Description |
Secular evolution is one of the key routes through which galaxies evolve along the Hubble sequence. Not only the disk undergoes morphological and kinematic changes, but also a preexisting classical bulge may be dynamically changed by the secular processes driven primarily by the bar. We study the influence of a growing bar on the dynamical evolution of a low mass classical bulge such as might be present in galaxies like the Milky Way. Using high resolution N-body simulation, it is shown that an initially non-rotating low mass classical bulge absorbs angular momentum emitted by the bar. The basic mechanism of this angular momentum exchange is through resonances. As a result of this angular momentum gain, the initially non-rotating classical bulge transforms into a fast rotating, radially anisotropic and triaxial object. Towards the end of the evolution, the classical bulge develops cylindrical rotation. Some implications of these results will be discussed briefly.
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