1943581
Quark confinement in quantum chromodynamics.
A quark-confinement mechanism inspired by renormalization-group-improved perturbative quantum chromodynamics is proposed. We obtain a quark-antiquark confining potential in the lowest approximation, show that it yields reasonable results for the bb-bar and cc-bar spin-averaged energy levels, and comment on the significance of the higher-order effects.
122156675
Relativistic Hadron Model with Intrinsic Mass Splittings
A simple mechanism for the $\mathrm{SU}(3)$-symmetry breaking in strong interactions is introduced by using the formalism of the multispinor field equations, which avoids the use of physical quarks but has resemblance to the quark model. The resulting treatment leads to the Gell-Mann-Okubo mass formula for baryons, but not for mesons. It yields approximate values of -19.5\ifmmode^\circ\else\textdegree\fi{} and 33\ifmmode^\circ\else\textdegree\fi{} for the $\ensuremath{\eta}\ensuremath{-}{\ensuremath{\eta}}^{\ensuremath{'}}$ and $\ensuremath{\varphi}\ensuremath{-}\ensuremath{\omega}$ mixing angles, respectively, and also provides a reasonable explanation for the intermultiplet meson mass formula $m_{K}^{}{}_{}{}^{2}\ensuremath{-}m_{\ensuremath{\pi}}^{}{}_{}{}^{2}=m_{{K}^{*}}^{}{}_{}{}^{2}\ensuremath{-}m_{\ensuremath{\rho}}^{}{}_{}{}^{2}$.
120228440
Regularization of fermion loops in gauge models
Fermion loops in gauge models with ${\ensuremath{\gamma}}_{5}$ couplings cannot be regularized in a gauge-invariant manner either by the method of auxiliary fields or by dimensional continuation. It is shown that in the absence of a gauge-invariant regularization procedure, the method of auxiliary fields can be employed in such a way that non-gauge-invariance is confined to the renormalization constants. It is thus possible to obtain gauge-invariant renormalized results as well as resolve anomalies without the use of Ward's identities. Explicit calculations are carried out for the self-energy and triangle diagrams with fermion loops in the Appelquist-Quinn model. The present treatment is also compared with naive dimensional regularization for the ${\ensuremath{\gamma}}_{5}$ couplings.
121297767
High-energy graviton bremsstrahlung
120383870
Higgs model with ghost-field formalism
The Higgs model for the interaction of vector and scalar fields is treated by means of the ghost-field formalism, which preserves the unitarity of the scattering operator as well as simplifies the renormalization procedure. Our ghost-field formalism has some similarity to the ${R}_{\ensuremath{\xi}}$ formalism with $\ensuremath{\xi}=1$, but it does not require the introduction of the so-called gauge-compensating terms. Applications to the second-order self-energy of a scalar particle and to the fourth-order scattering of vector particles are discussed.
122039483
Supplementary Conditions in the Quantized Gravitational Theory
40514876
Hadronic correlation functions in the QCD plasma phase.
We present results for static hadronic correlation functions in the high-temperature phase of QCD with four flavors of dynamical quarks. We confirm chiral-symmetry restoration through the degeneracies of the spectrum of screening lengths. We also find that the screening lengths for the {rho} and {ital N} channels at {ital T}{approx gt}1.2{ital T}{sub {ital c}} are close to that in a free quark gas.
33623649
Simple relationships in the eikonal model of the energy flow in ultrarelativistic heavy ion collisions.
The eikonal model has been formulated in terms of the participant and spectator probabilities. It has been used to relate the number of collisions, the numbers of participants from both the projectile and the target, and the energy in the zero degree detector. It is found by comparison with the recent data that the transverse energy or the charged particle multiplicity is directly proportional to the total number of participant nucleons rather than to the number of collisions.
27086458
Coulomb-modified Glauber model description of heavy-ion elastic scattering at low energies.
The Glauber model approach for the description of elastic scattering has been extended to the low energy range. The overlap integral of the nuclear densities derived in our previous paper has been calculated along a trajectory characterized by the distance of closest approach, to account for the deviation in the projectile trajectory due to the Coulomb field. The only ingredients in this formalism are the densities of the colliding ions and elementary nucleon-nucleon scattering amplitude. At low energies we have given a prescription for the calculation of {alpha}{sub {ital N}{ital N}}, the ratio of real to imaginary part of the forward nucleon-nucleon scattering amplitude. Elastic scattering angular distributions at low energies for several heavy-ion systems are described reasonably well.
21268625
Search for signals from Cygnus X-3 at energies above 50 TeV.
Upper limits for the time-averaged flux of air showers from the direction of Cygnus X-3 during the calendar period 2 April 1986 to 3 May 1987 are found to be 1.5 x 10/sup -13/ cm/sup -2/ sec/sup -1/ for all events, and 7.6 x 10/sup -14/ cm/sup -2/ sec/sup -1/ for events with no observed muons in a 44-m/sup 2/ muon detector. These are integral fluxes above 50 TeV on the assumption of an E/sup -1/ primary spectrum. A possible observation of a short-term signal from Cygnus X-3, with an anomalous muon content, phase correlated with the 4.8-h orbital period, with an integral flux above 50 TeV of (8.2 +- 2.0) x 10/sup -13/ cm/sup -2/ sec/sup -1/ is also reported.
20187829
Calculation of the pion's quark distribution amplitude in lattice QCD with dynamical fermions.
We present a calculation of the pion decay constant and of the second moment of the quark distribution amplitude of the pion within full lattice QCD. Measurements are made on 12{sup 3}{times}24 and 16{sup 3}{times}32 lattices, using two flavors of Wilson fermion. Different methods used to extract {ital f}{sub {pi}} give consistent results. We find a better signal for the second moment of the distribution amplitude than in previous lattice calculations and obtain results that are significantly smaller than those obtained from sum-rule calculations and previously in (quenched) lattice QCD.