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arXiv · 2609.11343

Cartesian PML truncation for the Helmholtz equation is exponentially accurate at high frequency

Martin Averseng·Jeffrey Galkowski·Euan A. Spence
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Abstract

For a wide class of Helmholtz scattering problems (namely, those fitting in the black-box framework of Sjöstrand--Zworski) we prove that the error incurred by approximating the radiation condition by a Cartesian perfectly-matched layer (PML) decreases exponentially in the width of the PML, the strength of the PML scaling, and the frequency.

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Martin Averseng, Jeffrey Galkowski, Euan A. Spence. 2026-09-10. Cartesian PML truncation for the Helmholtz equation is exponentially accurate at high frequency. https://arxiv.org/abs/2609.11343

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