  Experiments and simulations from a variety of sample sizes indicated that the
centrifugal force significantly affects rotating Rayleigh-B\'enard
convection-patterns. In a large-aspect-ratio sample, we observed a hybrid state
consisting of domain chaos close to the sample center, surrounded by an annulus
of nearly-stationary nearly-radial rolls populated by occasional defects
reminiscent of undulation chaos. Although the Coriolis force is responsible for
domain chaos, by comparing experiment and simulation we show that the
centrifugal force is responsible for the radial rolls. Furthermore, simulations
of the Boussinesq equations for smaller aspect ratios neglecting the
centrifugal force yielded a domain precession-frequency $f\sim\epsilon^\mu$
with $\mu\simeq1$ as predicted by the amplitude-equation model for domain
chaos, but contradicted by previous experiment. Additionally the simulations
gave a domain size that was larger than in the experiment. When the centrifugal
force was included in the simulation, $\mu$ and the domain size closely agreed
with experiment.
