Related papers: Nonequilibrium meson production in strong fields
We explore the photoproduction mechanisms for charged and neutral pion pairs off a heavy nucleus at threshold. We calculate the production of charged pairs in the Coulomb field of the nucleus in the Born approximation using explicit…
We analyse the extension of Chiral Perturbation Theory to describe a meson gas out of thermal equilibrium. For that purpose, we let the pion decay constant be a time-dependent function and work within the Schwinger-Keldysh contour…
The present status of our understanding of low mass dilepton production in relativistic heavy ion collisions is discussed. The focus of the discussion will be the sensitivity of dilepton measurements to in medium changes of hadrons and the…
Pion production in heavy-ion collisions at intermediate energies provides an important probe of the collision dynamics and nuclear matter equation of state, especially the high-density behavior of the symmetry energy. Using the lattice…
The meson production cross sections are estimated considering photon-photon interactions in hadron - hadron collisions at CERN LHC energies. We consider a large number of mesons with photon-photon partial decay width well constrained by the…
We study the dilepton production in heavy-ion collisions at energies of 1-2 AGeV as well as in proton induced pp, pn, pd and p+A reactions from 1 GeV up to 3.5 GeV. For the analysis we employ three different transport models - the…
Recent progress in the field of meson production in hadron collisions is presented. Special emphasis is put new developments in the application of effective field theory methods to pion production, but also theoretical concepts for…
The microscopic description of heavy-ion reactions at low beam energies is achieved within hadronic transport approaches. In this article a new approach SMASH (Simulating Many Accelerated Strongly-interacting Hadrons) is introduced and…
We investigate the production of pions in heavy-ion collisions in the energy range of $1$ - $2$ GeV/A. The dynamics of the nucleus-nucleus collisions is described by a set of coupled transport equations of the Boltzmann-Uehling-Uhlenbeck…
Using a relativistic transport model to describe the expansion of the fire-cylinder formed in the initial stage of heavy-ion collisions at SPS/CERN energies, we study the production of dileptons with mass below about 1 GeV from these…
In a homogeneous pionic gas system, chemical nonequilibrium process is considered to understand its effect in the expansion processes that are realized immediately after heavy ion collisions. The chemical relaxation time is calculated by…
In the framework of the linear sigma model, we study the time evolution of a system of classical $\sigma$ and pion fields coupled to quarks. For this purpose we solve numerically the classical transport equation for relativistic quarks…
We propose to study the non-equilibrium features of heavy-ion collisions by following the evolution of an initial state with a large number of quanta with a distribution around a momentum |\vec k_0| corresponding to a thin spherical shell…
The nonequilibrium dynamics of the chiral phase transition expected during the expansion of the quark-qluon plasma produced in a high energy hadron or heavy ion collision is studied in the O(4) linear sigma model to leading order in a large…
We address the problem of pion production in low energy $\pi$-nucleus collisions. For the production mechanism we assume a simple model consisting of a coherent sum of single pion exchange and the excitation---followed by the decay into two…
A new mechanism for the pion production in the high energy reactions is suggested. It is related to the possibility for direct production of the pions induced by instantons, topologically nontrivial gluonic excitations of QCD vacuum. This…
We develop a quantum kinetic theory of the chiral condensate and meson quasi-particle excitations using the O(N) linear sigma model which describe the chiral phase transition both in and out of equilibrium in a unified way. A mean field…
Multiple soft pion production in the baryon scattering reactions is considered in the framework of chiral nonlinear sigma model neglecting the pion mass. Treating baryons in the eikonal approximation as classical sources, a set of…
The photon pair production by pion annihilation in a hot and dense medium at the chiral phase transition is investigated within a chiral quark model. As a direct consequence of this transition the $\sigma$ meson appears as a bound state in…
Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the dynamics of pion emission in heavy-ion collisions in the region 1 A GeV as a probe of nuclear symmetry energy at supra-saturation…