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Adiabatic Invariants in Stellar Dynamics: III. Application to Globular Cluster Evolution

Martin D. Weinberg
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Abstract

The previous two companion papers demonstrate that slowly varying perturbations do not result in adiabatic cutoffs and provide a formalism for computing the long-term effects of time-dependent perturbations on stellar systems. Here, the theory is implemented in a Fokker-Planck code and a suite of runs illustrating the effects of shock heating on globular cluster evolution are described. Shock heating alone results in considerable mass loss for clusters with $R_g\lta8\kpc$: a concentration $c=1.5$ cluster with $R_g=8\kpc$ loses up to $95\%$ of its initial mass in $15\Gyr$. Only those with concentration $c\lta1.3$ survive disk shocks inside of this radius. Other effects, such as mass loss by stellar evolution, will increase this survival bound. Loss of the initial halo together with mass segregation leads to mass spectral indices, $x$, which may be considerably larger than their initial values.

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Martin D. Weinberg. 1994-04-07. Adiabatic Invariants in Stellar Dynamics: III. Application to Globular Cluster Evolution. https://doi.org/10.1086/117163

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