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Adiabatic invariants in stellar dynamics. 1: Basic conceptsThe adiabatic criterion, widely used in astronomical dynamics, is based on the harmonic oscillator. It asserts that the change in action under a slowly varying perturbation is exponentially small. Recent mathematical results that precisely define the conditions for invariance show that this model does not apply in general. In particular, a slowly varying perturbation may cause significant evolution stellar dynamical systems even if its time scale is longer than any internal orbital time scale. This additional 'heating' may have serious implications for the evolution of star clusters and dwarf galaxies which are subject to long-term environmental forces. The mathematical developments leading to these results are reviewed, and the conditions for applicability to and further implications for stellar systems are discussed. Companion papers present a computational method for a general time-dependent disturbance and detailed example.
Document ID
19950032392
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Weinberg, Martin D. (Univ. of Massachusetts, Amherst, MA United States)
Date Acquired
August 16, 2013
Publication Date
October 1, 1994
Publication Information
Publication: The Astronomical Journal
Volume: 108
Issue: 4
ISSN: 0004-6256
Subject Category
ASTROPHYSICS
Funding Number(s)
CONTRACT_GRANT: NSF PHY-89-04035
CONTRACT_GRANT: NAGW-2224
Distribution Limits
Public
Copyright
Other