Nucleon strange $s\bar s$ asymmetry to the $\Lambda/\bar\Lambda$ fragmentation

TL;DR

This paper investigates how the asymmetry in strange quark-antiquark pairs in the nucleon influences the difference in longitudinal spin transfers to Lambda and anti-Lambda hyperons in semi-inclusive deep inelastic scattering, explaining experimental data.

Contribution

It introduces a light-cone quark-diquark model analysis that incorporates strange sea asymmetry and transverse momentum effects to explain spin transfer differences.

Findings

Strange sea asymmetry affects Lambda/anti-Lambda spin transfer difference.

Results align with COMPASS experimental data.

Transverse momentum constrains the sensitivity to strange sea asymmetry.

Abstract

The difference between the $\Lambda$ and $\bar \Lambda$ longitudinal spin transfers in the semi-inclusive deep inelastic scattering process is intensively studied. The study is performed in the current fragmentation region, by considering the intermediate hyperon decay processes and sea quark fragmentation processes, while the strange sea $s\bar s$ asymmetry in the nucleon is taken into account. The calculation in the light-cone quark-diquark model shows that the strange sea asymmetry gives a proper trend to the difference between the $\Lambda$ and $\bar \Lambda$ longitudinal spin transfers. When considering the nonzero final hadron transverse momentum, our results can explain the COMPASS data reasonably. The nonzero final hadron transverse momentum is interpreted as a natural constraint to the final hadron $z$ range where the longitudinal spin transfer is more sensitive to the strange sea $s\bar s$ asymmetry.