile the wide range of results of several different studies of the black hole-galaxy relationships.

Salviander, Sarah, and Gregory A. Shields. "The black hole mass-stellar velocity dispersion relationship for quasars in the sloan digital sky survey data release 7." The Astrophysical Journal, Vol. 764, No. 1 (Feb., 2013): 80.