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arXiv 1401.0923hep-phnucl-th
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对撞机能量下的重夸克偶素产生:因子分解和演化

Heavy Quarkonium Production at Collider Energies: Factorization and Evolution

Zhong-Bo Kang, Yan-Qing Ma, Jian-Wei Qiu, George Sterman

摘要:

本文给出了对撞机能量下大横动量重夸克偶素$p_T$的包含产生的因式分解形式,包括$p_T$中的主导幂次(LP)和次主导幂次(NLP)行为.我们证明,LP和NLP的贡献可以因式分解的微扰计算的短距离部分子系数函数和普遍的非微扰碎裂功能,并推导出演化方程所隐含的因式分解。我们确定投影运营商的所有渠道的因式分解的LP和NLP红外安全的短距离部分子硬的部分,和相应的运营商定义的碎裂功能。对于NLP,我们专注于涉及产生重夸克对的贡献,这是产生重夸克偶素的必要条件。我们评估了所有相关碎片函数的第一个非平凡阶演化核,并讨论了NLP贡献的作用。

英文摘要:

We present a factorization formalism for inclusive production of heavy quarkonia of large transverse momentum, $p_T$ at collider energies, including both leading power (LP) and next-to-leading power (NLP) behavior in $p_T$. We demonstrate that both LP and NLP contributions can be factorized in terms of perturbatively calculable short-distance partonic coefficient functions and universal non-perturbative fragmentation functions, and derive the evolution equations that are implied by the factorization. We identify projection operators for all channels of the factorized LP and NLP infrared safe short-distance partonic hard parts, and corresponding operator definitions of fragmentation functions. For the NLP, we focus on the contributions involving the production of a heavy quark pair, a necessary condition for producing a heavy quarkonium. We evaluate the first non-trivial order of evolution kernels for all relevant fragmentation functions, and discuss the role of NLP contributions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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