arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1604.05239hep-ex
收藏

在sqrt(s)= 8 TeV质子-质子碰撞中寻找重共振和量子黑洞到e-mu对的轻子味破坏衰变

Search for lepton flavour violating decays of heavy resonances and quantum black holes to an e-mu pair in proton-proton collisions at sqrt(s) = 8 TeV

CMS Collaboration

摘要:

寻找衰减到一个电子和μ子的窄共振。e-mu质谱还研究了量子黑洞(QBH)的产生的非共振贡献。分析使用的数据对应的积分亮度的19.7个反femtobarns收集在质子-质子碰撞在8 TeV的质心能量与CMS检测器在大型强子对撞机。由于在选定的e-mu对的不变质谱中没有超过标准模型的物理证据,对于带电轻子味破坏理论中产生的信号,截面和分支分数的乘积的上限设定为95%置信水平。在寻找窄共振时,考虑了τ中微子在R宇称中的共振产生。对于耦合λ [132] = λ [231]= λ ′ [311] = 0.01,τ中微子在质量低于1.28 TeV时被排除,对于耦合λ [132] = λ [231] = 0.07和λ ′ [311] = 0.11,τ中微子在质量低于2.30 TeV时被排除。这些是迄今为止在高能对撞机上直接搜索的最严格的限制。此外,共振搜索的解释与Z玻色子和光子的重伙伴的模型。在TeV尺度的量子引力的牛顿常数的重整化的基础上的框架中,搜索非共振贡献的e-mu质谱排除QBH生产低于阈值质量M[th]的1.99 TeV。在调用额外维度的模型中,边界范围从一个额外维度的2.36 TeV到六个额外维度的3.63 TeV。这是对衰减到e-mu最终状态的QBH的第一次搜索。

英文摘要:

A search for narrow resonances decaying to an electron and a muon is presented. The e-mu mass spectrum is also investigated for non-resonant contributions from the production of quantum black holes (QBHs). The analysis is performed using data corresponding to an integrated luminosity of 19.7 inverse femtobarns collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC. With no evidence for physics beyond the standard model in the invariant mass spectrum of selected e-mu pairs, upper limits are set at 95% confidence level on the product of cross section and branching fraction for signals arising in theories with charged lepton flavour violation. In the search for narrow resonances, the resonant production of a tau sneutrino in R-parity violating supersymmetry is considered. The tau sneutrino is excluded for masses below 1.28 TeV for couplings lambda[132] = lambda[231] = lambda'[311] = 0.01, and below 2.30 TeV for lambda[132] = lambda[231] = 0.07 and lambda'[311] = 0.11. These are the most stringent limits to date from direct searches at high-energy colliders. In addition, the resonance searches are interpreted in terms of a model with heavy partners of the Z boson and the photon. In a framework of TeV-scale quantum gravity based on a renormalization of Newton's constant, the search for non-resonant contributions to the e-mu mass spectrum excludes QBH production below a threshold mass M[th] of 1.99 TeV. In models that invoke extra dimensions, the bounds range from 2.36 TeV for one extra dimension to 3.63 TeV for six extra dimensions. This is the first search for QBHs decaying into the e-mu final state.

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。

↑