Flavor asymmetry of the nucleon

TL;DR

This paper investigates the flavor asymmetry in the nucleon sea using an unquenched quark model that explicitly includes quark-antiquark pairs, successfully explaining the observed excess of anti-d over anti-u quarks.

Contribution

It introduces an unquenched quark model for baryons that explicitly incorporates quark-antiquark pairs to explain nucleon sea flavor asymmetry.

Findings

The model predicts an excess of anti-d over anti-u quarks in the proton.

Results align with experimental observations of nucleon sea asymmetry.

Provides a theoretical framework for understanding sea quark distributions.

Abstract

The flavor asymmetry of the nucleon sea is discussed in an unquenched quark model for baryons in which the effects of quark-antiquark pairs (u anti-u, d anti-d and s anti-s) are taken into account in an explicit form. The inclusion of q anti-q pairs leads automatically to an excess of anti-d over anti-u quarks in the proton, in agreement with experimental data.