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arXiv · 1207.4894

LHC sensitivity to lepton flavour violating Z boson decays

Sacha Davidson·Sylvain Lacroix·Patrice Verdier
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Abstract

We estimate that the LHC could set bounds BR(Z -> mu^\pm e^\mp) < 4.1 * 10^{-7} and BR(Z -> tau^\pm mu^\mp)< 3.5 * 10^{-6} (at 95% C.L.) with 20 inverse fb of data at 8 TeV. A similar sensitivity can be anticipated for Z -> tau^\pm e^\mp, because we consider leptonic tau decays such that Z -> tau^+ mu^- gives e^+ \mu^- +$ invisibles. These limits can be compared to the LEP1 bounds of order 10^{-5} to 10^{-6}. Such collider searches are sensitive to a flavour-changing effective Z coupling which is energy dependent, so are complementary to bounds obtained from tau to 3mu and mu to 3e.

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Sacha Davidson, Sylvain Lacroix, Patrice Verdier. 2012-07-20. LHC sensitivity to lepton flavour violating Z boson decays. https://doi.org/10.1007/jhep09(2012)092

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