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arXiv 0810.2448hep-ph
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介子-重子σ项的QCD求和规则研究

QCD Sum Rules study of meson-baryon sigma terms

G. Erkol, M. Oka, G. Turan

摘要:

用量子色动力学求和规则计算了八重态和十重态重子的π-重子σ项和奇夸克凝聚。利用蒙特卡罗方法计算了外等序标量场中两个重子内插场的真空-真空跃迁矩阵元,系统地分析了求和规则和结果中的不确定性.我们提取了σ项的比值,它具有相当高的精度和最小的依赖于QCD参数。我们讨论了不确定性的来源,并评论了核子和Delta可能的奇异含量。

英文摘要:

The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of quantum chromodynamics (QCD) sum rules. We evaluate the vacuum-to-vacuum transition matrix elements of two baryon interpolating fields in an external isoscalar-scalar field and use a Monte Carlo-based approach to systematically analyze the sum rules and the uncertainties in the results. We extract the ratios of the sigma terms, which have rather high accuracy and minimal dependence on QCD parameters. We discuss the sources of uncertainties and comment on possible strangeness content of the nucleon and the Delta.

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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