# Non-perturbative O(a) improvement of the SU(3) sextet model

## TL;DR

This paper non-perturbatively determines the improvement coefficient c_sw for the SU(3) gauge theory with two sextet fermions, enhancing lattice simulations by reducing discretization errors.

## Contribution

It provides the first non-perturbative calculation of c_sw for the SU(3) sextet model using Schrödinger functional methods with two different gauge discretizations.

## Key findings

- Calculated c_sw values for Wilson plaquette and Symanzik actions
- Improves accuracy of lattice simulations for the SU(3) sextet model
- Facilitates more precise studies of beyond Standard Model theories

## Abstract

We calculate non-perturbatively the coefficient c_sw required for O(a) improvement of the SU(3) gauge theory with Nf = 2 fermions in the two-index symmetric (sextet) representation. For the calculations we impose the standard improvement condition in the Schr\"odinger functional framework, using two different discretisations for the gauge field i.e. the Wilson plaquette action and the tree-level improved Symanzik (L\"uscher-Weisz) action.