On the use of a heterogeneous MIMD-SIMD platform to simulate the dynamics of globular clusters with a central massive object

Abstract The dynamics of a large stellar (globular) cluster containing N =128,000 stars has been simulated using a direct summation ( O ( N 2 )) method and a heterogeneous platform. Preliminary simulations have been carried out on model systems with and without the presence, in their center of mass, of a black hole whose mass has been varied from 0.02 to 0.1 times the total mass of the cluster. These simulations followed the evolution of the globular cluster in order to describe its dynamics over an interval of time sufficiently large with respect to the internal crossing time. Computations have demonstrated that the platform heterogeneity, allowing a very efficient use of the computational resources, can be considered a key feature for sustaining large computational loads. Our results show that the massive object in the center of the cluster alters the surrounding star distribution very quickly; the following evolution is much slower, as it occurs via two-body collisional relaxation.

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