Phase transitions and critical behavior in hadronic transport with a relativistic density functional equation of state
Agnieszka Sorensen, Volker Koch
备注:
31 pages, 14 figures. Revised version to be published in PRC (in press). We added a discussion of correlations in hadronic transport and improved the proof of the relationship between the second order cumulant and the pair distribution function at close distances
We develop a flexible, relativistically covariant parameterization of dense nuclear matter equation of state suited for inclusion in computationally demanding hadronic transport simulations. Within an implementation in the hadronic transport code SMASH, we show that effects due to bulk thermodynamic behavior are reproduced in dynamic hadronic systems, demonstrating that hadronic transport can be used to study critical behavior in dense nuclear matter, both at and away from equilibrium. We also show that two-particle correlations calculated from hadronic transport simulation data follow theoretical expectations based on the second order cumulant ratio, and constitute a clear signature of crossing the phase diagram above the critical point.
A class of phenomenological relativistic models of hadronic systems motivated by QCD that have dual representations as models of mesons and nucleons or quarks and gluons is investigated. These models are designed to provided qualitative insight into the role of sea quarks in hadronic structure and reactions. The model assumption is that the Hamiltonian can be divided into two parts; one that involves degrees of freedom in the same connected local and global color singlet and the remaining interactions that allow the connected local and global color singlets to interact. The first class of inte…
Electric charge transport of hadronic matter at finite temperature and magnetic field is studied within the linear sigma model. Anisotropic transport coefficients associated with the charge transport are estimated both in the weak and strong regimes of the magnetic field using the transport theory approach. In a weakly magnetized medium, the magnetic field effects are incorporated through the Lorentz force term in the Boltzmann equation. Strong magnetic field puts further constraints on the motion of charged particles through Landau quantization. Magnetic field-dependent thermal relaxation tim…
Accessing Exotic Hadronic States via Charmed-Meson Femtoscopy in Relativistic Heavy-Ion Collisions
Helmholtz Research Academy Hesse for FAIR (HFHF)(黑森FAIR亥姆霍兹研究学院);GSI Helmholtz Center for Heavy Ion Physics(GSI重离子物理亥姆霍兹中心);Institut für Theoretische Physik, Johann Wolfgang Goethe-Universität(约翰·沃尔夫冈·歌德大学理论物理研究所);GSI Helmholtzzentrum für Schwerionenforschung GmbH(GSI重离子研究亥姆霍兹有限公司);SUBATECH, Nantes University, IMT Atlantique, IN2P3/CNRS(南特大学SUBATECH实验室(隶属于IMT大西洋、IN2P3/CNRS));Frankfurt Institute for Advanced Studies(法兰克福高等研究院)
We investigate hadronic particle spectra and flow characteristics of heavy-ion reactions in the FAIR/NICA energy range of $1\ A{\rm GeV} \le E_{\rm lab} \le 10\ A{\rm GeV}$ within a relativistic ideal hydrodynamic one-fluid approach. The particlization is realized by sampling the Cooper-Frye distribution for a grand canonical hadron gas on a hypersurface of constant energy density. Results of the hydrodynamic calculations for different underlying equations of state are presented and compared with experimental data and microscopic transport simulations. The sensitivity of the approach to physic…
Based on the extended hadronic transport model of relativistic heavy-ion collisions, the incompressibility of dense hadronic matter created in relativistic Au+Au heavy-ion collisions at $\sqrt{s_{NN}} = 3$ GeV is studied. By comparing experimental proton directed flow, productions of strange hadrons $ϕ$, $K^{-}$ as well as their ratio $ϕ/K^{-}$, proton high-order cumulants to the model calculations, a large incompressibility of dense hadronic matter is obtained from nucleon observabels while a rather small incompressibility is needed to fit the data of strange hadrons. This may indicate hadron…
Role of event multiplicity on hadronic phase lifetime and QCD phase boundary in ultrarelativistic collisions at energies available at the BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider
In this paper we investigate the photoproduction of QED bound states in proton -- proton, proton -- nucleus and nucleus -- nucleus collisions at RHIC, LHC and FCC energies considering an accurate treatment of the absorptive corrections and for the nuclear form factor. The total cross sections for the production of singlet and triplet $(l^+ l^-)$ states, with $l = e,\, μ, \, τ$, are estimated and a detailed analysis of the photoproduction of singlet QED bound states is performed considering the rapidity ranges covered by central and forward detectors. The impact of the Coulomb corrections on th…
Relativistic Heavy-Ion Collisions within 3-Fluid Hydrodynamics: Hadronic Scenario
介绍了一个用于模拟相对论重离子碰撞的三流体动力学模型。除了两个重子丰富的流体,新模型考虑了第三个新产生的粒子的重子自由(即零重子净电荷)流体的延迟演化。它的演化是延迟的,由于形成时间,在此期间,重子自由流体既不热化,也不与重子丰富的流体相互作用。形成后,它开始与富含重子的流体相互作用,并迅速热化。在此模型下,采用纯强子状态方程,系统地分析了入射能量在几到160 AGeV之间的各种观测量,并与输运模型的结果进行了比较。在入射能量为E_{lab} =(1-160)AGeV的范围内,我们成功地合理地再现了大量的实验数据。该列表包括质子和π介子快度分布,质子横向质谱,λ和反λ超子的快度分布,质子和π介子的椭圆流(40 A GeV的质子v2除外),π介子的多重性,正K介子,φ介子,超子和反超子,包括多奇异粒子。与强子自由截面的估计结果相比,这种一致是以显著增强流间摩擦为代价的。但是,我们也发现了一些问题。K^-的计算产率比实验值高出约1.5倍。在E_{lab} > 40 A GeV时,我们也未能描述质子和π介子的定向横向流动。这种失效显然表明所用的EoS太硬,从而为相变留下了空间。
We investigate general frameworks for calculating transport coefficients for quasiparticle theories at finite temperature. Hadronic transport coefficients are then computed using the linear sigma model (LSM). The bulk viscosity over entropy density ($ζ/s$) is evaluated in the relaxation time approximation (RTA) and the specific shear viscosity ($η/s$) and static electrical conductivity ($σ_{el}/T$) are both obtained in the RTA and using a functional variational approach. Results are shown for different values of the scalar-isoscalar hadron vacuum mass with in-medium masses for the interacting …
We calculate the transport coefficients like shear viscosity and electrical conductivity with respect to density of dense hadronic and quark matter. By considering the simple massless limit for the quark matter and two different effective models for the hadronic matter, we have estimated the transport coefficients of the two phases separately. We have sketched the density profile of the transport coefficients in two parts viz. the phase-space part and the relaxation time part. By calculating the shear viscosity to density ratio, we have also explored the nearly perfect fluid domain of the quar…