Nekhoroshev{stability of L4 and L5 in the Spatial Restricted Three{body Problem
نویسندگان
چکیده
We show that L 4 and L 5 in the spatial restricted circular three{body problem are Nekhoroshev{ stable for all but a few values of the reduced mass up to the Routh critical value. This result is based on two extensions of previous results on Nekhoroshev{stability of elliptic equilibria, namely to the case of`directional quasi{convexity', a notion introduced here, and to a (non-convex) steep case. We verify that the hypotheses are satissed for L 4 and L 5 by means of numerically constructed Birkhoo normal forms.
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