Complete study on polarization of γ(nS) hadroproduction at QCD next-to-leading order  

作　　者：Yu Feng Bin Gong Chao-Hsi Chang Jian-Xiong Wang 冯宇;龚斌;张肇西;王建雄(Department of Physics,College of Basic Medical Sciences,Army Medical University,Chongqing 400038,China;CAS Key Laboratory of Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190,China;Institute of High Energy Physics,Chinese Academy of Sciences,P.O.Box 918(4),Beijing 100049,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]Department of Physics,College of Basic Medical Sciences,Army Medical University,Chongqing 400038,China [2]CAS Key Laboratory of Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of Sciences,Beijing 100190,China [3]Institute of High Energy Physics,Chinese Academy of Sciences,P.O.Box 918(4),Beijing 100049,China [4]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Chinese Physics C》2021年第1期187-195,共9页中国物理C（英文版）

基　　金：supported in part by the National Natural Science Foundation of China (11905292,11535002, 11675239, 11745006, 11821505, 11947302, 11975242);supported by Key Research Program of Frontier Sciences,CAS,Grant No. QYZDYSSW-SYS006 and Y7292610K1。

摘　　要：By applying the nonrelativistic quantum chromodynamics factorization formalism toγ(1S.2S,3S)hadroproduction,a complete analysis of the polarization parametersλθ,λθФ、andλФfor the production is presented at QCD next-to-leading order.With the long-distance matrix elements extracted from experimental data for the production rate and polarization parameterλθofγhadroproduction,our results provide a good description of the measured parametersλθФandλФin both the helicity and Collins-Soper frames.In our calculations,the frame invariant parameterλ^-is consistent in the two frames.Finally,we mention that there are discrepancies between the available experimental data and corresponding theoretical predictions forλ^-.

关 键 词：heavy quarkonium POLARIZATION NRQCD 

分 类 号：O572.243[理学—粒子物理与原子核物理]