Effects of collisions and interactions on star formation in galaxy pairs in the field

Abstract

By using cosmological simulations, we study the effect of galaxy interactions on star formation activity in low density regions of the local Universe (z < 0.1). To define galaxy pairs we have used the relative separation and radial velocity V criteria following the observational selections (Lambas et al, 2003). From our statistically analysis, we find that closed encounters at low relative velocity produce a significantly enhancement over that of isolated galaxies with similar redshifts in the field. To compare our results with observations, we analyze not only tridimensional catalog of galaxy pairs, but also we built a 2D catalog emulating observational data. Results from both 2D and 3D simulated catalog show that tendencies found between star formation rate and relative separations and radial velocities coincide with observational results. Finally, from the projected catalog we can determine the effect on the results produced by spurious pairs introduced by projection.