Physical Sciences and Mathematics Commons^™

Perturbations Of Spherical Stellar Systems During Flyby Encounters, E Vesperini, Md Weinberg

Astronomy Department Faculty Publication Series

We study the internal response of a galaxy to an unbound encounter and present a survey of orbital parameters covering typical encounters in different galactic environments. Overall, we conclude that relatively weak encounters by low-mass interloping galaxies can cause observable distortions in the primaries. The resulting asymmetries may persist long after the interloper is evident. We focus our attention on the production of structure in dark halos and in cluster elliptical galaxies. Any distortion produced in a dark halo can distort the embedded stellar disk, possibly leading to the formation of lopsided and warped disks. We show that distant encounters …