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arXiv 1003.3230hep-ph
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T-宇称和非T-宇称最小Higgs模型的壳层上$WWγ$顶点

On-shell $WWγ$ vertex in the T-Parity and non T-Parity Littlest Higgs model

A. Moyotl, G. Tavares-Velasco

摘要:

在T宇称和非T宇称的最小希格斯模型(LHM)中计算了$W$玻色子的静态电磁性质,其中$Δκ$和$ΔQ$项的数量级为$(v/f)^4$,$v$为标准模型(SM)的真空期望值,$f$为整体对称性破缺的标度.新的重粒子的虚效应和对SM顶点的新修正都有贡献,它们依赖于混合参数$c$,并随着$f$的增加而迅速减小。根据$c$的值,对$Δκ$和$ΔQ$的部分贡献可以相长或相消地相加。$(v/f)^4$阶的项是次显性的,但是它们可以建设性地相加,并且可以增强$f < 1$ TeV的$W$形状因子。一般来说,$W$形状因子的大小在没有T奇偶校验的LHM中被非常抑制,因为来自电弱精确测量的尺度$f$上的约束非常严格。具有T-宇称的LHM没有这样的约束,它允许$W$形状因子的值类似于在其他弱耦合SM扩展中发现的值,尽管它们超出了LHC未来测量的预期灵敏度。我们还讨论了由于强相互作用的紫外完成的左手材料所产生的相互作用,有一些增强的可能性。

英文摘要:

The static electromagnetic properties of the $W$ boson, $Δκ$ and $ΔQ$, are calculated in the T-parity and non T-parity littlest Higgs model (LHM) including terms up to the order of $(v/f)^4$, with $v$ the standard model (SM) vacuum expectation value and $f$ the scale of the global symmetry breaking. There are contributions from the virtual effects of the new heavy particles and also from the new corrections to the SM vertices, which depend on the mixing parameter $c$ and decrease quickly as $f$ increases. Depending on the value of $c$, the partial contributions to $Δκ$ and $ΔQ$ can add constructively or destructively. The terms of the order of $(v/f)^4$ are subdominant but they can add constructively and can enhance the $W$ form factors for $f < 1$ TeV. In general the size of the $W$ form factors is very suppressed in the LHM without T-parity as the constraints on the scale $f$ from electroweak precision measurements are very tight. The LHM with T-parity has no such constraints and it allows for values of $W$ form factors similar to those found in other weakly coupled SM extensions, though they are out of the expected sensitivity of future measurements at the LHC. We also discuss the possibility that there is some enhancement due to the interactions arising from the strongly interacting ultraviolet completion of the LHM.

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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