Warping of Disk Galaxies by Passing Galaxies

We investigate the effects an interacting galaxy, the 'intruder', has on the shape of a disk galaxy with the aim of determining the cause of integral shaped warps in the disk. Using N-body simulations, we investigate the ways in which an intruder causes a spiral galaxy to warp as a function of the angle of passage, relative speed, relative masses, and distance between the two galaxies. The intruder is simulated by a point particle so that it effectively represents massive galaxies of any class. We present results of a systematic study of interaction parameters for the warping of galaxies without halos, and preliminary results of interactions on spiral galaxies with dark matter halos. In both cases, using plausible interaction parameters, we find that our simulations produce significant warps with amplitudes comparable to observations. We propose that warps in disk galaxies created by this dynamic are caused by pseudoforces generated in the interaction between the two galaxies.