Orbits supporting bars within bars

Nov, 1999
18 pages
Published in:
  • Mon.Not.Roy.Astron.Soc. 313 (2000) 745
e-Print:

Citations per year

200020062012201820230246810
Abstract: (arXiv)
High-resolution observations of the inner regions of barred disk galaxies have revealed many asymmetrical, small-scale central features, some of which are best described as secondary bars. Because orbital time-scales in the galaxy center are short, secondary bars are likely to be dynamically decoupled from the main kiloparsec-scale bars. Here, we show that regular orbits exist in such doubly-barred potentials and that they can support the bars in their motion. We find orbits in which particles remain on loops: closed curves which return to their original positions after two bars have come back to the same relative orientation. Stars trapped around stable loops could form the building blocks for a long-lived, doubly-barred galaxy. Using the loop representation, we can find which orbits support the bars in their motion, and what are the constraints on the sizes and shapes of self-consistent double bars. In particular, it appears that a long-lived secondary bar may exist only when an Inner Lindblad Resonance is present in the primary bar, and that it would not extend beyond this resonance.
      • Erratum-ibid.S 2 328
      • Erratum-ibid.S 2 345
      • NOONE A 0 92
      • Vistas Astron. 14 163
      • NOONE 1 784
      • NOONE J 4 84
      • Astron.Astrophys.S 1 479
      • Astron.Zh. 33 27
      • NOONE 2 337
      • NOONE S 9 1999
      • Addendum-ibid.S 1 299
      • NOONE 1 65
      • NOONE P 1 373
      • Addendum-ibid.J 1 385
      • NOONE J 4 165