高能电子-质子碰撞中重夸克偶素的遍举产生

Exclusive quarkonium production in high energy e-p collision

夸克偶素产生和衰变研究对深入了解量子色动力学(QCD),研究夸克偶素,甚至探索其他高能相互作用和微观粒子的性质都具有重要意义。计算重夸克偶素在电子-质子高能碰撞中的遍举产生,发现它能为探究质子部分子的分布结构,验证非相对论量子色动力学,精确检验微扰QCD的适用范围提供有益的帮助。在共线因子化框架下,计算给出QCD领头阶重夸克偶素遍举产生的振幅和截面的解析结果,并以HERA实验为例,唯象分析HERA实验条件下J/ψ和Υ遍举产生截面随Q2和Wγp的变化规律,与实验结果进行比对。还讨论了能标和重夸克质量不确定性带来的理论分析误差。

Quarkonium production and decay play an important role in the investigations of quantum chromodynamics(QCD) and the properties of quarkonium and other high energy interactions and particles. In this work, we calculate the heavy quarkonium exclusive production in electron-proton scattering, and find that it may deepen our understanding of the parton structure of nucleon, testify the non-relativistic QCD(NRQCD) formalism, and specify the applicability scope of perturbative QCD(pQCD). Within the collinear factorization framework, we analytically calculate the amplitude and cross section of quarkonium exclusive production at the leading order of pQCD. Taking the HERA experiment of photoproduction and electroproduction as an example, we analyze phenomenologically the cross-section dependence of J/ψ and Υ production on Q2 and Wγp. We estimate also the theoretical errors induced by the energy-scale and quark-mass uncertainties.