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تسجيل مستخدم جديدCorrelating Non-Resonant Di-Electron Searches at the LHC to the Cabibbo-Angle Anomaly and Lepton Flavour Universality Violation
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In addition to the existing strong indications for lepton flavour university violation (LFUV) in low energy precision experiments, CMS recently released an analysis of non-resonant di-lepton pairs which could constitute the first sign of LFUV in high-energy LHC searches. In this article we show that the Cabibbo angle anomaly, an (apparent) violation of first row and column CKM unitarity with $approx3,sigma$ significance, and the CMS result can be correlated and commonly explained in a model independent way by the operator $[Q_{ell q}^{(3)}]_{1111} = (bar{ell}_1gamma^{mu}sigma^Iell_1)(bar{q}_1gamma_{mu}sigma^Iq_1)$. This is possible without violating the bounds from the non-resonant di-lepton search of ATLAS (which interestingly also observed slightly more events than expected in the electron channel) nor from $R(pi)=pi tomu u/pi to e u$. We find a combined preference for the new physics hypothesis of $4.5,sigma$ and predict $1.0004<R(pi)<1.0009$ (95%~CL) which can be tested in the near future with the forthcoming results of the PEN experiment.
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