Strangeness and charm content of the nucleon

TL;DR

This paper investigates the scalar strangeness and charm contents of the nucleon, providing preliminary quantitative estimates using lattice QCD configurations, which are relevant for understanding nucleon structure and its quark contributions.

Contribution

It offers new lattice QCD results on the nucleon's strangeness and charm content, including preliminary values for the strange quark mass fraction and spin contribution.

Findings

f_{T_s} = 0.070(22) for strange quark mass fraction

Delta s = -0.015(10) for strangeness spin contribution

Results obtained on two-flavor non-perturbatively improved configurations

Abstract

We present results on the scalar strangeness and charm contents of the nucleon and of the disconnected contributions to the nucleon spin. These are obtained on two flavour non-perturbatively improved Sheikholeslami-Wilson configurations at a pseudoscalar mass of 290 MeV. We quote f_{T_s} = m_s<N|ss|N>/m_N< = 0.070(22) as our preliminary value for the strange quark fraction of the nucleon mass and a modified minimal subtraction scheme value Delta s = -0.015(10), with as yet unknown systematics, for the strangeness contribution to the spin.