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arXiv · 1903.04857

Asymptotics for the Sasa--Satsuma equation in terms of a modified Painlev\'e II transcendent

Lin Huang·Jonatan Lenells
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Abstract

We consider the initial-value problem for the Sasa-Satsuma equation on the line with decaying initial data. Using a Riemann-Hilbert formulation and steepest descent arguments, we compute the long-time asymptotics of the solution in the sector $|x| \leq M t^{1/3}$, $M$ constant. It turns out that the asymptotics can be expressed in terms of the solution of a modified Painlev\'e II equation. Whereas the standard Painlev\'e II equation is related to a $2 \times 2$ matrix Riemann-Hilbert problem, this modified Painlev\'e II equation is related to a $3 \times 3$ matrix Riemann--Hilbert problem.

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Lin Huang, Jonatan Lenells. 2019-03-12. Asymptotics for the Sasa--Satsuma equation in terms of a modified Painlev\'e II transcendent. https://arxiv.org/abs/1903.04857

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