Nuclear Theory·nucl-th

Friday·February 16, 2024

4 papers—3 primary·1 cross-listed

01
[Submitted on 14 Feb 2024]
Nonmonotonic specific entropy on the transition line near the QCD critical point
Maneesha Sushama Pradeep🇺🇸 · Noriyuki Sogabe🇺🇸 · Mikhail Stephanov🇺🇸 · Ho-Ung Yee🇺🇸
We investigate the effect of the quantum chromodynamics (QCD) critical point on the isentropic trajectories in the QCD phase diagram. We point out that the universality of the critical equation of state and the third law of thermodynamics require the specific entropy (per baryon) along the coexistence (first-order transition) line to be nonmonotonic at least on one side of that line. Specifically, a maximum must occur. We show how the location of the maximum relative to the QCD critical point depends on the parameters of the critical equation of state commonly used in the literature. We then examine how the isentropic trajectories followed by adiabatically expanding heavy-ion collision fireballs behave near the critical point. We find that a crucial role is played by the sign of the isochoric temperature derivative of pressure at the critical point; this sign determines on which side of the coexistence curve the specific entropy must be nonmonotonic (i.e., has a maximum). We classify different scenarios of the adiabatic expansion that arise depending on the value of the discriminant parameter and the proximity of the trajectory to the critical point.
Comments:
22 pages, 13 figures; published version
Subjects:
Nuclear Theory (nucl-th); Statistical Mechanics (cond-mat.stat-mech); High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2402.09519 [pdf]
PRC(2024)·17 citations
02
[Submitted on 14 Feb 2024]
Hydrodynamization and resummed viscous hydrodynamics
Michael Strickland🇺🇸
In this contributed chapter, I review our current understanding of the applicability of hydrodynamics to modeling the quark-gluon plasma (QGP), focusing on the question of hydrodynamization/thermalization of the QGP and the anisotropic hydrodynamics (aHydro) far-from-equilibrium hydrodynamic framework. I discuss the existence of far-from-equilibrium hydrodynamic attractors and methods for determining attractors within different hydrodynamical frameworks. I also discuss the determination of attractors from exact solutions to the Boltzmann equation in relaxation time approximation and effective kinetic field theory applied to quantum chromodynamics. I then present comparisons of the kinetic attractors with the attractors obtained in standard second-viscous hydrodynamics frameworks and anisotropic hydrodynamics. I demonstrate that, due to the resummation of terms to all orders in the inverse Reynolds number, the anisotropic hydrodynamics framework can describe both the weak- and strong-interaction limits. I then review the phenomenological application of anisotropic hydrodynamics to relativistic heavy-ion collisions using both quasiparticle aHydro and second-order viscous aHydro. The phenomenological results indicate that aHydro provides a controlled extension of dissipative relativistic hydrodynamics to the early-time far-from-equilibrium stage of heavy-ion collisions. This allows one to better describe the data and to extract the temperature dependence of transport coefficients at much higher temperatures than linearized second-order viscous hydrodynamics.
Comments:
68 pages, 25 figures; Contributed chapter to Quark-Gluon Plasma 6 book
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2402.09571 [pdf]
IJMPE(2024)·14 citations
03
[Submitted on 15 Feb 2024]
The QCD phase diagram and Beam Energy Scan physics: a theory overview
Lipei Du🇨🇦 · Agnieszka Sorensen🇺🇸 · Mikhail Stephanov🇺🇸
We review recent theoretical developments relevant to heavy-ion experiments carried out within the Beam Energy Scan program at the Relativistic Heavy Ion Collider. Our main focus is on the description of the dynamics of systems created in heavy-ion collisions and establishing the necessary connection between the experimental observables and the QCD phase diagram.
Comments:
v1: 105 pages + 33 pages references, 24 figures; v2: 142 pages. A chapter contribution to book Quark-Gluon Plasma 6
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2402.10183 [pdf]
IJMPE(2024)·93 citations
04
[Submitted on 15 Feb 2024] (cross-list from hep-ph)
Constraints on the Variation of Physical Constants, Equivalence Principle Violation, and a Fifth Force from Atomic Experiments
V. A. Dzuba🇦🇺 · V. V. Flambaum🇦🇺 · A. J. Mansour🇦🇺
The aim of this paper is to derive limits on various forms of ``new physics'' using atomic experimental data. Interactions with dark energy and dark matter fields can lead to space-time variations of fundamental constants, which can be detected through atomic spectroscopy. In this study, we examine the effects of a varying nuclear mass $m_{N}$ and nuclear radius $r_{N}$ on two transition ratios: the comparison of the two-photon transition in atomic hydrogen with the hyperfine transition in $^{133}$ Cs based clocks, and the ratio of optical clock frequencies in in Al $^{+}$ and Hg $^{+}$ . The sensitivity of these frequency ratios to changes in $m_{N}$ and $r_{N}$ enables us to derive new limits on the variations of the proton mass, quark mass, and the QCD parameter $θ$ . Additionally, we consider the scalar field generated by the Yukawa-type interaction of feebly interacting hypothetical scalar particles with Standard Model particles in the presence of massive bodies such as the Sun and Moon. Using the data from the Al $^{+}$ /Hg $^{+}$ , Yb $^{+}$ /Cs and Yb $^{+}$ (E2)/Yb $^{+}$ (E3) transition frequency ratios, we place constraints on the interaction of the scalar field with photons, nucleons, and electrons for a range of scalar particle masses. We also investigate limits on the Einstein Equivalence Principle (EEP) violating term ( $c_{00}$ ) in the Standard Model Extension (SME) Lagrangian and the dependence of fundamental constants on gravity.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th); Atomic Physics (physics.atom-ph)
arXiv:
2402.09643 [pdf]
PRD(2024)·13 citations

Affiliations

first authorsco-authorsvia INSPIRE

Nonmonotonic specific entropy on the transition line near the QCD critical point

Hydrodynamization and resummed viscous hydrodynamics

The QCD phase diagram and Beam Energy Scan physics: a theory overview

Constraints on the Variation of Physical Constants, Equivalence Principle Violation, and a Fifth Force from Atomic Experiments

Affiliations