Globular clusters captured by the Milky Way’s bar

Abstract

Equations of motion are integrated backwards in time by 5 Gyr for thirty globular clusters from the central parts of the Milky Way. We considered two models of the potential, one, which is obtained by fitting the velocity curve of the Milky Way, and the second one, which is based on the results of N-body simulations. Obtained orbits were studied within the approach of spectral dynamics: main frequency of oscillations fx and fR were calculated for each of the orbits. Our analysis showed that six of the studied gloubular clusters (NGC 6266, NGC 6642, Terzan 1, Terzan 2, Terzan 4, and Terzan 5) have frequencies ratios fR/fx ≈ 2, that is, they can support the bar in the considered models.