Search

The dielectron widths of ψ(4040), ψ(4160), and ψ(4415), and their ratios are shown to be in good agreement with experiment, if in all cases the S-D mixing with a large mixing angle θ ≅ 34° is taken. Arguments are presented why continuum states give small contributions to the wave functions at the origin. We find that the Y (4360) resonance, considered as a pure 3 3 D1 state, would have very small dielectron width, Γ ee( Y (4360)) = 0.060 keV. On the contrary, for large mixing between the 4 3 S1 and 3 3 D1 states with the mixing angle θ = 34.8°, Γ ee( ψ(4415)) = 0.57 keV coincides with the experimental number, while a second physical resonance, probably Y (4360), has also a rather large Γ ee( Y (∼4400)) = 0.61 keV. For the higher Y (4660) resonance, considered as a pure 5 3 S1 state, we predict the dielectron width Γ ee( Y (4660)) = 0.70 keV, but it becomes significantly smaller, namely 0.31 keV, if the mixing angle between the 5 3 S1 and 4 3 D1 states has the characteristic value θ = 34°. The mass and dielectron width of the 6 3 S1 charmonium state are calculated. [ABSTRACT FROM AUTHOR]

The hyperfine splittings in heavy quarkonia are studied in a model-independent way using experimental data on dielectron widths. Relativistic correlations are taken into account together with the smearing of spin-spin interaction. The radius of smearing is fixed by known G/ ψ−η c(1 S), ψ(2 S)− η c′(2 S) splittings, which appears to be small, r ss ≅ 0.06 fm. Nevertheless, even with such a small radius, substantial suppression of hyperfine splittings (∼50%) is observed in bottomonium. For nS b $$\bar b$$ states ( n = 1, 2, ..., 6), our predicted splittings (in MeV) are 28, 12, 10, 5, 6, 3. For the 3 S and 4 S charmonium states, the splittings 16(2) and 12(4) MeV are obtained. [ABSTRACT FROM AUTHOR]

The precision measurement of the hyperfine splitting, ΔHF(1 P, c-c) = M cog( xcJ) — M( h c), in the Fermilab-E835 and CLEO experiments allows one to determine the gluonic condensate G 2 with high accuracy if the gluonic correlation length T g is fixed. In our calculations, the negative value of ΔHF = −0.5 ± 0.4 MeV, as in the E835 experiment, is obtained only if the relatively small T g = 0.16 im and G 2 = 0.060(3) GeV4 are taken. For T g ≥ 0.2 fm, the hyperfine splitting is positive and grows for increasing T g. In particular, for T g = 0.2 fm and G 2 = 0.045(2) GeV4, the splitting ΔHF = 1.0(5) MeV is just in accordance with the recent CLEO result. The values of G 2 taken correspond to the “physical” string tension σ ≈ 0.18 GeV2. [ABSTRACT FROM AUTHOR]

For a[sub 0](1450), considered as the q&qmacr; 1³P[sub 0] state, "experimental" tensor splitting, c[sub exp] = -150 ± 40 MeV, appears to be in contradiction with the conventional theory of fine structure. There is no such discrepancy if a[sub 0](980) belongs to the q&qmacr; 1³P[sub J] multiplet. The hadronic shift of a[sub 0](980) is shown to be greatly dependent on the value of strong coupling in spin-dependent interaction. [ABSTRACT FROM AUTHOR]

It is shown that a 25(20)% difference between the decay constants $$f_{D_s } $$ ( $$f_{B_s } $$ ) and f D ( f B ) occurs due to large differences in the pole masses of the s and d( u) quarks. The values η D = $$f_{D_s } $$ / f D ∼ 1.23(15), recently observed in the CLEO experiment, and η B = $$f_{B_s } $$ / f B ∼ 1.20, obtained in unquenched lattice QCD, can be reached only if, in the relativistic Hamiltonian the running mass, m s at low scale is m s (∼0.5 GeV) = 170–200 MeV. Our results follow from the analytical expression for the pseudoscalar decay constant f P based on the path-integral representation of the meson Green’s function. [ABSTRACT FROM AUTHOR]

The spectrum of the s s ¯ mesons is studied performing a phenomenological analysis of the Regge trajectories defined for the excitation energies. For the ϕ (3 3 S 1) state the mass M (ϕ (3 S)) = 2100 (20) MeV and the leptonic width Γ ee (ϕ (3 S)) = 0.27 (2) keV are obtained, while the mass of the 2 3 D 1 state, M (ϕ (2 3 D 1)) = 2180 (5) MeV, appears to be in agreement with the mass of the ϕ (2170) resonance, and its leptonic width, Γ ee (2 3 D 1) = 0.20 ± 0.10 keV, has a large theoretical uncertainty, depending on the parameters of the flattened confining potential. [ABSTRACT FROM AUTHOR]

Statistical regularities characterizing the temporal distribution of the transitions of continuous paranoid schizophrenia from from stage to stage were studied on a random epidemiological material. It has been shown that the mechanism responsible for those transitions has, in principle, a probability nature, and the distribution as such can be described by a sole parameter which is a value expressing the probability of the disease transition to the next stage within a time unit. It has been also shown that this parameter can serve as a measure of the disease progress.