NEW STABLE METHOD FOR LONG-TIME INTEGRATION IN A N-BODY PROBLEM

Tanya Taidakova
CrAO

Session ID: P5.06   Type: poster

Abstract:

The most serious error of numerical simulations is the accumulation of discretization error due to a finite stepsize. The traditional integrators such as Runge-Kutta methods and multistep methods cause linear secular errors to the energy etc, which means that the semi-major axis and another orbital elements change linearly with time.

Potter [1] described the implicit second-order numerical method for particles in a plasma with magnetic field. We modificate this method and use for dynamics of particles around planet (or star) in the corotating coordinate system [2,3]. A big advantage of this numerical method is its absolute stability: the error depends only on the step size and does not accumulate with increasing number of time steps. In addition, this scheme takes less computing time (by a factor of approximately 1.5-2) than the second-order Runge-Kutta method. We tested this method for few astronomical system [2] and for motion of a asteroid in 1:1 Jupiter' resonance during 200 millions time steps [3].

References:

  1. Potter, D. Computational Physics, John Wiley and Sons Ltd., London-New York-Sydney-Toronto, 1973.
  2. Taidakova, T.A./The numerical analysis of the dynamics of particles about the planets. I. Four-bodies problem.// Nauch.Informacii Astronomicheskogo Soveta Akademii Nauk SSSR. - Riga, Zinatne, 1990. Iss.68. Ó.72-81.
  3. Taidakova, T.A. ``Numerical Analysis of Dynamics of the Solar System Bodies''. Ph.D.Thesis, Moscow State University, Moscow, 1995.




Patrick P. Murphy
Wed Sep 11 14:53:19 EDT 1996