No abstract

We investigate the spectroscopy and decays of the charmonium and upsilon systems in a potential model consisting of a relativistic kinetic energy term, a linear confining term including its scalar and vector relativistic corrections and the complete perturbative one-loop quantum chromodynamic short distance potential. The masses and wave functions of the various states are obtained using a variational technique, which allows us to compare the results for both perturbative and nonperturbative treatments of the potential. As well as comparing the mass spectra, radiative widths and leptonic widths with the available data, we include a discussion of the errors on the parameters contained in the potential, the effect of mixing on the leptonic widths, the Lorentz nature of the confining potential and the possible cc interpretation of recently discovered charmonium-like states.

No abstract

The effect of unitarization on the s-wave amplitudes for the coupled W , W , -zfzf system is studied using the Pade-approximant method and the complete one-loop expressions for the perturbative amplitudes. For values of the Higgs-boson-mass parameter m,, less than 1.0 TeV, the Pade amplitudes and those unitarized using the one-loop K-matrix method are essentially identical. When m,, which also determines the strength of the Higgs-boson self-coupling in the standard model, exceeds 2.6 TeV, the Pade amplitudes begin to develop a resonant feature below the value of m,. The K-matrix amplitudes do not develop a low-mass resonance. At m,= 10 TeV, this peak occurs at about 1.4 TeV, while at m,=50 TeV, it occurs at 950 GeV with a width of about 325 GeV. The Argand diagrams exhibit resonant behavior at these energies. By examining the Argand diagrams for a large range of values of m,, it appears that this Higgs-hoson-like resonance has a mass that does not exceed 2.6 TeV. It is also evident that both the mass and width of the resonance decrease as m , increases beyond 10 TeV. The couplings of the resonance to WL W[ and Z~Z ; are similar to the standard-model couplings of a low-mass elementary Higgs boson. We compare our conclusions with those reached by Dobado, Herrero, and Truong for W, ' W [ scattering.

cFand bbspectra, including fine and hyperfine structures, are investigated with the use of a recently derived quantum-chromodynamic potential supplemented by a phenomenological longrange confining potential. Our theoretical results for all energy levels below the charm and bottom thresholds as well as their leptonic widths are in excellent agreement with experiments. We also give unambiguous theoretical predictions for unobserved bbenergy levels, and present reasonable estimates for energy levels of Our values of the strong coupling constant a, and the QCD scale parameter A are consistent with those extracted from high-energy positronelectron annihilation. (i) Introduction.Recently the quark-antiquark potential to the fourth order in perturbative quantum chromodynamics was obtained' with special emphasis on a precise determination of the spin-dependent interaction terms. We shall now investigate the cF, b& and gspectra, including their fine and hyperfine structures, with the use of this quantum-chromodynamic potential supplemented by a phenomenological long-range confining potentiaL2The confining potential was originally taken to be a spin-independent linear potential.3 But it was subsequently pointed out4" that relativistic corrections to the linear potential will give rise to spin-dependent terms, whose nature depends on whether we regard the confining potential as a vector or a scalar exchange. Our approach is based on the belief that the quark-antiquark potential at short distances can be determined fairly accurately by perturbative quantum chromodynamics, and therefore the confining terms should not unduly affect the potential at short distances, which requires the confining potential to be a scalar exchange.It is well known that results of physical interest obtained from perturbative quantum chromodynamics