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arXiv · 2603.15231

Electric Polarizability of Charged Pions from nHYP Four-Point Functions

Benjamin Luke·Sudip Shiwakoti·Shayan Nadeem·Andrei Alexandru·Walter Wilcox·Frank X. Lee
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Abstract

Understanding a hadron's electric and magnetic polarizabilities allows one to access internal structural information. Traditionally, the external field two-point function method has been used to calculate polarizabilities. However, recent work has demonstrated the effectiveness of using four-point functions for computing polarizabilities of charged and neutral hadrons. Our previous study on the electric polarizability of the charged pion used a quenched Wilson action on a lattice with pion mass from 1100 MeV to 370 MeV. In this work, we employ a number of improvements, including a dynamical action (nHYP), smaller pion masses (220 MeV and 315 MeV), and a variable lattice size in order to extrapolate to infinite volume. Preliminary results are presented.

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Benjamin Luke, Sudip Shiwakoti, Shayan Nadeem, Andrei Alexandru, Walter Wilcox, Frank X. Lee. 2026-03-16. Electric Polarizability of Charged Pions from nHYP Four-Point Functions. https://arxiv.org/abs/2603.15231

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