中文

用R宇称破坏超对称解释大的顶夸克对前后不对称性

高能物理 - 唯象学 2013-05-30 v5 高能物理 - 实验

摘要

我们提出一种超对称解释,用于解释CDF和D0实验测量到的顶夸克对产生中反常高的前后不对称性。假设该不对称性源于t道交换一个右手底标量夸克(sbottom),该粒子与d_R和t_R耦合,正如R宇称破坏的最小超对称标准模型中所存在的。我们表明,对于底标量夸克质量在300到1200 GeV之间、大Yukawa耦合>2.2的情况,所有Tevatron和LHC实验的t\={t}约束均可满足,从而产生高达0.18的A_{FB}。对LHC电荷不对称性参数的非标准模型贡献为ΔA_C^y=0.017-0.045,足够小以与当前测量一致,但非零且为正,使得未来在20 fb^-1内可在LHC上得到确认。还预测了对LHC t\={t}产生截面的微小额外贡献,可提供进一步检验。我们估计,如果t\={t}截面的测量结果恰好以标准模型预测为中心,则10 fb^-1的LHC亮度足以在95%置信水平上排除该提议。

关键词

引用

@article{arxiv.1205.5170,
  title  = {R-Parity Violating Supersymmetry Explanation for Large t tbar Forward-Backward Asymmetry},
  author = {B. C. Allanach and K. Sridhar},
  journal= {arXiv preprint arXiv:1205.5170},
  year   = {2013}
}

备注

5 pages, 2 figures, v2 has added comments and references and increased statistics, leading to more accurate numerical predictions. v3 has typos in Fig 1 fixed: arrow directions and t and tbar labels. v4 has added discussion and corrections to Eq 4. v5 has luminosity predictions, additional checks and small numerical changes