Substructures in Minor Mergers' Tidal Streams

D. A. Noreña, J. C. Muñoz-Cuartas, L. F. Quiroga, N. Libeskind

Published 2019-08-20Version 1

In this work, we explore the idea that substructures like stellar clusters could be formed from the tidal stream produced in galactic minor mergers. We use $N$-body and SPH simulations of satellite galaxies interacting with a larger galaxy. We study the distribution of mass in streams to identify overdensity regions in which a substructure could be formed. We found that without gas, no substructure formed as none of the overdensities shows a definite morphology nor dynamical stability. Including gas we found that several clumps appear and proved to be real long standing physical structures ($t \geq$ 1 Gyr). We analyzed the orbits, ages and masses of these structures, finding its correspondence with the halo subsystems. We conclude that it is possible to form cluster-like structures from the material in tidal streams and found evidence in favour of the presence of dark matter in these systems.