Simulations of Stellar Collisions Involving Pre-Main-Sequence Stars

In this paper, we present the results of smoothed particle hydrodynamic (SPH) simulations of collisions between pre-main-sequence stars and a variety of other kinds of stars. Simulations over a range of impact parameters and velocities were performed. We find that pre-main-sequence stars tend to "wrap" themselves around their impactor. We discuss the probable evolutionary state of products of collisions between pre-main-sequence stars and pre-main-sequence, main-sequence, giant branch, and compact stars. The nature of the collision product does not depend strongly on the impact parameter or the velocity of the collision.