Masses of the central black holes in low mass early-type galaxies
using LGS AO

I will present the first determination of masses (Mbh) of
suppermassive black holes (SMBHs) using laser guide star adaptive
optics (LGS AO) observations. These results are part of an ongoing
program at GEMINI using NIFS and ALTAIR in LGS AO mode to observe a
significant number of low-mass early-type galaxies and determine their
SMBHs, in order to improve on present scaling relation between the
SMBHs and properties of the host galaxies. The first targets were
chosen to have a central light profile showing a core (NGC524) and a
cusp (NGC2549), to probe the feasibility of using the galaxy center as
the natural guide source required for LGS AO observations. The
observations are done with an innovative technique where the focus
compensation due to the changing distance to the sodium layer is made
'open loop', allowing the extended galaxy nuclei to be used only for
tip-tilt correction. The data have spatial resolution of 0.12 and 0.16
arcseconds, where at least 40 % of flux comes within 0.2 arcseconds,
showing that high quality LGS AO observations of these objects are
possible. The spatial resolution of the data is sufficiently high to
extract stellar kinematics using the CO bandhead, which can constrain
the stellar dynamical models based on the Schwarzschild's method and
derive robust estimates of the SMBHs. These models are also used to
determine the internal orbital structure and test the scenarios of the
SMBH formation. In my contribution, I will present the observations,
the models and the estimated SMBHs, focusing on the method for
determining the final PSF of the LGS AO observations and the influence
of the derived SMBHs to the central orbital structures of these two
galaxies.