Work on the interplay among $h^+$, $h^{-}$ and hadron pair transverse spin asymmetries in SIDIS

TL;DR

This paper investigates the relationship between single-hadron and dihadron transverse spin asymmetries in SIDIS, providing evidence that both are influenced by a common underlying physical process, based on high-statistics COMPASS data.

Contribution

It offers new insights into the interplay between Collins and dihadron asymmetries, suggesting a shared physical origin, supported by analysis of extensive experimental data.

Findings

Both asymmetries are driven by a common physical process.

Strong indications of a connection between the mechanisms behind the asymmetries.

High-statistics data supports the unified interpretation.

Abstract

In the fragmentation of a transversely polarized quark a left-right asymmetry, the Collins asymmetry, is expected for each hadron produced in the process $\mu N \rightarrow \mu ' h^{+} h^{-} X$. Similarly, an asymmetry is also expected for the hadron pair, the dihadron asymmetry. Both asymmetries have been measured to be different from zero on transversely polarised proton targets and have allowed for first extractions of the transversity distributions. From the high statistics COMPASS data we have further investigated these asymmetries getting strong indications that the two mechanisms are driven by a common physical process.