【摘 要】
：
用QCD求和规则计算了π介子和K介子的两个twist-3分布振幅的归一化常数mp0π和mp0K. 与运动方程的要求不同, 计算结果表明(把求和规则微扰部分的αs修正考虑之后),mp0π＝1.00
【机 构】
：
科学院高能物理研究所,国高等科技中心
论文部分内容阅读
用QCD求和规则计算了π介子和K介子的两个twist-3分布振幅的归一化常数mp0π和mp0K. 与运动方程的要求不同, 计算结果表明(把求和规则微扰部分的αs修正考虑之后),mp0π＝1.00±0.17GeV, mp0K＝1.46±0.23GeV. 应该指出的是, 它们与运动方程给出的结果相比要小不少.比如π介子的情形, QCD求和规则给出的上述结果约是运动方程要求的值的50%左右. 在exclusive的一些过程中, 人们发现, 一直到Q2较大(2-40GeV2)的区域, 本应受到抑止的非首要的(比如, non-leading twist的贡献) 贡献还可以跟首要的贡献(比如, leading twist的贡献)相比, 甚至可以超过. 这是难以相信的. 而较小的归一化常数将有助于弱化这个矛盾.计算结果支持这一点.
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