120370576
Extended transverse-momentum analysis for intermediate-energy heavy-ion collisions
Abstract An extension of the transverse-momentum analysis of Danielewicz and Odyniec is proposed. This extension involves a consideration of baryonic p T -distribution widths in and out of the reaction plane. Calculations within one- and two-fluid mean-field models show that such an analysis allows us to extract more information on the nuclear equation of state and stopping power than the conventional one does. Different criteria for selecting collision events (i.e. sorting them out according to impact parameters) are also examined. Selections according to the baryonic multiplicity in the midrapidity region and the transversal-to-longitudinal energy ratio are found to be suitable for this purpose.
118142337
Partial-transparency effects in high-energy collisions of heavy ions
A model is proposed for heavy-ion collisions at E/sub lab/approx.1 GeV/nucleon for the case of an incomplete statistical equilibrium in the highly excited nuclear matter. This approach can reproduce the characteristic double-humped structure of the experimental rapidity distributions of secondary particles.
14791019
Lattice QCD constraints on hybrid and quark stars
A QCD-motivated dynamical-quasiparticle model with parameters adjusted to reproduce the lattice-QCD equation of state is extrapolated from the region of high temperatures and moderate baryonic densities to the domain of high baryonic densities and zero temperature. The resulting equation of state matched with realistic hadronic equations of state predicts a phase transition into the quark phase at higher densities than those reachable in neutron star interiors. This excludes the possibility of the existence of hybrid (hadron-quark) stars. Pure quark stars are possible and have low masses, small radii, and very high central densities. Similar results are obtained for a simple bag model with massive quarks, fitted to reproduce the same lattice results. Self-bound quark matter is also excluded within these models. Uncertainties in the present extrapolation are discussed. Comparison with standard bag models is made.
115321070
On the relationship between Boltzmann-Langevin and Boltzmann-Uehling-Uhlenbeck models
195334493
Quantum simulations of strongly coupled quark-gluon plasma
A strongly coupled quark-gluon plasma (QGP) of heavy constituent quasi-particles is studied by a path-integral Monte-Carlo method. This approach is a quantum generalization of the classical molecular dynamics by Gelman, Shuryak, and Zahed. It is shown that this method is able to reproduce the QCD lattice equation of state. The results indicate that the QGP reveals liquid-like rather than gaslike properties. Quantum effects turned out to be of prime importance in these simulations.
18368050
Equation of State of Strongly Coupled Quark–Gluon Plasma – Path Integral Monte Carlo Results
A strongly coupled plasma of quark and gluon quasiparticles at temperatures from 1.1Tc to 3Tc is studied by path integral Monte Carlo simulations. This method extends previous classical nonrelativistic simulations based on a color Coulomb interaction to the quantum regime. We present the equation of state and find good agreement with lattice results. Further, pair distribution functions and color correlation functions are computed indicating strong correlations and liquid-like behavior (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
124036154
ON INFLUENCE OF TWIST CORRECTIONS UPON SIN**2-theta-w
124707884
The Decay $\tau \to 3 \pi \nu_\tau$ and Characteristics of $A1$ Meson
The phenomenological meson Lagrangian based on the four-quark interactions of the scalar, pseudoscalar, vector and axial-vector types is used for description of the decay τ−→π+π−π−vτ. The structure of the main hadronic vertexa 1 − ρπ is discussed. The expression for the axial hadronic currentJμ(a1→3π) is obtained. The low-energy limit of this current is analysed. Spectral functions for the main channel of the given process are calculated. The fitting of the experimental data leads to the following values of thea1 parameters: 
 
$$\begin{gathered} m_{a_1 } = 1242 \pm 37MeV,\Gamma _{a_1 } = 465_{ - 143}^{ + 228} MeV\left( {DELCO} \right); \hfill \\ \hfill \\ m_{a_1 } = 1260 \pm 14MeV,\Gamma _{a_1 } = 298_{ - 34}^{ + 40} MeV\left( {MARK II} \right); \hfill \\ \hfill \\ m_{a_1 } = 1250 \pm 9MeV,\Gamma _{a_1 } = 488 \pm 32MeV\left( {ARGUS} \right). \hfill \\ \end{gathered} $$
6453654
Photoproduction of charmonia and total charmonium proton cross-sections
Elastic virtual photoproduction cross sections ${\ensuremath{\gamma}}^{*}\stackrel{\ensuremath{\rightarrow}}{p}J/\ensuremath{\psi}({\ensuremath{\psi}}^{\ensuremath{'}})p$ and total charmonium-nucleon cross sections for $J/\ensuremath{\psi}, {\ensuremath{\psi}}^{\ensuremath{'}},$ and $\ensuremath{\chi}$ states are calculated in a parameter-free way with the light-cone dipole formalism and the same input: factorization in impact parameters, light-cone wave functions for the ${\ensuremath{\gamma}}^{*}$ and the charmonia, and the universal phenomenological dipole cross section which is fitted to other data. The charmonium wave functions are calculated with four known realistic potentials, and two models for the dipole cross section are tested. Very good agreement with data for the cross section of charmonium photoproduction is found in a wide range of s and ${Q}^{2}.$ The inclusion of the Melosh spin rotation increases the ${\ensuremath{\psi}}^{\ensuremath{'}}$ photoproduction rate by a factor of 2\char21{}3 and removes previously observed discrepancies in the ${\ensuremath{\psi}}^{\ensuremath{'}}$ to $J/\ensuremath{\psi}$ ratio in photoproduction. We also calculate the charmonium-proton cross sections whose absolute values and energy dependences are found to correlate strongly with the sizes of the states.
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.
182081169
PHOTON PROPAGATOR ASYMPTOTICS AT Q**2 ---> infinity IN THE SOURCE THEORY