Distillation at High-Momentum

TL;DR

This paper extends the momentum smearing technique within the distillation framework in Lattice QCD, enabling reliable extraction of high-momentum hadronic observables up to approximately 3 GeV.

Contribution

The work introduces modifications to distillation to incorporate momentum smearing, improving access to high-momentum hadronic observables in Lattice QCD.

Findings

Ground-state nucleon energies reliably extracted up to 3 GeV

Matrix elements with large momentum dependence resolved

Enhanced time slice sampling improves statistical quality

Abstract

Extraction of hadronic observables at finite-momenta from Lattice QCD (LQCD) is constrained by the well-known signal-to-noise problems afflicting all such LQCD calculations. Traditional quark smearing algorithms are commonly used tools to improve the statistical quality of hadronic $n$-point functions, provided operator momenta are small. The momentum smearing algorithm of Bali et al. extends the range of momenta that are cleanly accessible, and has facilitated countless novel lattice calculations. Momentum smearing has, however, not been explicitly demonstrated within the framework of distillation. In this work we extend the momentum-smearing idea, by exploring a few modifications to the distillation framework. Together with enhanced time slice sampling and expanded operator bases engendered by distillation, we find ground-state nucleon energies can be extracted reliably for $\left|\vec{p}\right|\lesssim3\text{ GeV}$ and matrix elements featuring a large momentum dependence can be resolved.