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arXiv · hep-ph/9611347

Constraints on the Wr mass and CP-violation in left-right models

G. Barenboim·J. Bernabeu·J. Prades·M. Raidal
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Abstract

We update the constraints on the right-handed $W_R$ gauge boson mass, mixing angle $ζ$ with the left-handed $W_L$ gauge boson, and other parameters in general left-right symmetric models with different mechanisms of CP violation. Constraints mostly independent of any assumption on the quark sector are obtained from a re-analysis of muon decay data. Estimates of the left-right hadronic matrix elements in the neutral kaon system and their uncertainties are revised using large $N_c$ and Chiral Perturbation Theory arguments. With explicitly given assumptions on the long-distance $(ΔS=1)^2$ contributions to the $K_L-K_S$ mass difference, lower bounds on $M_{W_R}$ are obtained. With the same assumptions, one also gets strong upper bounds from the CP-violating parameter $ε_K$, for most of the parameter space of left-right models where the right-handed third family does not contribute in CP-violating quantities.

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G. Barenboim, J. Bernabeu, J. Prades, M. Raidal. 1996-11-18. Constraints on the Wr mass and CP-violation in left-right models. https://doi.org/10.1103/physrevd.55.4213

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