Lepton non-universality at LEP and charged Higgs

Abstract

A recent analysis of the LEP data shows an interesting deviation from lepton universality in W boson decays. An excess at the level of 2.8 sigma is found in the tau mode branching ratio with respect to the other two modes. It is suggested that this seeming lepton non-universality might stem from pair production of charged Higgs bosons almost degenerate with W, that preferentially decay to heavy fermions. It is shown that the deviation can be reduced to 1.4 sigma in two Higgs doublet model I without any conflict with the existing direct or indirect constraints. This conclusion is largely independent of tan beta, the ratio of Higgs vacuum expectation values. This scenario can be tested at the forthcoming international linear collider.

16 pages, published version with minor changes

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Cited by in corpus (13)

• Theory and phenomenology of two-Higgs-doublet models
• Flavour physics of leptons and dipole moments
• Status of the Charged Higgs Boson in Two Higgs Doublet Models
• Let there be light from a second light Higgs doublet
• Scalar doublet models confront $\tau$ and $b$ anomalies
• U(2)^5 flavor symmetry and lepton universality violation in W -> tau nu_tau
• Masses of physical scalars in two Higgs doublet models
• Alignment, reverse alignment, and wrong sign Yukawa couplings in two Higgs doublet models
• LHC explores what LEP hinted at: CP-violating type-I 2HDM
• Trilepton Signatures of Light Charged and CP-odd Higgs Bosons in Top Quark Decays
• On a Latent Structure of Lepton Universality
• Radiative $B_c$ meson decays $B_c\to \gamma u\bar{d}$
• Is there really a $W\to \tau \nu$ puzzle?