Lyapunov and diffusion timescales in the solar neighborhood

Abstract

We estimate the Lyapunov times (characteristic times of predictability of motion) in Quillen's models for the dynamics in the solar neighborhood. These models take into account perturbations due to the Galactic bar and spiral arms. For estimating the Lyapunov times, an approach based on the separatrix map theory is used. The Lyapunov times turn out to be typically of the order of 10 Galactic years. We show that only in a narrow range of possible values of the problem parameters the Galactic chaos is adiabatic; usually it is not slow. We also estimate the characteristic diffusion times in the chaotic domain. In a number of models, the diffusion times turn out to be small enough to permit migration of the Sun from the inner regions of the Milky Way to its current location. Moreover, due to the possibility of ballistic flights inside the chaotic layer, the chaotic mixing might be even far more effective and quicker than in the case of normal diffusion. This confirms the dynamical possibility of Minchev and Famaey's migration concept.

22 pages, including 2 figures. Published in Astrophys. J., 733, 39

References in corpus (4)

• Radial migration in galactic disks caused by resonance overlap of multiple patterns: Self-consistent simulations
• Marginal resonances and intermittent behaviour in the motion in the vicinity of a separatrix
• The width of a chaotic layer
• On the maximum Lyapunov exponent of the motion in a chaotic layer

Cited by in corpus (18)

• Chemodynamical evolution of the Milky Way disk I: The solar vicinity
• Stellar Population gradients in galaxy discs from the CALIFA survey
• Evolution of Galactic Discs: Multiple Patterns, Radial Migration and Disc Outskirts
• Radial Migration Does Little for Galactic Disc Thickening
• Evolution of the Milky Way with radial motions of stars and gas I. The solar neighborhood and the thin and thick disk
• Structure in phase space associated with spiral and bar density waves in an N-body galactic disk
• Stellar diffusion in barred spiral galaxies
• Lyapunov exponents in resonance multiplets
• The BaLROG project - I. Quantifying the influence of bars on the kinematics of nearby galaxies
• Massive identification of asteroids in three-body resonances
• The BaLROG project - II. Quantifying the influence of bars on the stellar populations of nearby galaxies
• Dynamics and Morphology of the Milky Way Spiral Arms from the Metallicity Distribution and Radial Mixing
• Constraining the Milky Way assembly history with Galactic Archaeology. Ludwig Biermann Award Lecture 2015
• Searching for Possible Siblings of the Sun from a Common Cluster based on Stellar Space Velocities
• On the relevance of chaos for halo stars in the solar neighbourhood II
• Galactic Kinematics from OB3 Stars with Distances determined from Interstellar Ca II Lines
• Habitability properties of circumbinary planets
• New Observational Constraints to Milky Way Chemodynamical models