Narrow Results

In the framework of potential models for heavy quarkonium, we compute the mass spectrum of the bottom-charmed B_c meson system and spin-dependent splittings from the Schrödinger equation using the shifted-large-N expansion technique. The masses of the lightest vector and pseudoscalar B_c states as well as the higher states below the threshold are estimated. Our predicted result for the ground state energy is MeV and are generally in exact agreement with earlier calculations. Calculations of the Schrödinger energy eigenvalues are carried out up to the third order of the energy series. The parameters of each potential are adjusted to obtain best agreement with the experimental spin-averaged data (SAD). Our findings are compared with the observed data and with the numerical results obtained by other numerical methods.

We calculate the mass spectrum, the splitting values and some other properties in the framework of the semirelativistic equation by applying the shifted large-N expansion technique. We use seven different central potentials together with an improved QCD-motivated interquark potentials calculated to two loops in the modified minimal-subtraction scheme. The parameters of these potentials are fitted to generate the semirelativistic bound states of quarkonium system in close conformity with the experimental and the present available calculated center-of-gravity (c.o.g.) data. Calculations of the energy bound states are carried out up to third order. Our results are in excellent fit with the results of the other works.

We reproduce masses of the self-conjugate and non-self-conjugate mesons in the context of the spinless Salpeter equation taking into account the relativistic kinematics and the quark spins. The hyperfine splittings for the 2S charmonium and 1S bottomonium are also calculated. Further, the pseudoscalar and vector decay constants of the B_c meson and the unperturbed radial wave function at the origin are also calculated. We have obtained a local equation with a complete relativistic corrections to a class of three attractive static interaction potentials of the general form V(r) = -Ar^-β + κr^β + V₀, with β = 1, 1/2, 3/4 decomposed into scalar and vector parts in the form V_V(r) = -Ar^-β + (1-∊)κr^β and V_S(r) = ∊κr^β + V₀; where 0≤∊≤1. We have used the shifted large-N-expansion technique (SLNET) to solve the reduced equation for the scalar (∊ = 1), equal mixture of scalar-vector (∊ = 1/2), and vector (∊ = 0) confinement interaction kernels. The energy eigenvalues are carried out up to the third order approximation.

We present bound state masses of the self-conjugate and non-self-conjugate mesons in the context of the Schrödinger equation taking into account the relativistic kinematics and the quark spins. We apply the usual interaction by adding the spin dependent correction. The hyperfine splittings for the 2S charmonium and 1S bottomonium are calculated. The pseudoscalar and vector decay constants of the B_c meson and the unperturbed radial wave function at the origin are also calculated. We have obtained a local equation with a complete relativistic corrections to a class of three attractive static interaction potentials of the general form V(r) = -Ar^-β+κr^β+V₀, with β = 1, 1/2, 3/4 which can also be decomposed into scalar and vector parts in the form V_V(r) = -Ar^-β+(1-∊)κr^β and V_S(r) = ∊κr^β+V₀; where 0≤∊≤1. The energy eigenvalues are carried out up to the third order approximation using the shifted large-N-expansion technique.

Studies on the decay and production of meson are briefly reviewed. Considering RUN-II of Tevatron and the schedule of LHC, the theoretical studies of B_c meson will jump to a new stage not only for itself but also to implement the studies of the heavy quarkonia etc.

We give a review and present a comprehensive calculation for the leptonic constant f_Bc of the low-lying pseudoscalar and vector states of B_c-meson in the framework of static and QCD-motivated nonrelativistic potential models taking into account the one-loop and two-loop QCD corrections in the short distance coefficient that governs the leptonic constant of B_c quarkonium system. Further, we use the scaling relation to predict the leptonic constant of the nS-states of the system. Our results are compared with other models to gauge the reliability of the predictions and point out differences.

We review recent measurements of heavy B hadron states including masses and lifetimes of the meson as well as excited B states . We discuss properties of the meson such as lifetime, lifetime difference ΔΓ_s/Γ_s and CP violation in decays. We also summarize new measurements of the masses and lifetimes of bottom baryons including the baryon, the Σ_b baryon states as well as the and baryons.