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

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 نشر من قبل Gabriela Barenboim
 تاريخ النشر 1996
  مجال البحث
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 تأليف G.Barenboim




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We update the constraints on the right-handed $W_R$ gauge boson mass, mixing angle $zeta$ 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 $(Delta S=1)^2$ 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 $epsilon_K$, 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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