Spin-up of low mass classical bulges in barred galaxies

Details Spin-up of low mass classical bulges in barred galaxies Spin-up of low mass classical bulges in barred galaxies

2011-05-29

arxiv.org/abs/1105.5797v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

15 pages, 16 figures, accepted for publication by MNRAS

Scientific paper

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 self-consistent high resolution {\it N}-body simulations, we study how an initially isotropic non-rotating small classical bulge absorbs angular momentum emitted by the bar. The basic mechanism of this angular momentum exchange is through resonances and a considerable fraction of the angular momentum is channeled through Lagrange point (-1:1) and ILR (2:1) orbits. In the phase of rapid dynamical growth, also retrograde non-resonant orbits absorb significant angular momentum. As a result of this angular momentum gain, the initially non-rotating classical bulge transforms into a fast rotating, radially anisotropic and triaxial object, embedded in the similarly fast rotating boxy bulge formed from the disk. Towards the end of the evolution, the classical bulge develops cylindrical rotation. By that time, its inner regions host a "classical bulge-bar" whose distinct kinematics could serve as direct observational evidence for the secular evolution in the galaxy. Some implications of these results are discussed briefly.

Affiliated with

Also associated with

No associations

Rating

Spin-up of low mass classical bulges in barred galaxies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spin-up of low mass classical bulges in barred galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spin-up of low mass classical bulges in barred galaxies will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-289945