Untitled

Quark-antiquark potential with retardation and radiative contributions and the heavy quarkonium mass spectra

“…In particular, as it has been shown in ref. [8], agreement with experiments for these decays can be achieved only for a mixture of vector and scalar potentials. In this context, it is worth remarking, that the recent study of the qq interaction in the Wilson loop approach [9] indicates that it cannot be considered as simply a scalar.…”

“…The radiative M1-transitions in quarkonia such as e. g. J/ψ → η c γ are the most sensitive to the Lorentz-structure of the confining potential. The relativistic corrections for these decays arising from vector and scalar potentials have different signs [7,8]. In particular, as it has been shown in ref.…”

“…The scalar potential gives a vanishing long-range magnetic contribution, which is in agreement with the flux tube picture of quark confinement of [6], and allows to get the fine structure for heavy quarkonia in accord with experimental data. However, the calculations of electroweak decay rates of heavy mesons with a scalar confining potential alone yield results which are in worse agreement with data than for a vector potential [7,8]. The radiative M1-transitions in quarkonia such as e. g. J/ψ → η c γ are the most sensitive to the Lorentz-structure of the confining potential.…”

“…There is the following set of parameters: the quark masses (m b and m c ), the QCD constant Λ and renormalization point µ (see Eqs. (46), (44), (48)) in the short-range part of the QQ potential, the slope A and intercept B of the linear confining potential (10), the mixing coefficient ε (9), the longrange anomalous chromomagnetic moment κ of the quark (8), and the mixing parameter λ S in the retardation correction for the scalar confining potential (26). As it was already discussed in Sec.…”

“…The quark masses m b = 4.88 GeV, m c = 1.55 GeV and the parameters of the linear potential A = 0.18 GeV 2 and B = −0.16 GeV have usual values of quark models. The value of the mixing coefficient of vector and scalar confining potentials ε = −1 has been determined from the consideration of the heavy quark expansion for the semileptonic B → D decays [22] and charmonium radiative decays [8]. Finally, the universal Pauli interaction constant κ = −1 has been fixed from the analysis of the fine splitting of heavy quarkonia 3 P J -states [20].…”