Efforts to predict the rare exclusive decay B → Kγ from the well known inclusive decay b → sγ are frustrated by the effect of the large recoil momentum. We show how to reduce the large uncertainty in calculating this decay by relating B → Kγ to the semileptonic process B → ρeν̄ using the heavy-quark symmetry in B decays and SU(3) flavor symmetry. A direct measurement of the q-spectrum for the se...

We reconsider the prediction of the semileptonic branching ratio of B mesons, using the recent calculation [1] of the radiative corrections with account for finite quark masses in nonleptonic decays and taking into account 1/mb corrections. For the semileptonic branching ratio we obtain BSL = (11.8±1.6)% using pole quark masses and BSL = (11.0± 1.9)% using running MS quark masses. The uncertain...

Quark-gluon decays of heavy paraquarkonia S0(Q̄Q) → q̄qg are investigated with account of the masses of final quarks. The decay widths and the energy distributions of the final quarks and gluons are calculated in dependence on the relative quark masses. The strong collinear enhancement of the gluon energy distribution at the end of the spectrum is shown to take place in all such decays of ηc and ...

We compute the differential momentum correlation function for hadrons produced in the decay of B-mesons. This measure of hadronic event shapes tests the free b-quark decay picture for nonleptonic and semileptonic decays of B-mesons. Our results can also be applied to Bs and Λb decay. UTPT 93-28 CMU-HEP 93-24 CALT-68-1905 DOE-ER/40682-49 November 1993

In this paper we evaluate strong decay amplitudes and partial widths of strange mesons (strangeonia and kaonia) in the P0 decay model. We give numerical results for all energetically allowed open-flavor two-body decay modes of all ns̄ and ss̄ strange mesons in the 1S, 2S, 3S, 1P, 2P, 1D and 1F multiplets, comprising strong decays of a total of 43 resonances into 525 two-body modes, with 891 numer...

It is shown that in realistic SUSY GUT models of quark and lepton masses both the proton decay rate and branching ratios differ in general from those predicted in the minimal SU(5) supersymmetric model. The observation of proton decay, and in particular the branching ratio B[(p → π+ν)/(p → K+ν)], would thus allow decisive tests of these fermion mass schemes. It is shown that the charged lepton ...

The recent BaBar measurement has confirmed substantial strong phases for the B → J/ψK∗ decay amplitudes implying violation of factorization in this decay mode. In the absence of polarization measurement of a lepton pair from J/ψ, however, the relative phases of the spin amplitudes still have a twofold ambiguity. In one set of the allowed phases the s-quark helicity conserves approximately despi...

The polarization properties of the charmed Λc baryon are investigated in weak non–leptonic four–body Λc → p+K−+π++π0 decay. The probability of this decay and the angular distribution of the probability are calculated in the effective quark model with chiral U(3)×U(3) symmetry incorporating Heavy Quark Effective theory (HQET) and the extended Nambu–Jona–Lasinio model with a linear realization of...

The pionic decay of a possible d -dibaryon in the process d → N + N + π is studied in the microscopic quark shell model and with a single-quark transition operator describing the transition q → q + π. For the d with quantum numbers J = 0, T = 0, we employ a six-quark shell-model wave function with a spatial sp[51]X-configuration and with N = 1 harmonic oscillator quanta. It is shown that the pi...

Flavour changing neutral decays of the top quark are know to be extremely suppressed in the SM. This is especially so for the top quark decay into the SM Higgs boson, whose rate is less than 10. However, it turns out that the decay modes t → c h, with h ≡ h, H, A any of the MSSM neutral Higgs bosons, can be much more gifted. In particular, the rate into the lightest CP-even Higgs boson h – whic...