Transverse $\Lambda$ polarization in $e^+e^-$ annihilations and in SIDIS processes at the EIC within TMD factorization

TL;DR

This paper investigates transverse Lambda polarization in electron-positron annihilation and SIDIS at the EIC using TMD factorization, emphasizing charm contributions and isospin symmetry to improve polarization predictions.

Contribution

It introduces a detailed phenomenological analysis of Lambda polarization, incorporating charm effects and isospin symmetry within TMD formalism for the first time in this context.

Findings

Charm contributions significantly affect polarization predictions.

Isospin symmetry helps refine fragmentation function extraction.

Results inform future EIC measurements of Lambda polarization.

Abstract

We present a phenomenological study on the role of charm contribution and $SU(2)$ isospin symmetry in the extraction of the $\Lambda$ polarizing fragmentation functions from $e^+e^- \to \Lambda^\uparrow (\bar\Lambda^\uparrow) \,h + X$ annihilation processes. We adopt the well-established transverse-momentum-dependent factorization formalism, within the Collins-Soper-Sterman evolution scheme at next-to-leading logarithm accuracy, carefully exploiting the role of the nonperturbative component of the polarizing fragmentation function. We then discuss the impact of these results on the predictions for transverse $\Lambda$, $\bar{\Lambda}$ polarization in semi-inclusive deep inelastic scattering processes at typical energies of the future Electron-Ion Collider.