Rare K and B Decays in a warped extra dimension with custodial protection
Rare K and B Decays in a warped extra dimension with custodial protection
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DOI：
10.1088/1126-6708/2009/03/108
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发表时间：
2009-03-01
影响因子：
5.4
通讯作者：
Gori, Stefania
中科院分区：
文献类型：
--
作者：
Blanke, Monika;Buras, Andrzej J.;Gori, Stefania
我们在一个有监护保护的扭曲的额外维模型中对稀有的K和B介子衰变进行了完整的研究。（对角和非对角）Zd（L）（i）（d）对棒（j）（L）耦合，包括K+ -> pi（+）nu（nu）对棒，K-L-> pi（0）nu（nu）对棒，K-L -> pi（0）1 + 1（-），K-L -> mu（+）mu（-），B-s，B-d -> mu（+）mu（-），B -> K nu（nu），B -> K*nu（nu），B -> X-s，X-d nu（nu）。在这个模型中，除了标准模型的单圈贡献外，这些过程还接收来自Z玻色子和新的重电弱规范玻色子的树级贡献。我们分析了所有这些贡献，原来是占主导地位的树级Z玻色子交流右手耦合向下型夸克。通过对我们最近分析的Delta F = 2跃迁的所有约束条件进行拟合，并对所有夸克质量和CKM混合参数进行拟合，我们发现稀有K衰变的一些分支比可能与SM的预测有很大的不同，而稀有B衰变的相应影响是适度的，这主要是由于保管保护在B衰变中比在K衰变中更有效。为了减少参数的依赖性，我们研究的K系统内，在B系统，特别是在K和B系统之间的各种观测之间的相关性，也之间的Δ F = 2和Δ F = 1的观测。这些相关性允许在这种新的物理场景和具有最小味道违反的模型或具有T宇称的最小希格斯模型之间进行明确区分，并且可以为未来的实验提供机会来确认或排除该模型。我们展示了如果不存在Zd（L）（i）（d）对bar（j）（L）耦合的监护保护，我们的结果将如何变化。在罕见的B衰变的情况下，修改是壮观的。
We present a complete study of rare K and B meson decays in a warped extra dimensional model with a custodial protection of (both diagonal and non-diagonal) Zd(L)(i)(d) over bar (j)(L) couplings, including K+ -> pi(+)nu(nu) over bar, K-L -> pi(0)nu(nu) over bar, K-L -> pi(0)l+l(-), K-L -> mu(+)mu(-), B-s,B-d -> mu(+)mu(-), B -> K nu(nu) over bar, B -> K*nu(nu) over bar and B -> X-s,X-d nu(nu) over bar. In this model in addition to Standard Model one loop contributions these processes receive tree level contributions from the Z boson and the new heavy electroweak gauge bosons. We analyse all these contributions that turn out to be dominated by tree level Z boson exchanges governed by right-handed couplings to down-type quarks. Imposing all existing constraints from Delta F = 2 transitions analysed by us recently and fitting all quark masses and CKM mixing parameters we find that a number of branching ratios for rare K decays can differ significantly from the SM predictions, while the corresponding effects in rare B decays are modest, dominantly due to the custodial protection being more effective in B decays than in K decays. In order to reduce the parameter dependence we study correlations between various observables within the K system, within the B system and in particular between K and B systems, and also between Delta F = 2 and Delta F = 1 observables. These correlations allow for a clear distinction between this new physics scenario and models with minimal flavour violation or the Littlest Higgs Model with T-parity, and could give an opportunity to future experiments to confirm or rule out the model. We show how our results would change if the custodial protection of Zd(L)(i)(d) over bar (j)(L) couplings was absent. In the case of rare B decays the modifications are spectacular.