Program: GN-2013B-Q-5

Title:A Stellar Dynamical Black Hole Mass for the Reverberation-Mapped Active Galaxy NGC6814
PI:Misty Bentz
Co-I(s): Christopher A. Onken, Monica Valluri, Emily Manne-Nicholas

Abstract

We propose to obtain spatially-resolved spectroscopy of the nucleus of the nearby (z=0.005) AGN NGC 6814 with Gemini NIFS+ALTAIR to model the gravitational influence of the central supermassive black hole on the stellar dynamics of the inner galaxy. A recent reverberation-based black hole mass of 2.0 x 10^7 M_sun for NGC 6814 places the black hole sphere of influence within the spatial resolution range of current ground-based AO systems. Because of the differing technical limitations of dynamical mass modeling and reverberation mapping, NGC 6814 is only the third galaxy where it is currently possible to directly compare a reverberation and a dynamical mass. Such a direct comparison provides an independent constraint on the geometric scaling factor that is currently the largest uncertainty in reverberation-based masses. All AGN black hole masses from spectroscopic surveys fundamentally rely on the reverberation sample, and thus our current understanding of the growth and evolution of black holes and galaxies across cosmic time relies on the accuracy of reverberation-based black hole masses. A stellar dynamical mass for NGC 6814 will increase by 50% the small sample of black holes that provide an independent check on the stability of the entire AGN black hole mass scale. We are also currently targeting additional AGNs for reverberation-mapping campaigns with the intent of further increasing this sample in the future.

Publications using this program's data