Program: GN-2006B-SV-110

In addition to its obvious importance in understanding black hole demographics and galaxy dynamics, the correlation between central black hole mass and stellar bulge velocity dispersion (the "M-sigma relationship") is of practical importance as a secondary method of estimating black hole masses. In the case of active galactic nuclei (AGNs), recent work on the M-sigma relationship suggests that reverberation-mapping methods, which are the most effective direct way to measure the masses of black holes in AGNs, may somewhat underestimate the black hole masses on account of inclination effects. Further investigation of this requires more velocity dispersion measurements of reverberation-mapped AGNs, an effort that has been frustrated by our inability to observe the Ca II triplet in QSOs with z > 0.06. However, with large telescopes with IFU and AO, it is possible to make velocity dispersion measurements using CO in the near IR. Here we propose to obtain during the NIFS SV program a single observation of one PG quasar to measure the velocity dispersion from the CO bandhead. We have a rather noisy spectrum obtained with VLT + ISAAC from which we were able to measure a velocity dispersion that is surprisingly high compared to the reverberation-based mass and the higher-quality spectrum we expect to obtain from NIFS will verify or negate this unexpected result, demonstrate the suitability of NIFS for obtain spectra of the host-galaxies of bright AGNs, and help us refine our technical approach to this effort based on actual NIFS data.