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Hyperasymptotics and the Stokes' phenomenon

Published online by Cambridge University Press:  14 November 2011

A. B. Olde Daalhuis
Affiliation:
CWI, P.O. Box 4079, 1009 AB Amsterdam, The Netherlands aod©cwi.nl

Synopsis

Hyperasymptotic expansions were recently introduced by Berry and Howls, and yield refined information by expanding remainders in asymptotic expansions. In a recent paper of Olde Daalhuis, a method was given for obtaining hyperasymptotic expansions of integrals that represent the confluent hypergeometric U-function. This paper gives an extension of that method to neighbourhoods of the so-called Stokes lines. At each level, the remainder is exponentially small compared with the previous remainders. Two numerical illustrations confirm these exponential improvements.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1993

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