CP Violation and 2 body B meson decays.

CP 破坏和 2 体 B 介子衰变。

• 批准号: 13640276
• 负责人: SANDA Ichiro
• 金额: $ 2.11万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640276/
• 关键词: CP Violation; Quantum mechanics; B meson; B-Physics; CP非保存; 素粒子; 対称性; B工場

In this project I studied 2 body exclusive decays of B mesons. There are over 70 such decay modes. PQCD approach was used to understand CP violations in these decays.It has been observed that Br(B→Kπ) is larger than Br(B→ππ), which indicates that there are substantial penguin contributions. As a test of PQCD these branching rations were computed to see if there is natural understanding of penguin enhancement. It is worth emphasizing that penguin annihilation amplitude can be computed in the frame work of PQCD. Thus it is possible to compute the final state strong interaction phase.The CP violation in B→Kπ and B→ππ has been computed with an estimate of uncertainty coming from computing the strong interaction phase.It is noted that only penguin diagrams contribute in B→Kψ decay. Thus by computing the branching ratio for this decay, we can critically test the ability of computing the penguin amplitudes using PQCD. It has been shown that indeed PQCD gives a sufficiently accurate estimate of the penguin amplitudes.It is know that the CP asymmetry for B→ψKs and B→Ksψ have equal CP asymmetry in the standard model. Experiments have given strong hints that these CP violations are not equal. It has been shown that it is impossible to understand the experimental results within the frame work of Super Symmetric theories.

本项目研究了B介子的两体排他衰变。有超过70种这样的衰变模式。用PQCD方法研究了这些衰变中的CP破坏，发现Br（B→Kπ）大于Br（B→ππ），这表明有相当大的企鹅贡献.作为PQCD的一个测试，这些分支率计算，看看是否有自然的理解企鹅增强。值得强调的是，企鹅湮没振幅可以在PQCD框架下计算。计算了B→Kπ和B→ππ的CP破坏，并对计算强相互作用相的不确定性进行了估计，指出只有企鹅图对B→K π衰变有贡献.因此，通过计算这种衰变的分支比，我们可以严格测试使用PQCD计算企鹅振幅的能力。PQCD确实给出了企鹅振幅的足够精确的估计，我们知道在标准模型中B→ Ks的CP不对称性与B→Ks的CP不对称性相等。实验已经给出了强有力的暗示，这些CP破坏是不相等的。已经表明，在超对称理论的框架内理解实验结果是不可能的。

项目成果

A. I. Sanda 他2名: "PENGUIN ENHANCEMENT AND B --->K PI DECAYS IN PERTURBATIVE QCD"Phys. Rev.. D63. 054008 (2001)

A. I. Sanda 和其他 2 人：“微扰 QCD 中的企鹅增强和 B --->K PI 衰减”Phys. Rev. 054008 (2001)。

A.I.Sanda, Kazumasa Ukai: "HOW WELL CAN WE PREDICT CP ASYMMETRY IN B→_<ππ>, _πK DECAYS?"Prog Theor. Phys.. 107. 421-432 (2002)

A.I.Sanda、Kazumasa Ukai：“我们如何预测 B→_<ππ>、_πK 衰变中的 CP 不对称？”Prog Theor.. 107. 421-432 (2002)

B→Kη(η') DECAY IN PERTURBATIVE QCD.

B→Kη(η) 微扰 QCD 衰变。

• 发表时间: 2002
• 期刊: Phys.Lett. 525
• 作者: E.Kou;A.I.Sanda
• 通讯作者: A.I.Sanda

Yong-Yeon Keum, T.Kurimoto, Hsiang Nan Li, Cai-Dan Lu, A.I.Sanda: "NONFACTORIZABLE CONTRIBUTIONS TO B ---> D**(*) M DECAYS"Phys.Rev.D. (発表予定). (2004)

Yong-Yeon Keum、T.Kurimoto、Hsiang Nan Li、Cai-Dan Lu、A.I.Sanda：“不可因子化的贡献 B ---> D**(*) M DECAYS”Phys.Rev.D（待提交） （2004）

HOW WELL CAN WE PREDICT CP ASYMMETRY IN B→ππ, πK DECAYS?

我们如何准确地预测 B→ππ、πK 衰变中的 CP 不对称性？

• 发表时间: 2002
• 期刊: Prog Theor.Phys. 107
• 作者: A.I.Sanda;Kazumasa Ukai
• 通讯作者: Kazumasa Ukai