Multidimensional partial wave analysis of SIDIS dihadron beam spin asymmetries at CLAS12

TL;DR

This paper presents a multidimensional partial wave analysis of SIDIS dihadron beam spin asymmetries at CLAS12, revealing new insights into nucleon structure and hadronization through empirical measurements of spin-dependent fragmentation functions.

Contribution

It introduces a comprehensive multidimensional partial wave analysis of dihadron asymmetries, providing new empirical data and insights into spin-momentum correlations in hadronization.

Findings

First empirical evidence of nonzero $G_1^\perp$ at CLAS12

Point-by-point extraction of the subleading-twist PDF $e(x)$

Observation of different asymmetry behaviors across invariant mass regions

Abstract

Dihadron beam spin asymmetries provide a wide range of insights into nucleon structure and hadronization. Recent measurements at CLAS12 provide the first empirical evidence of nonzero $G_1^\perp$, the parton helicity-dependent dihadron fragmentation function (DiFF) encoding spin-momentum correlations in hadronization. These measurements also allow for a point-by-point extraction of the subleading-twist PDF $e(x)$ in a collinear framework. We observe different behavior of the asymmetries in different invariant mass regions, motivating a fully multidimensional study. The DiFFs also expand in terms of partial waves, each corresponding to the interference of dihadrons of particular polarizations. Altogether a fully multidimensional partial wave analysis is needed, and this presentation will summarize the efforts and results obtained thus far.