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J. Bak (Ohio University)
Counter rotating cores have been observed in a number of elliptical galaxies. A suggested method of formation, is one in which dynamical friction causes a compact companion to spiral into the center of a much larger elliptical galaxy on a retrograde orbit relative to the larger galaxy's rotation. If the core of the smaller galaxy is not tidally disrupted, it may carry some of its orbital angular momentum to the center. I present results from N-body simulations of counter rotating core formation by satellite accretion. 2D line of sight velocities fields, including third and fourth order Gauss-Hermite terms, are created using the penalized likelihood method of Merritt. The photometric aspects of the simulations are analyzed with IRAF to provide a comparison with observations. The results indicate that dissipationless accretion of a satellite is unable to form counter rotating cores. In the cases where the satellite does not disrupt, streaming through the center of the larger galaxy transforms the satellite into a bar, which is subsequently forced by dynamical friction to rotate in the prograde direction. Results from similar simulations involving dissipation are also presented, to determine if allowing for small amounts of gas in the satellite affects the dissipationless results by preventing tidal disruption or inhibiting bar formation.