Related papers: Electromagnetic probes as signatures for a first-o…
A first order phase transition leading to deconfinement and chiral restoration is a likely possibility for QCD, at least in some region of the temperature-density plane. A signal for a unique transition is that the order parameters for such…
In order to elucidate the enhancement of pion production that may occur during dynamical scenarios of interest in connection with disoriented chiral condensates, we study the evolution of boson modes whose frequencies have a given arbitrary…
This work calculates the first correction to the leading order q\={q} dilepton production rates due to shear viscosity in an expanding gas. The modified rates are integrated over the space-time history of a viscous hydrodynamic simulation…
We study the dynamics of the chiral phase transition expected during the expansion of the quark-gluon plasma produced in a high energy hadron or heavy ion collision, using the $O(4)$ linear sigma model in the mean field approximation.…
It is investigated under which conditions an adiabatic adaption of the dynamic and spectral information of vector mesons to the changing medium in heavy ion collisions, as assumed in schematic model calculations and microscopic transport…
The effects of collisional processes in the hot QCD medium to thermal dilepton production from $q\overline{q}$ annihilation in relativistic heavy-ion collisions have been investigated. The non-equilibrium corrections to the momentum…
A systematic study of intermediate invariant mass dilepton production in Pb+Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV is performed, using next-to-leading-order (NLO) thermal QCD dilepton emission rates with a multistage dynamical approach…
The intrinsic fluctuations, memory effects and long-range color interactions in high energy nuclear collisions imply the presence of non-Markovian processes in the fireball evolution, which affects the thermalization process towards…
We study the chiral phase transition by the non-equilibrium propagation of the sigma field. A quark fluid acts as a heat bath in local thermal equilibrium and evolves fluid dynamically. We allow for dissipative processes and fluctuations…
Discontinuous quantum phase transitions besides their general interest are clearly relevant to the study of heavy fermions and magnetic transition metal compounds. Recent results show that in many systems belonging to these classes of…
We present a newly developed hybrid hadronic transport + hydrodynamics framework geared towards heavy ion collisions at low to intermediate beam energies, and report on the resulting excitation function of dileptons. In this range of…
We review the potential of precise measurements of electromagnetic probes in relativistic heavy-ion collisions for the theoretical understanding of strongly interacting matter. The penetrating nature of photons and dileptons implies that…
Dilepton production in heavy-ion collisions at various energies is studied using coarse-grained transport simulations. Microscopic output from the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model is hereby put on a grid of…
We examine the non-equilibrium time evolution of the hadronic plasma produced in a relativistic heavy ion collision, assuming a spherical expansion into the vacuum. We study the $O(4)$ linear sigma model to leading order in a large-$N$…
We present a fully dynamical model to study nonequilibrium effects in both the chiral and the deconfinement phase transition. The sigma field and the Polyakov loop as the corresponding order parameters are propagated by Langevin equations…
The production of dileptons with an invariant mass in the range 1 GeV < M < 5 GeV provides unique insight into the approach to thermal equilibrium in ultrarelativistic nucleus-nucleus collisions. In this mass range, they are produced…
The pion-to-proton ratio is identified as a potential signal for a non-equilibrium first-order chiral phase transition in heavy-ion collisions, as the pion multiplicity is directly related to entropy production. To showcase this effect, a…
In addition to signals for the critical point, evidence for a first order phase transition would indicate a nontrivial structure within the QCD phase diagram. Moreover, while not a direct measurement of the critical point, the presence of a…
We calculate dilepton production rates from a fireball adapted to the kinematical conditions realized in ultrarelativistic heavy ion collisions over a broad range of beam energies. The freeze-out state of the fireball is fixed by hadronic…
It is argued that, in heavy ion collisions, thermal dileptons are good probes of the transport properties of the medium created in such events, and also of its early-time dynamics, usually inaccessible to hadronic observables. In this work…