Tadashi Yoshikawa

Measurement of the lifetime difference of Bd mesons: possible and worthwhile?

Abstract We estimate the decay width difference ΔΓd/Γd in the Bd system including 1/mb contributions and part of the next-to-leading order QCD corrections, and find it to be around 0.3%. We explicitly show that the time measurements of an untagged Bd decaying to a single final state isotropically can only be sensitive to quadratic terms in ΔΓd/Γd, and hence the use of at least two different final states is desired. We discuss such pairs of candidate decay channels for the final states and explore the feasibility of a ΔΓd/Γd measurement through them. The measurement of ΔΓd would be essential for an accurate measurement of sin(2β) at the LHC. The nonzero width difference can also be used to identify new physics effects and to resolve a twofold discrete ambiguity in the Bd– B d mixing phase. We also derive an upper bound on the value of ΔΓd/Γd in the presence of new physics, and point out some differences in the phenomenology of width differences in the Bs and Bd systems.

Majorana mass zeros from Higgs triplet vacuum expectation values without a Majoron problem

It is shown how to obtain recently-proposed two-zero Majorana mass textures in models with three Higgs triplets with small VEVs and a sufficiently massive triplet Majoron by using abelian discrete symmetries. It is briefly discussed how in SU(5) grand unification where the triplets occur in {\bf 15}s the neutrino textures can be related to up- and down- quark mass textures.

Zee model confronts SNO data

We reexamine the solution of the minimal Zee model by comparing with the data of the SNO experiment, and conclude that the model is strongly disfavored but not yet excluded by the observations. Two extensions of the Zee model are briefly discussed both of which introduce additional freedom and can accommodate the data.

Longitudinal polarization asymmetry of leptons in pure leptonic B decays

The longitudinal polarization asymmetry of leptons in

Measurement of the width difference of Bd mesons

{B}_{q}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}

Large electroweak penguin contribution in B{yields}K{pi} and {pi}{pi} decay modes

(q=d,s

Large electroweak penguin contribution inB→Kπandππdecay modes

and

Sufficiently Small

l=e,\ensuremath{\mu},\ensuremath{\tau})

\bar{\theta}

decays is investigated. The analysis is done in a general manner by using the effective operator approach. It is shown that the longitudinal polarization asymmetry should provide a direct search for the scalar and pseudoscalar type interactions that are induced in all variants of Higgs-doublet models.