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arXiv · 1412.8586

Painlev\'e III asymptotics of Hankel determinants for a perturbed Jacobi weight

Zhao-Yun Zeng·Shuai-Xia Xu·Yu-Qiu Zhao
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Abstract

We study the Hankel determinants associated with the weight $$w(x;t)=(1-x^2)^{\beta}(t^2-x^2)^\alpha h(x),~x\in(-1,1),$$ where $\beta>-1$, $\alpha+\beta>-1$, $t>1$, $h(x)$ is analytic in a domain containing $[-1,1]$ and $h(x)>0$ for $x\in[-1,1]$. In this paper, based on the Deift-Zhou nonlinear steepest descent analysis, we study the double scaling limit of the Hankel determinants as $n\to \infty$ and $t\to 1$. We obtain the asymptotic approximations of the Hankel determinants, evaluated in terms of the Jimbo-Miwa-Okamoto $\sigma$-function for the Painlev\'{e} III equation. The asymptotics of the leading coefficients and the recurrence coefficients for the perturbed Jacobi polynomials are also obtained.

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Zhao-Yun Zeng, Shuai-Xia Xu, Yu-Qiu Zhao. 2014-12-30. Painlev\'e III asymptotics of Hankel determinants for a perturbed Jacobi weight. https://arxiv.org/abs/1412.8586

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