We present realistic estimates for the duration of hadronic stage in central Au+Au reactions RHIC-BES energy regime. To this aim, we employ a full set coupled rate equations to describe time evolution system from chemical kinetic freeze-out. Combined with recently measured data by STAR collaboration on $K^*/K$ ratios, show that previous substantially underestimated due omission regeneration hadron resonances. provide an improved relation between ratio at and freeze-out life phase. The...

We investigate the development of directed, $v_1$, and elliptic flow, $v_2$, in heavy ion collisions mid-central Au+Au reactions at $E_\mathrm{lab}=1.23 A$ GeV. demonstrate that flow hot dense matter is initially positive ($v_2>0$) due to early pressure gradient. This $v_2$ transfers its momentum spectators, which leads creation directed $v_1$. In turn, spectator shadowing in-plane expansion a preferred decoupling hadrons out-of-plane direction results negative for observable final state...

The ultrarelativistic quantum molecular dynamics model is employed to simulate ${\ensuremath{\pi}}^{\ensuremath{-}}+\mathrm{C}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}+\mathrm{W}$ collisions at ${p}_{\mathrm{lab}}=1.7$ GeV motivated by the recent HADES results. By comparing proton $\mathrm{\ensuremath{\Lambda}}$ transverse momentum spectra, it was observed that data transport calculation show a good agreement, if cluster formation included obtain free spectra. Predictions of light ($d, t,...

We study the production of entropy in context a nonequilibrium chiral phase transition. The dynamical symmetry breaking is modeled by Langevin equation for order parameter coupled to Bjorken dynamics quark plasma. investigate impact dissipation and noise on explore possibility reheating crossover first-order transitions, depending expansion rate fluid. relative increase S/N estimated range from 10% 200% transition at low beam energies, which could be detected pion-to-proton ratio as function energy.

We investigate the coalescence factors ${B}_{2}$ and ${B}_{3}$ at low collision energies ($\sqrt{{s}_{\mathrm{NN}}}<6$ GeV) with special focus on HADES RHIC-Beam Energy Scan (BES) experiments. It is shown that, in order to properly interpret ${B}_{A}$, two important corrections are necessary: (I) has be calculated using proton $\ifmmode\times\else\texttimes\fi{}$ neutron yields denominator, instead of square yield, (II) primordial (neutron) densities have used for normalization not...

Abstract We present UrQMD predictions for the comparison of recently measured Ag+Ag and Au+Au runs at a beam energy E lab = 1.23A GeV explored by HADES experiment. To this aim, different centrality definitions are investigated: suggest that in case particle production, both systems should be compared same number participating nucleons, while (elliptic) flow, selection on initial state eccentricity—as high reactions—is better suited. Generally, we find good agreement between systems, if these...

We investigate the development of directed, $v_1$, and elliptic flow, $v_2$, in heavy ion collisions mid-central Au+Au reactions at $E_\mathrm{lab}=1.23 A$ GeV. demonstrate that flow hot dense matter is initially positive ($v_2&gt;0$) due to early pressure gradient. This $v_2$ transfers its momentum spectators, which leads creation directed $v_1$. In turn, spectator shadowing in-plane expansion a preferred decoupling hadrons out-of-plane direction results negative for observable final state...

Isospin triggering allows to distinguish coalescence from thermal production of light clusters in heavy ion collisions. Triggering on $Y({\ensuremath{\pi}}^{\ensuremath{-}})\ensuremath{-}Y({\ensuremath{\pi}}^{+})$ select very neutron or proton rich final states. The deuteron (cluster) with ($d\ensuremath{\propto}n\ifmmode\cdot\else\textperiodcentered\fi{}p$) leads then an inverse parabolic dependence the yield $\mathrm{\ensuremath{\Delta}}{Y}_{\ensuremath{\pi}}$. In contrast, a model,...

The Ultra-relativistic Quantum Molecular Dynamics model is employed to simulate $\pi^-+\mathrm{C}$ and $\pi^-+\mathrm{W}$ collisions at p$_\mathrm{lab}=1.7$ GeV motivated by the recent HADES results. By comparing proton $\Lambda$ transverse momentum spectra, it was observed that data transport calculation show a good agreement, if cluster formation included obtain free spectra. Predictions of light ($d$, $t$, $^3$He, $^4$He, as well ${}^{3}_\Lambda$H $\Xi$N) multiplicities spectra are made...

We study (anti)deuteron formation rates in heavy-ion collisions the framework of a wave-function based coalescence model. The main feature our model is that nucleons are emitted from whole spherically symmetric fireball volume, while antinucleons only spherical shell close to surface. In this way, accounts for nucleon-antinucleon annihilations center reaction at lower beam energies. Comparison with experimental data on parameter range $\sqrt{s_{NN}}= 4.7-200$ GeV allows us extract radii...

Several ongoing theoretical and experimental projects are exploring the possibility of a QCD critical point phase transition. Here, we propose to study production entropy as signature for first-order chiral Based on linear sigma model, couple order parameter quark fluid describe nonequilibrium cooling fireball in heavy-ion collision. We estimate relative increase per baryon number S/N reach its largest value up 130% transition at low beam energies. The lifetime quark-gluon plasma (QGP)...

We present UrQMD predictions for the comparison of recently measured Ag+Ag and Au+Au runs at a beam energy $E_\mathrm{lab}$ = 1.23~$A$GeV explored by HADES experiment. To this aim, different centrality definitions are investigated: suggest that in case particle production, both systems should be compared same number participating nucleons, while (elliptic) flow, selection on initial state eccentricity - as high reaction is better suited. Generally, we find good agreement between system, if...

Hanbury-Brown-Twiss (HBT) correlations for charged pions in central Au+Au collisions at $\sqrt{s_\mathrm{NN}}=2.4 - 7.7~\text{GeV}$ (corresponding to beam kinetic energies the fixed target frame from $E_{\rm{lab}}=1.23~\text{to}~30~\text{GeV/nucleon}$) are calculated using UrQMD model with different equations of state. The effects a phase transition high baryon densities clearly observed HBT parameters that explored. It is found available data on radii, $R_{O}/R_{S}$ and...

Isospin triggering allows to distinguish coalescence from thermal production of light clusters in heavy ion collisions. Triggering on $Y(π^-) - Y(π^+)$ select very neutron or proton rich final states. The deuteron (cluster) with ($d \propto n \cdot p$) leads then an inverse parabolic dependence the yield $ΔY_π$. In contrast, a model, cluster is independent observation maximum as function $ΔY_π$ provides confirmation mechanism.

We investigate the coalescence factors $B_2$ and $B_3$ at low collision energies ($\sqrt{s_\mathrm{NN}}<6$ GeV) with special focus on HADES RHIC-BES experiments. It is shown that, in order to properly interpret $B_A$, two important corrections are necessary: I) has be calculated using proton $\times$ neutron yields denominator, instead of square yield, II) primordial (neutron) densities have used for normalization not final state (free) protons (neutrons). Both effects lead a drastic...