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Integrable approximation of regular regions with a nonlinear resonance chain

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 نشر من قبل Clemens L\\\"obner
 تاريخ النشر 2014
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Julius Kullig




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Generic Hamiltonian systems have a mixed phase space where regions of regular and chaotic motion coexist. We present a method for constructing an integrable approximation to such regular phase-space regions including a nonlinear resonance chain. This approach generalizes the recently introduced iterative canonical transformation method. In the first step of the method a normal-form Hamiltonian with a resonance chain is adapted such that actions and frequencies match with those of the non-integrable system. In the second step a sequence of canonical transformations is applied to the integrable approximation to match the shape of regular tori. We demonstrate the method for the generic standard map at various parameters.



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