Kotzinian-Mulders effect in semi-inclusive DIS within TMD factorization * *Supported by the National Natural Science Foundation of China (12075043)

Xuan Luo,Hao Sun

doi:10.1088/1674-1137/ac3124

Abstract

In this study, we investigate the Kotzinian-Mulders effect under semi-inclusive deep inelastic scattering (SIDIS) within the framework of transverse momentum dependent (TMD) factorization. The asymmetry is contributed by the convolution of the Kotzinian-Mulders function and the unpolarized fragmentation function . As a TMD distribution, the Kotzinian-Mulders function in the coordinate space in the perturbative region can be represented as the convolution of the C-coefficients and the corresponding collinear correlation function. The Wandzura-Wilczek approximation is used to obtain this correlation function. We perform a detailed phenomenological numerical analysis of the Kotzinian-Mulders effect in the SIDIS process within TMD factorization at the kinematics of the HERMES and COMPASS experiments. We observe that the obtained -, -, and -dependent Kotzinian-Mulders effects are basically consistent with the HERMES and COMPASS measurements. We also make predictions at EIC and EicC kinematics.

Highlights

The investigation of the internal structure of the nucleon remains a frontier of hadronic physics research
The semi-inclusive deep inelastic scattering (SIDIS) cross section can be factorized into transverse momentum dependent (TMD) parton distribution functions (PDFs) having the information of the active quark distributions with transverse momentum in the parent proton and the TMD parton fragmentation functions (FFs) illustrating the hadronizations of the struck quarks into the detected hadrons
Similar phenomenological studies for asymmetries contributed by Sivers, Boer-Mulders, and Collins functions are discussed within TMD factorization in both Drell-Yan and SIDIS processes

Summary

INTRODUCTION

The investigation of the internal structure of the nucleon remains a frontier of hadronic physics research. The inclusive cross section of SIDIS can be expressed as a convolution of nonperturbative TMD parton distribution functions and fragmentation functions and perturbatively calculated partonic cross sections. We perform a more detailed phenomenological analysis of the KM effect in SIDIS within TMD factorization and compare them with the data from the COMPASS and HERMES collaboration [16, 23, 33]. Similar phenomenological studies for asymmetries contributed by Sivers, Boer-Mulders, and Collins functions are discussed within TMD factorization in both Drell-Yan and SIDIS processes. Based on the above considerations, in this paper, we estimate the KM effect within the TMD factorization and compare the results with the HERMES and COMPASS measurements.

THEORTICAL FRAMEWORK

NUMERICAL ANALYSIS

CONCLUSION