Measuring B -> tau nu and B_c -> tau nu at the Z peak

Abstract

The measurement of B->tau nu at the B factories provides important constraints on the parameter tan beta/m_H^+- in the context of models with two Higgs doublets. Limits on this decay from e+e- collisions at the Z peak were sensitive to the sum of B->tau nu and B_c->tau nu. Due to the possibly sizeable contribution from B_c->tau nu we suggest that a signal for this combination might be observed if the LEP L3 Collaboration used their total data of ~3.6 10^6 hadronic decays of the Z boson. Moreover, we point out that a future Linear Collider operating at the Z peak (Giga Z option) could constrain tan beta/m_H^+- from the sum of these processes with a precision comparable to that anticipated at proposed high luminosity B factories from B-> tau nu alone.

12 pages, 4 figures. Value of Vub updated, references added. Version to appear in PRD

References in corpus (13)

• Estimate of BR(B -> X_s gamma) at O(alpha_s^2)
• NNLO QCD corrections to the B -> X_s gamma matrix elements using interpolation in m_c
• Hints of large tan(beta) in flavour physics
• Updated Constraints from B Physics on the MSSM and the NMSSM
• Flavour physics at large tan(beta) with a Bino-like LSP
• The Supersymmetric Parameter Space in Light of B-physics Observables and Electroweak Precision Data
• B-Meson Observables in the Maximally CP-Violating MSSM with Minimal Flavour Violation
• Charged Higgs on $B^{-}\to \tau {\bar{\nu }}_{\tau }$ and $\bar{B}\to P(V)\ell {\bar{\nu }}_{\ell }$
• Effect of H^\pm on B^\pm\to τ^\pmν_τand D^\pm_s\to μ^\pmν_μ,τ^\pmν_τ
• Light charged Higgs at the beginning of the LHC era
• Challenging SO(10) SUSY GUTs with family symmetries through FCNC processes
• Challenges for MSSM Higgs searches at Hadron Colliders
• Study of the exclusive $b\to u{\ell }^{-}{\bar{\nu }}_{\ell }$ decays in the MSSM with and without R-parity violation

Cited by in corpus (4)

• Constraint on the branching ratio of B_c \to tau nu from LEP1 and consequences for R(D(*)) anomaly
• Charged Higgs phenomenology in the lepton-specific two Higgs doublet model
• Analysis of $B_c\to \tau {\nu }_{\tau }$ at CEPC
• Search for $B_c^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ decays and measurement of the branching fraction ratio $\mathcal{B}(B_c^{+}\to \psi (2S){\pi }^{+})/\mathcal{B}(B_c^{+}\to J/\psi {\pi }^{+})$