  Spectroscopic observations of three lenticular (S0) galaxies (NGC 1167, NGC
4150, and NGC 6340) and one SBa galaxy (NGC 2273) have been taken with the 6-m
telescope of the Special AstrophysicalObservatory of the Russian Academy of
Sciences aimed to study the structure and kinematic properties of early-type
disk galaxies. The radial profiles of the stellar radial velocities and the
velocity dispersion are measured. N-body simulations are used to construct
dynamical models of galaxies containing a stellar disk, bulge, and halo. The
masses of individual components are estimated formaximum-mass disk models. A
comparison of models with estimated rotational velocities and the stellar
velocity dispersion suggests that the stellar disks in lenticular galaxies are
"overheated"; i.e., there is a significant excess velocity dispersion over the
minimum level required to maintain the stability of the disk. This supports the
hypothesis that the stellar disks of S0 galaxies were subject to strong
gravitational perturbations. The relative thickness of the stellar disks in the
S0 galaxies considered substantially exceed the typical disk thickness of
spiral galaxies.
