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arXiv 0802.0949hep-ph
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最小331模型的B -> X_s γ衰变边界

Bounding the Minimal 331 Model through the Decay B -> X_s gamma

Christoph Promberger, Sebastian Schatt, Felix Schwab, Selma Uhlig

摘要:

我们在最小331模型的框架内研究了B → X_s γ衰变,考虑到新的实验和理论发展,使我们能够更新和改进现有的十年前的分析。与其他几个已经在树级从新的Z'规范玻色子修改的味道变化的观测值相比,在这种情况下,我们只有一个循环的贡献。尽管如此,这些都是有趣的,因为它们可能会被增强,并可以揭示带电规范玻色子和希格斯部门的模型。在数值上,我们发现,希格斯部门,这是很好地近似的2希格斯偶极子模型(2 HDM),占主导地位,因为规范的贡献已经非常强烈的约束。因此,对于B → X_s γ,最小331模型的信号与2 HDM模型的信号几乎相同,这使我们能够得到荷电Higgs质量的一个下界。此外,我们观察到,类似于2 HDM模型,分支分数可以相当强烈地增加小的tan β值。同时,我们发现B -> X_s γ并不影响我们在前面的分析中得到的关于稀有K和B衰变的边界。

英文摘要:

We study the decay B -> X_s gamma within the framework of the minimal 331 model, taking into account both new experimental and theoretical developments that allow us to update and improve on an existing ten year old analysis. In contrast to several other flavor changing observables that are modified already at tree level from a new Z' gauge boson, we have only one loop contributions in this case. Nevertheless, these are interesting, as they may be enhanced and can shed light on the charged gauge boson and Higgs sector of the model. Numerically, we find that the Higgs sector, which is well approximated by a 2 Higgs doublet model (2HDM), dominates, since the gauge contributions are already very strongly constrained. With respect to B -> X_s gamma, the signal of the minimal 331 model is therefore nearly identical to the 2HDM one, which allows us to obtain a lower bound on the charged Higgs mass. Further, we observe, in analogy to the 2HDM model, that the branching fraction can be rather strongly increased for small values of tan beta. Also, we find that B -> X_s gamma has no impact on the bounds obtained on rare K and B decays in an earlier analysis.

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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