Nonrelativistic lattice study of stoponium

TL;DR

This study uses lattice nonrelativistic effective field theory to compute the properties of stoponium, revealing that lattice results for the wavefunction at the origin are significantly larger than potential model predictions.

Contribution

First lattice nonrelativistic effective field theory calculation of stoponium properties, providing new quantitative insights into its bound state characteristics.

Findings

Lattice $|R_{1S}(0)|^2/M_{1S}^3$ is 3.5 to 4 times larger than potential models.

Stoponium mass and wavefunction at the origin are computed using quenched lattice configurations.

Results suggest potential models may underestimate the wavefunction at the origin for stoponium.

Abstract

We calculate the bound state properties of stoponium using lattice formulation of nonrelativistic effective field theory for stop which is moving nonrelativistically in the rest frame of stoponium. Our calculation method is similar to that employed in lattice nonrelativistic quantum chromodynamics (NRQCD) studies for charmonium and bottominum. Using $16^3 \times 256$ quenched lattice gauge field configurations at $a^{-1} = 50(1) {\rm GeV}$, we obtain the stopoinium mass and the lattice matrix element which is related to the wavefunction at the origin for the $1S$ state and find that the lattice $|R_{1S} (0)|^2/M_{1S}^3$ is $3.5 \sim 4$ larger than that from a potential model calculation for $200 {\rm GeV} \le M_{1S} \le 800 {\rm GeV}$.