Soft pions at high energy as an origin of flavor asymmetry of the light sea quarks in the nucleon

TL;DR

This paper estimates the contribution of soft pions to the nucleon's structure function, revealing they cause significant flavor asymmetry in light sea quarks and account for a substantial part of the Gottfried sum deficit.

Contribution

It introduces a method to quantify soft pion effects on nucleon structure functions, linking soft pion theory to observed flavor asymmetries in sea quarks.

Findings

Soft pions contribute 30-50% to the NMC Gottfried sum deficit.

Soft pion contribution causes large flavor asymmetry in light sea quarks.

The approach connects soft pion theorems with experimental structure function data.

Abstract

By using the soft pion theorem in the inclusive reactions, soft pions' contribution to the structure function $F_2$ in the nucleon is estimated. It is shown that this contribution produces such a large flavor asymmetry in the light sea quark distributions that it gives about $30\sim 50 %$ of the NMC deficit in the Gottfried sum.