Narrow Results

The chiral structure of heavy-light mesons is explored with a particular focus on the nature of the D_sJ charmed mesons. Theoretical predictions for the hadronic and radiative decays of these mesons are compared to recent experimental data.

We present the first results from a recent pilot run of the CLEO-c experiment. This new program investigates the physics of charm mesons and charmonium resonances. We begin with results on two-body decays of the ψ(2S); first observations of some highly-suppressed "PV" modes are presented. Next, data taken at the ψ(3770) are used for a variety of studies of D meson decays in a very clean environment. We report the cross-section at the ψ(3770), extract f_D from the first significant sample of D⁺→μ⁺ν_μ decays, and investigate both inclusive and exclusive semileptonic D decays.

In my talk I discussed the properties of the newly discovered , D_sJ(2460), X(3872), and SELEX states and suggested experimental measurements that can shed light on them. In this writeup I concentrate on an important facet of under-standing the D_sJ states, the properties of the closely related and D′₁ states. These states are well described as the broad, j = 1/2 non-strange charmed P-wave mesons.

The radiative leptonic decays D_s → μν_μγ and D → μν_μγ are investigated at the tree level within the relativistic independent quark model based on the confining potential in the scalar–vector harmonic form. The branching ratios for these decays in the vanishing lepton mass limit are obtained as ℬr(D_s → μν_μγ) = 4.94×10^-4 and ℬr(D → μν_μγ) = 3.34×10^-5, which includes the contributions of the internal bremsstrahlung and structure dependent diagrams at the level of the quark constituents. Finally, the photon energy spectra as predicted here is found to be symmetric about the peak value of the photon energy at .

In this work we formulate the Galilei-covariant version of an effective theory containing nonrelativistic heavy mesons and pions as degrees of freedom. This manifestly Galilean covariant framework is based on a five-dimensional space–time that has been used in the description of covariant nonrelativistic physics. In this context, effective Lagrangian is introduced without ambiguities, containing kinetic and interaction terms that are naturally Galilean invariant. The leading-order scattering amplitudes and the properties of possible heavy-meson bound states are calculated and discussed.

We first review recent measurements of D → μν and D_s → μν, τν from CLEO-c. These decays are used to determine leptonic decay constants f_D and f_Ds which may be compared to modern Lattice QCD (LQCD) calculations. Such cross-checks can provide confidence in Lattice results for B_(s) meson decay constants which are needed to fully exploit data used to extract the CKM matrix elements V_ub and V_cb. We also comment briefly on the outlook for further progress at BESIII.

We review the recent measurements of rare and forbidden decays of charmed mesons at the B-factories. A preliminary result of the first measurement of orbitally excited meson radiative decay to D⁰γ final state, and the most sensitive determination of limits on the leptonic D⁰ → ℓ⁺ ℓ^- decays are briefly described.