A high precision mass measurement of the central black hole in the massive elliptical galaxy NGC 2513 with ALMA molecular gas dynamics
Résumé
Supermassive black holes (SMBH) are believed to co-evolve with their host galaxies. Evidence for this co-evolution is found in the form of several correlations between the SMBH mass and various properties of the host galaxy, the tightest of which is the bulge stellar velocity dispersion. In order to better understand these correlations, a large and robust dataset of SMBH measurements is required, particularly in the low- and high-mass regime where measurements are still relatively few.
In this talk, I present the results of a mass measurement of the putative SMBH in the massive elliptical galaxy NGC 2513. The measurement is obtained via the method of cold molecular gas dynamics, using high resolution ALMA (Atacama Large Millimetre/sub-millimetre Array) observations. I introduce the method, its advantages and limitations. I then present how I derive the luminous mass using near-infrared images from the Hubble Space Telescope, taking detailed dust masking into account. This is a necessary step, as an accurate knowledge of the luminous mass of the galaxy is crucial towards obtaining a precise SMBH mass measurement. I then present how I combine different CO(2-1) ALMA observations to obtain the highest possible resolution at a sufficient sensitivity. By forward modelling the resulting ALMA datacube with the KinMS (KINematic Molecular Simulation) routines developed by Davis et al. (2013), a best-fit model to the data is attained. Finally, I discuss my SMBH mass measurement with respect to different SMBH evolution scenarios and future requirements needed to significantly advance the field.