B→η(η′)K(π)in the standard model with flavor sym

Abstract

The observed branching ratios for B→KЈ decays are much larger than factorization predictions in the standard model ͑SM͒. Many proposals have been made to reconcile the data and theoretical predictions. In this paper we study these decays within the SM using flavor SU͑3͒ symmetry. Treating the singlet 1 and octet ( Ϯ,0 ,K Ϯ ,K 0 ,K 0 , 8 ) pseudoscalar mesons as a nonet multiplet, we find that if small annihilation amplitudes are neglected only 11 hadronic parameters are needed to describe B→ PP decays where P can be one of the , K, and Ј mesons. We find that existing data are consistent with the SM. We also predict several measurable branching ratios and CP asymmetries for B→K()(Ј), (Ј)(Ј) decays. Experiments in the near future can provide important tests for the standard model with flavor symmetry.

Bmeson decays to charmless meson pairs containingηorη′mesons

“…The results shown in Tables II and III are consistent with, but generally more precise than, previous measurements [2,3] and supersede our previous ones [2]. The branching fraction results are in agreement with predictions within the theoretical uncertainties that limit discrimination between different models [4][5][6][7][8][9][10]. We find evidence for three B 0 decay modes: K 0 (3:5'), !…”

“…These branching fraction and charge asymmetry measurements represent an improvement over previous results published by BABAR [2] and Belle [3]. The branching fractions and charge asymmetries of the charmless hadronic B decays are predicted using approaches based on QCD factorization [4][5][6][7] and flavor SU(3) symmetry [8][9][10]. These B decays proceed through loop (penguin) and suppressed tree diagram amplitudes, as shown in Fig.…”

Charmed baryon weak decays with SU(3) flavor symmetry

“…On the other hand, with the advantage of avoiding the detailed dynamics of QCD, the approach with SU(3) flavor (SU(3) f ) symmetry can relate decay modes in the b and c-hadron decays [22,[28][29][30][31][32][33][34][35][36][37], where the SU(3) amplitudes receive non-perturbative and non-factorizable effects, despite the unknown sources. In this paper, in terms of SU(3) f symmetry, we will examine the semileptonic and non-leptonic two-body B c decays, search for decay modes accessible to experiment, and establish the spectroscopy of the charmed baryon states.…”

Observation ofB+→ηρ+and search forB0decays toηAubert1, Bóna2, Karyotakis3 et al. 2008Phys. Rev. D11000View full textAdd to dashboardCite

“…For B 0 → η ′ π 0 and B 0 → ηπ 0 the color-suppressed tree diagram is suppressed by approximate cancellation between the amplitudes for the π 0 and for the isoscalar meson that contains the spectator quark. The approximate ranges of expectations [1,2,3,4,5,6,7] for the branching fraction are ∼10×10 −6 for B + → ηρ + , 0.3-2×10 −6 for B 0 → η ′ η, 0.2-1.0×10 −6 for B 0 → η (′) π 0 , and ∼0.1×10 −6 for B 0 → ωπ 0 . Direct CP violation could be detected as a charge asymmetry, defined as A ch ≡ (Γ − −Γ + )/(Γ − +Γ + ), where the superscript on the width Γ corresponds to the sign of the B ± meson; A ch for B + → ηρ + is expected to be small since the decay is dominated by a single amplitude.…”

“…For the ηρ + mode, we measure the charge asymmetry A ch (B + → ηρ + ) = 0.13 ± 0.11 ± 0.02. Measurements of charmless B decays are now routinely used to test the accuracy of theoretical predictions based on, for example, QCD factorization [1,2], flavor SU(3) symmetry [3,4,5], perturbative QCD [6], or soft collinear effective theory [7]. We present measurements of the branching fraction and charge asymmetry for the decay B + → ηρ + (charge conjugate reactions are implied throughout this paper), superseding our previous result that found a 4.7σ signal for this decay [8] with a luminosity of about one-half that used in this paper.…”