Search

A phenomenological analysis of D → Kn and D+s → KK decays including both Cabibbo-favored and doubly-Cabibbo-suppressed modes have been presented by employing the present experimental data. SU(3) symmetry breaking effects from the decay constants and form factors have been taken into account in the analysis. Three asymmetries, R(D°), R(D+), and R(D+s), which are generated through interference between Cabbibo-favored and doubly-Cabibbo-suppressed decays, are estimated. Theoretical results agree well with the current measurements. [ABSTRACT FROM AUTHOR]

Motivated by the experimental study of J/ψ → γ+ invisible decay by the CLEO Collaboration, we analyze the process J/ψ → γvv, as the standard model background for this invisible decay, at the lowest order. Our investigation shows that Br(J/ψ → γvv) is far below the present experimental upper limit on the branching ratio of J/ψ → γ+ invisible, which indicates that some interesting room for new physics in this channel might be expected. We also present a similar analysis of the ηc → γvv decay. [ABSTRACT FROM AUTHOR]

Using the Higgs boson mass mh -- 125 GeV, the radiative Higgs decays h yvfii with i/t = ve, v, and vT are analyzed in the standard model. Our calculation shows that the inclusive width of these processes, i.e., the sum of r(h -* yvfit) for vt = ue, v, uT, is 1.41 keV, which is about 15% of T(h -»• yy). Therefore, the observation of these channels in future precise experiments may provide some useful information on the Higgs physics in both the standard model and its possible extensions. [ABSTRACT FROM AUTHOR]

Based on experimental data by the Belle Collaboration, we present a phenomenological analysis of the angular distributions in τ- → KSπ-ντ decay. Our study shows that the angular analysis could lead to some interesting observables, and the future experimental investigation of these observables might be very helpful in revealing the nature of the scalar components of the decay. New physics contributions from the two-Higgs-doublet model to this decay have also been examined. [ABSTRACT FROM AUTHOR]

We study the long-distance contribution to Bs → μ+μ- decay, which is generated by the two-photon intermediate state via the Bs → γ * γ ∗ → μ+μ- transition. It is found that the dispersive two-photon amplitude can interfere with the dominant short-distance amplitude, which gives rise to new theoretical uncertainty in the branching ratio of Bs → μ+μ-. Our analysis shows that, by taking into account present experimental constraints, this uncertainty could be up to the same order of magnitude as some theoretical uncertainties of B (Bs → μ+μ-) given in the past literature. Future precise studies of the double radiative Bs → γ γ decay, both experimentally and theoretically, may help to reduce the uncertainty. This novel effect has never been examined in Bs → μ+μ- decay. [ABSTRACT FROM AUTHOR]

A search for the invisible decays of ω and ϕ mesons in J/ψ→ω(ϕ)η transitions was performed by the BESIII Collaboration very recently. Inspired by this experimental study, we compute the lowest-order contribution to branching ratios of B(V→¯νν) with V denoting ρ, ω, ϕ, as the standard model background to these invisible decays. Our predictions are far below the upper bounds given by the BESIII experiment. We also analyze the J/ψ→η(η′)¯νν processes and estimate their decay rates. Furthermore, the invisible decays of light pseudoscalar mesons P including π0, η, and η′ are reexamined in the present paper. It is shown that, due to the helicity suppression of the two-neutrino final state, the standard model contributions to P→invisible decays are dominated by P→¯νν¯νν processes. [ABSTRACT FROM AUTHOR]

Rare weak decays of η' → Kπ have been investigated in the framework of the U(3) chiral perturbation theory at the leading order. Our study shows that the branching ratio B(η' → Kπ) is of the order of 10-11, which is far below the present experimental upper bound given by the BESIII Collaboration. By further analysis of η' → K+π- and η' → K0π0, the ratio of isospin amplitudes is found, |A1/2/A3/2| ≃ 35, which supports that the ΔI = 1/2 transition enhancement, namely, the ΔI = 1/2 rule, could be functional in η' weak decays. [ABSTRACT FROM AUTHOR]