Kinematic effects of tidal interaction on galaxy rotation curves

We use self-consistent N-body models in conjunction with models of test par ticles moving in galaxy potentials to explore the initial effects of intera ctions on the rotation curves of spiral galaxies. Using nearly self-consist ent disk/bulge/halo galaxy models, we simulate the first pass of galaxies o n nearly parabolic orbits; we vary orbit inclinations, galaxy halo masses, and impact parameters. For each simulation, we mimic observed rotation curv es of the model galaxies. Transient interaction-induced features of the cur ves include distinctly rising or falling profiles at large radii and pronou nced bumps in the central regions. Remarkably similar features occur in our statistical sample of optical emission-line rotation curves of spiral gala xies in tight pairs and n-tuples.