论文标题
在$ \ sqrt {s} = $ 13 tev中搜索质子 - 普罗顿碰撞中带有位移顶点的长期重型中性钩子
Search for long-lived heavy neutral leptons with displaced vertices in proton-proton collisions at $\sqrt{s} =$ 13 TeV
论文作者
论文摘要
在最终状态下，使用CMS实验收集的Proton-Proton碰撞数据在最终状态下，在最终状态下，在最终状态下搜索重中性瘦素（HNL），即右手狄拉克或主要中微子。数据对应于138 fb $^{ - 1} $的集成光度。 HNL可以通过与标准型号中微子$ν$混合而产生。对于hnl质量（$ \ lt $ 20 GEV）和HNL- $ν$混合参数的平方（10 $^{ - 7} $ - 10 $ -10 $^{ - 2} $），这些颗粒的衰减长度可以很大，因此HNL衰减的次级山脉可以与CMS Silicon silicon silicon Resolved resolved sillecons sillecons silicon silicon silicon silicon。选定的最终状态由一个从主要的质子 - 普罗顿碰撞顶点出现的轻子量和两个形成流离失所的次级顶点的瘦素组成。未观察到与标准模型期望的显着偏差，并且在HNL质量和耦合强度参数上获得了约束，在质量范围1-20 GEV中排除了先前未开发的参数空间区域和平方混合参数值低至10 $^{-7} $。
A search for heavy neutral leptons (HNLs), the right-handed Dirac or Majorana neutrinos, is performed in final states with three charged leptons (electrons or muons) using proton-proton collision data collected by the CMS experiment at $\sqrt{s} =$ 13 TeV at the CERN LHC. The data correspond to an integrated luminosity of 138 fb$^{-1}$. The HNLs could be produced through mixing with standard model neutrinos $ν$. For small values of the HNL mass ($\lt$ 20 GeV) and the square of the HNL-$ν$ mixing parameter (10$^{-7}$-10$^{-2}$), the decay length of these particles can be large enough so that the secondary vertex of the HNL decay can be resolved with the CMS silicon tracker. The selected final state consists of one lepton emerging from the primary proton-proton collision vertex, and two leptons forming a displaced, secondary vertex. No significant deviations from the standard model expectations are observed, and constraints are obtained on the HNL mass and coupling strength parameters, excluding previously unexplored regions of parameter space in the mass range 1-20 GeV and squared mixing parameter values as low as 10$^{-7}$.
