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arXiv 0901.4704hep-ph
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具有监护保护的扭曲额外维模型中的味破坏模式

Patterns of Flavour Violation in a Warped Extra Dimensional Model with Custodial Protection

Stefania Gori

摘要:

我们提出了一个特殊的扭曲额外维模型,其中味道对角和味道非对角Z玻色子耦合到左手下夸克是由保管对称性P_LR保护的。在简要介绍了该模型及其主要理论动机之后,我们对稀有K和B介子衰变进行了全面的研究,包括K +--> pi + nu anti-nu,K_L--> pi 0 nu anti-nu,B_{s,d}--> mu + mu-和B_{s,d}--> X_{s,d} nu anti-nu.特别地,我们将模型的参数空间限制在适合所有夸克质量、CKM混合参数和所有测量的Delta F = 2观测量的子空间,使Kaluza-Klein标度保持在LHC(~(2 - 3)TeV)的范围内。在那里,我们表明,除了标准模型(SM)的一个循环的贡献,占主导地位的新的物理贡献的罕见的衰变的K和B_{s,d}介子是树级交换的SM的Z玻色子的右手耦合下型夸克。为了减少参数依赖性,我们研究了B和K介子不同分支比之间的关联以及Delta F = 1和Delta F = 2观测量之间的关联。我们发现的模式可以将这种新的物理场景与SM区分开来,并为未来的实验提供机会来确认或排除模型。

英文摘要:

We present a particular warped extra dimensional model, where the flavour diagonal and flavour non-diagonal Z boson couplings to left-handed down quarks are protected by the custodial symmetry P_LR. After a brief introduction of the model and of its main theoretical motivations, we present a complete study of rare K and B meson decays, including K+ --> pi+ nu anti-nu, K_L --> pi0 nu anti-nu, B_{s,d} --> mu+ mu- and B_{s,d} --> X_{s,d} nu anti-nu. In particular we restrict the parameter space of the model to the subspace which fits all quark masses, CKM mixing parameters and all the measured Delta F=2 observables, keeping the Kaluza-Klein scale in the reach of LHC (~(2-3)TeV). There we show that, in addition to the one loop contribution of the Standard Model (SM), the dominating new physics contribution to the rare decays of K and B_{s,d} mesons is the tree level exchange of the Z boson of the SM governed by right-handed couplings to down-type quarks. In order to reduce the parameter dependence, we study correlations between various branching ratios of B and K mesons and between Delta F=1 and Delta F=2 observables. The patterns that we find allow to distinguish this new physics scenario from the SM and can offer an opportunity to future experiments to confirm or rule out the model.

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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