Dynamical Decoupling of Nested Bars: Self-Gravitating Gaseous Nuclear Bars

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

7 pages, 4 postscript figures. (The associated MPEG movie can be requested from the authors directly.) Submitted to Astrophysi

Scientific paper

10.1086/427280

A substantial fraction of barred galaxies host additional nuclear bars which tumble with pattern speeds exceeding those of the large-scale (primary) stellar bars. We have investigated the mechanism of formation and dynamical decoupling in such nested bars which include gaseous (secondary) nuclear bars within the full size galactic disks, hosting a double inner Lindblad resonance. Becoming increasingly massive and self-gravitating, the nuclear bars lose internal (circulation) angular momentum to the primary bars and increase their strength. Developing chaos within these bars triggers a rapid gas collapse -- bar contraction. During this time period, the secondary bar pattern speed Omega_s~a^{-1}, where "a" stands for the bar size. As a result, Omega_s increases dramatically until a new equilibrium is reached (if at all), while the gas specific angular momentum decreases -- demonstrating the dynamical decoupling of nested bars. Viscosity, and therefore the gas presence, appears to be a necessary condition for the prograde decoupling of nested bars. This process maintains an inflow rate of ~1 M_o/yr over ~10^8 yrs across the central 200 pc and has important implications for fueling the nuclear starbursts and AGN.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Dynamical Decoupling of Nested Bars: Self-Gravitating Gaseous Nuclear Bars 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 Dynamical Decoupling of Nested Bars: Self-Gravitating Gaseous Nuclear Bars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dynamical Decoupling of Nested Bars: Self-Gravitating Gaseous Nuclear Bars will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-718297

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.