论文标题
关于LHC的主要中微子衰减中中微子衰变的螺旋性反转的定量研究
A quantitative study on helicity inversion in Majorana neutrino decays at the LHC
论文作者
论文摘要
我们报告了对LHC流程中螺旋倒的影响的分析和数值调查，该过程不保留Lepton Number $（L）$。作为一个案例研究，我们专注于Majorana Neutminos $（n）$（通过现象学类型型模型）的生产和衰减。使用蒙特卡洛事件生成器\ texttt {madgraph5 \ _amc@nlo}与\ texttt {heafeN}模型库结合使用，我们执行精确的矩阵元素（me）计算，而无需狭窄的宽度近似。尽管MES中明确出现了螺旋倒置，但我们报告说，$ 1 \ to4 $ $ 1 \ to4 $和$ 2 \ to4 $流程的均无抑制$ l $ a $ violation collider colleverables。我们将这种不一致性归因于4-Momenta的不同尺度和MES和Squared MES的4-Momenta，当$ N $以小宽度限制以小宽度限制时，在后者中发生了精确的取消。在外壳制度中，可以出现$ L $ $ $ $ $ $ $ $的总抑制 /增强。讨论了对其他中微子质量模型的影响。
We report an analytical and numerical investigation into the impact of helicity inversion in LHC processes that do not conserve lepton number $(L)$. As a case study, we focus on the production and decay of Majorana neutrinos $(N)$ through on- and off-shell $W$ bosons in the Phenomenological Type I Seesaw model. Using the Monte Carlo event generator \texttt{MadGraph5\_aMC@NLO} in conjunction with the \texttt{HeavyN} model libraries, we perform exact matrix element (ME) computations without the narrow width approximation. Despite helicity inversion appearing explicitly in MEs, we report the absence of helicity suppression of $L$-violating collider observables for $1\to4$ and $2\to4$ processes that are dominated by resonant $N$ production. We attribute this incongruity to the different scalings of 4-momenta and squared 4-momenta in MEs and squared MEs, with exact cancelations occurring in the latter when $N$ goes on-shell in the small-width limit. In off-shell regimes, total suppression / enhancement of $L$ violation can emerge. Implications for other neutrino mass models are discussed.
