Pion vector form factor from LapH-smeared currents in lattice QCD

Frank X. Lee; Andrei Alexandru

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arXiv · 2610.34397

Pion vector form factor from LapH-smeared currents in lattice QCD

Frank X. Lee·Andrei Alexandru

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Abstract

We explore a method to extract pion vector form factor from three-point functions using currents constructed from LapH-smeared quark fields. LapH employs the low eigenmodes of the Laplacian Heaviside operator on the lattice to smear out the quark fields in spatial directions. The LapH-smeared quark propagator retains all symmetry properties of the original one and can be re-used to construct correlation functions at a reduced cost, with equal treatment of connected and disconnected diagrams. The calculations are performed on a two-flavor dynamical nHYP-smeared ensemble on the $24^3\times 48$ lattice at a spacing of 0.12 fm and pion mass of 315 MeV. We show that an extrapolation in the number of low eigenmodes in the LapH subspace can reproduce the same form factor computed from the conventional SST method with point source, sink, and current. The study opens up the possibility of applying LapH-smeared currents to extract hadron form factors and polarizabilities including disconnected diagrams.

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Frank X. Lee, Andrei Alexandru. 2026-10-25. Pion vector form factor from LapH-smeared currents in lattice QCD. https://arxiv.org/abs/2610.34397

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