OICC Press Journal of Theoretical and Applied Physics 2251-7235 11 4 2023 11 17 Proof of factorization of χcJdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$chi _{ ext{cJ}}$$end{document} production in non-equilibrium QCD at RHIC and LHC in color singlet mechanism 10.1007/s40094-017-0267-7 EN OICC Press Authors Various OICC Press Authors Journal Article 2023 11 17 AbstractRecently we have proved the factorization of NRQCD S-wave heavy quarkonium production at all orders in coupling constant. In this paper we extend this to prove the factorization of infrared divergences in χcJdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$chi _{ ext{cJ}}$$end{document} production from color singlet cc¯documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$c{ ar{c}}$$end{document} pair in non-equilibrium QCD at RHIC and LHC at all orders in coupling constant. This can be relevant to study the quark–gluon plasma at RHIC and LHC.