Major merging of galaxies in multicomponent numerical models: mass loss and exchange

Abstract

Abstract The process of collision of two multicomponent galaxies is considered in detail based on numerical simulations of the dynamics of gravitating gas, stars and dark mass. To solve the equations of motion of the gas component, we use the Smoothed Particle Hydrodynamics method. Modeling of collisionless components is based on the N-body model. The computations of gravitational forces are carried out using both the approximate hierarchical TreeCode algorithm and the direct method of summing the gravitational contribution from all particles, which provides an accurate solution. This approach allows testing various models and evaluating the resulting errors associated with the calculation of gravitational forces and a finite number of particles in each of the components. Both methods for calculating gravity are software implemented as parallel codes for Nvidia Tesla GPUs. The estimates of the lost mass and the efficiency of matter exchange between galaxies are discussed depending on the model parameters.