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arXiv 1306.1534hep-ph
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天然SUSY是天然的吗?

Is Natural SUSY Natural?

Edward Hardy

摘要:

我们研究了微调相关的“自然超对称”频谱停止,RG运行后,显着轻于前两代sfermions和胶子。特别是,我们强调,这种调整应测量相对于在假设的UV边界的重整化组流的参数是独立的,并提高以前的近似表达式的准确性。结果发现,如果运行开始于$10^{16}~\rm{GeV}$ $\left(10^5~\rm{GeV}\right)$,降低低于$0.75$ $\left(0.4\right)$的弱标度Majorana胶子质量的UV停止质量不提高整体微调的理论。相比之下,在不引入额外调谐的情况下,有可能将前两代sfermion质量提高到LHC无法达到的程度。运行后,参数空间的区域有利于自然性和符合LHC边界通常有1.5 TeV(0.75 TeV)的IR停止质量,并微调至少400(50)高(低)规模调解。我们还研究了狄拉克胶子理论的微调。这使得大量的分离的胶子和sfermion质量,无论调解的规模,导致相对较低的微调为50阶。因此,可行的模型仍然可以青睐光停止,但这需要额外的结构超出MSSM字段内容。

英文摘要:

We study the fine tuning associated to a `Natural Supersymmetry' spectrum with stops, after RG running, significantly lighter than the first two generation sfermions and the gluino. In particular, we emphasise that this tuning should be measured with respect to the parameters taken to be independent at the assumed UV boundary of the renormalisation group flow, and improve the accuracy of previous approximate expressions. It is found that, if running begins at $10^{16}~\rm{GeV}$ $\left(10^5~\rm{GeV}\right)$, decreasing the UV stop mass below $0.75$ $\left(0.4\right)$ of the weak scale Majorana gluino mass does not improve the overall fine tuning of the theory. In contrast, it is possible to raise the first two generation sfermion masses out of LHC reach without introducing additional tuning. After running, regions of parameter space favoured by naturalness and consistent with LHC bounds typically have IR stop masses of order 1.5 TeV (0.75 TeV), and fine tuning of at least 400 (50) for high (low) scale mediation. We also study the fine tuning of theories with Dirac gluinos. These allow for substantial separation of the gluino and sfermion masses and, regardless of the scale of mediation, lead to relatively low fine tuning of order 50. Hence viable models can still favour light stops, but this requires extra structure beyond the MSSM field content.

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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