Twist-4 contributions to e<SUP>+</SUP>e- → ΩX process

作     者：Yang, Weihua 

作者机构：Yan Tai Univ Coll Nucl Equipment & Nucl Engn Yantai 264005 Peoples R China 

出 版 物：《NUCLEAR PHYSICS A》 (核物理学，A辑)

年 卷 期：2020年第997卷

页      面：121729-121729页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：National Laboratory Foundation 

主　　题：Twist-4 Annihilation process Fragmentation functions 

摘      要：The description of particles with spin in high energy reaction can be attained by using a spin density matrix. In this paper we introduce the spin density matrix for spin-3/2 particles. With this matrix, we present the complete twist-4 results for the e(+)e- - Omega X at the tree level of perturbative quantum chromodynamics. The calculations are carried out by applying the collinear expansion. In the collinear expansion formalism the multiple gluon scattering is taken into account and gauge links are obtained systematically and automatically. We present the complete results for structure functions and the polarizations of the produced hadron in terms of gauge invariant fragmentation functions up to twist-4. We obtain 28 structure functions, among them 8 are leading twist, 12 are twist-3, 4 are twist-4 and the others do not correspond to fragmentation functions. We also obtain 3 longitudinal and 6 transverse polarizations. For the complete twist-4 calculation, the four-quark correlator contributions are also considered in this paper. (C) 2020 Elsevier B.V. All rights reserved.