Weak leptonic decay of light and heavy pseudoscalar mesons in an independent quark model

Abstract

Weak leptonic decays of light and heavy pseudoscalar mesons are studied in a field-theoretic framework based on the independent quark model with a scalar-vector harmonic potential. Defining the quark-antiquark momentum distribution amplitude obtainable from the bound quark eigenmodes of the model with the assumption of a strong correlation between quark-antiquark momenta inside the decaying meson in its rest frame, we derive the partial decay width with correct kinematical factors from which we extract an expression for the pseudoscalar decay constants fM. Using the model parameters determined from earlier studies in the light-flavor sector and heavy-quark masses m, and mb from the hyperfine splitting of (D*,D) and (B*,B), we calculate the pseudoscalar decay constants. We find that while (f,, fK)=(138,157 MeV); (f,, fDx)=(161,205 MeV), ( fB,fBs)=(122,154 MeV), and fBc=221 MeV. We also obtain the partial decay widths and branching ratios for some kinematically allowed weak leptonic decay processes. 12.40.Qq I. INTRODUCTION B mesons. Capstick and Godfrey [I 11 use the so-called "mock-meson" approach to calculate the hadronic matrix elements f o r obtaining the relativized quark-model The discovery of heavy-flavored mesons in the charm expresson for f M .

Study of the leptonic decays of pseudoscalarB,Dand vectorB*,D*mesons and of the semileptonicAlbertus1, Hernández2, Nieves3 et al. 2005Phys. Rev. D

“…[11] within a non relativistic version, to continue with different versions of the relativistic quark model applied to the determination of decay constants [12,13,14,15,16,17,18,19,20,21], form factors and differential decay widths [19,21,22,23,24,25,26,27], Isgur-Wise functions [21,28,29,30,31,32,33,34] or strong coupling constants [19,32,35,36,37,38] 1 .…”

Exclusive semileptonic decay ofDandBmesons in the independent quark model

“…The quark-gluon interaction at the short distance originating from one-gluon-exchange and quark-pion interaction required in the nonstrange sector to preserve chiral symmetry are presumed tb be residual interactions compared to the dominant confining interaction. Although these residual interactions treated pertwbatively in the model are crucial in generating mass splittings [22,24,25,27], in the hadron spectroscopy, their role in the ha&on& decay processes are considered less significant. Therefore, to a first approximation, it is believed that the zeroth-order quark dynamics inside the meson core, generated by the confining part of the interaction which is phenomenologically represented by U(r) in the Eq.…”

“…We therefore consider it worthwhile to investigate the semileptonic decay of heavy flavored mesons (D and B) in a relativistic independent quark model whose predictive power have been successfully demonstrated in the radiative [19,20], leptonic [Zl], weak leptonic [22], and weak radiative [23] decays as well as in the study of sev-1366 0 1996 The American Physical Society era1 other hadronic phenomena 124-261. We intend here to generate the qz dependence of the relevant form factors directly from the model without taking resort to any kind of pole ansatz.…”

Electric polarizability of pions in semirelativistic quark model

“…In [31] it is shown within the QCD framework that, in order to describe the mass spectrum of light mesons well, it is enough to have only one parameter: string tension. In [32][33][34][35] the potential also does not contain the Coulomb part, since the Coulomb type interac tion is supposed to play a less important role for light mesons. Therefore, to estimate electric pion polariz ability, we shall use in this paper a linear potential of quark-antiquark interaction and a procedure devel oped in [20] on the basis of quantum mechanical per turbation theory.…”