124036154
ON INFLUENCE OF TWIST CORRECTIONS UPON SIN**2-theta-w
182432079
SPECTRALITY OF GELL-MANN-LOW FUNCTION
896237
Electroproduction of charmonia off nuclei
In a recent publication we have calculated elastic charmonium production in ep collisions employing realistic charmonia wave functions and dipole cross sections and have found good agreement with the data in a wide range of s and Q^2. Using the ingredients from those calculations we calculate exclusive electroproduction of charmonia off nuclei. Here new effects become important, (i) color filtering of the c-cbar pair on its trajectory through nuclear matter, (ii) dependence on the finite lifetime of the c-cbar fluctuation (coherence length) and (iii) gluon shadowing in a nucleus compared to the one in a nucleon. Total coherent and incoherent cross sections for C, Cu and Pb as functions of s and Q^2 are presented together with some differential cross sections. The results can be tested with future electron-nucleus colliders or in peripheral collisions of ultrarelativistic heavy ions.
118014393
QCD analysis of deep inelastic lepton-scattering data
We have carried out a QCD analysis of data on deep inelastic lepton-scattering (using data of the collaborations BCDMS, EMC, and CDHS) in the leading and next-to-leading orders in the coupling constant ..cap alpha../sub s/. We have considered the effect of the sea quarks and gluons. We discuss the dependence of our results for ..lambda.. on effects of twist corrections, nuclear target effects, and heavy-quark production thresholds.
119138207
Lepton flavor violating photoleptonic effect
We study lepton flavor violating analogs of the photoelectric effect, with a final μ or T instead of an electron: γe → μ and γe → T. On the basis of the general parametrization of the matrix element of the electromagnetic current we estimate the upper limits for the cross sections and event rates of these processes, imposed by the current experimental bounds on μ → ey and T → eγ decays.
117509698
QCD NUCLEON MODEL WITH RELATIVISTIC OSCILLATOR INTERACTION BETWEEN CONSTITUENT QUARK
117827292
Surface oscillations of a Fermi liquid
Abstract Surface oscillations of a normal Fermi liquid are considered within the framework of the Landau phenomenological theory of a Fermi liquid. A procedure for describing surface phenomena is formulated which is based on the self-consistent field kinetic equation involving successive separation of the surface parts of various characteristics of the liquid. Boundary conditions at the free surface are derived. An expression for the surface tension coefficient is obtained. Oscillations of a Fermi liquid under hydrodynamical and collisionless conditions are investigated and the density and current distributions in the presence of such oscillations are found. The role of system finiteness effects is discussed. It is concluded that weakly damped low-lying surface vibrations in nuclei exist only as a result of nuclear finiteness. The contribution of surface fluctuations to the free energy of a Fermi liquid is calculated. The analytic dependence of the surface tension coefficient upon the temperature is predicted in the low-temperature limit.
16049954
Soft modes, resonances, and quantum transport
Effects of the propagation of particles that have a finite lifetime and an according width in their mass spectrum are discussed in the context of transport description. First, the importance of coherence effects (Landau-Pomeranchuk-Migdal effect) on the production and absorption of field quanta in nonequilibrium dense matter is considered. It is shown that classical diffusion and Langevin results correspond to a resummation of certain field-theory diagrams formulated in terms of full nonequilibrium Green's functions. General properties of broad resonances in dense and hot systems are discussed in the framework of a self-consistent and conserving Φ-derivable method of Baym by considering the examples of the ρ meson in hadronic matter and the pion in dilute nuclear matter. Further, we address the problem of a transport description that properly takes into account the damping width of the particles. The Φ-derivable method generalized to the real-time contour provides a selfconsistent and conserving kinetic scheme. We derive a generalized expression for the nonequilibrium kinetic entropy flow, which includes corrections from fluctuations and mass-width effects. In special cases, an H theorem is proven. Memory effects in collision terms contribute to the kinetic entropy flow that, in the Fermi liquid case, reproduces the famous bosonic-type T3lnT correction to the specific heat of liquid 3He. For the example of the pion-condensate phase transition in dense nuclear matter, we demonstrate the important role of the width effects within the quantum transport.
116272686
Dynamical Instabilities in Relativistic Heavy-Ion Collisions and Associated Phenomena
123021094
Analysis of intermediate-energy heavy-ion collisions within relativistic mean-field two-fluid model
A three-dimensional realization of the relativistic mean-field two-fluid model is described. First results of analyzing the inclusive data on the yield of nuclear fragments and pions, as well as the Plastic-Ball rapidity distributions of nuclear fragments are presented. For comparison, calculations within the conventional relativistic hydrodynamical model with the same mean fields are also performed. In spite of a pronounced sensitivity of the nuclear dynamics to the nuclear equation of state (more precisely, to the form of the mean fields), it is found that all the analyzed observables, except the pion spectra, appear to be fairly insensitive to it. The sensitivity to the nuclear stopping power is slightly higher. The original sensitivity of the rapidity distributions to the stopping power is smeared out by the Plastic-Ball filter and selection criterion. Nevertheless, one can conclude that the stopping power induced by the Cugnon parametrization of the nucleon-nucleon cross sections is not quite sufficient for a more adequate reproduction of the experimental data.
125142837
The effect of a hot jet in the hydrodynamic theory of heavy ion collisions