nucl-th digest · Jul 8, 2022

[Submitted on 7 Jul 2022]

Structure formation during phase transitions in strongly interacting matter

A broad range of problems associated with phase transitions in systems characterized by the strong interaction between particles and with formation of structures is reviewed. A general phenomenological mean-field model is constructed describing phase transitions of the first and the second order to the $k_{0} = 0$ and $k_{0} \neq = 0$ states. Due to fluctuations, the phase transition to the state $k_{0} \neq = 0$ is the transition of the first order. Various specific features of the phase transitions to the state $k_{0} \neq = 0$ are considered such as the anisotropic spectrum of excitations, a possibility of the formation of various structures including running and standing waves, three-axis structures, chiral waves, pasta phases, etc. A formal transition to hydrodynamical variables is performed. Then focus is made on description of the dynamics of the order parameter at the phase transitions to the states with $k_{0} = 0$ and $k_{0} \neq = 0$ . Next the non-ideal hydrodynamical description of the phase transitions of the liquid-gas type in nuclear systems is performed. Quasiperiodic structures are developed. Next, pion condensation phase transition to the $k_{0} \neq = 0$ state in dense, cold or warm nuclear matter is considered and then the high temperature -- small baryon chemical potential system is studied, when baryons become completely blurred and light bosons, e.g., pions, may condense either in $k_{0} = 0$ or $k_{0} \neq = 0$ states. Then, for scalar collective modes phenomena of the Pomeranchuk instability and the Bose condensation in $k_{0} = 0$ or $k_{0} \neq = 0$ states are studied. Next, possibility of the condensation of Bose excitations in the $k_{0} \neq = 0$ state in moving media is considered. Then Bose-Einstein condensation of pions at dynamically fixed number of particles is studied and specific non-equilibrium effects are demonstrated on an example.

Comments:: 110pages, 13 figures
Subjects:: Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:: 2207.03212 [pdf]

PPNP(2023)·14 citations

Bayesian Inference of the Symmetry Energy and the Neutron Skin in

^{48}

Ca and

^{208}

Pb from CREX and PREX-2

Using the recent model-independent determination of the charge-weak form factor difference

Δ F_{CW}

^{48}

Ca and

^{208}

Pb by the CREX and PREX-2 collaborations together with some well-determined properties of doubly magic nuclei, we perform Bayesian inference of the symmetry energy

E_{sym} (ρ)

and the neutron skin thickness

Δ r_{np}

^{48}

Ca and

^{208}

Pb within the Skyrme energy density functional (EDF). We find the inferred

E_{sym} (ρ)

and

Δ r_{np}

separately from CREX and PREX-2 are compatible with each other at

90%

C.L., although they are inconsistent at

68.3%

C.L. with CREX (PREX-2) favoring a very soft (stiff)

E_{sym} (ρ)

and rather small (large)

Δ r_{np}

. By combining the CREX and PREX-2 data, we obtain a soft symmetry energy around saturation density

ρ_{0}

and thinner

Δ r_{np}

^{48}

Ca and

^{208}

Pb, which are found to be closer to the corresponding results from CREX alone, implying the PREX-2 is less effective to constrain the

E_{sym} (ρ)

and

Δ r_{np}

due to its lower precision of

Δ F_{CW}

. Furthermore, we find the Skyrme EDF results inferred by combining the CREX and PREX-2 data nicely agree with the measured dipole polarizabilities

α_{D}

^{48}

Ca and

^{208}

Pb as well as the neutron matter equation of state from microscopic calculations. The implications of the inferred soft

E_{sym} (ρ)

around

ρ_{0}

are discussed.

Comments:: 8 pages, 7 figures, 3 tables. Significantly expanded to include many details and discussions. Accepted version to appear in PRC
Subjects:: Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:: 2207.03328 [pdf]

PRC(2023)·91 citations

Friday·July 8, 2022

Structure formation during phase transitions in strongly interacting matter

Bayesian Inference of the Symmetry Energy and the Neutron Skin in $^{48}$ Ca and $^{208}$ Pb from CREX and PREX-2

Affiliations

Structure formation during phase transitions in strongly interacting matter

Bayesian Inference of the Symmetry Energy and the Neutron Skin in 48Ca and 208Pb from CREX and PREX-2

Affiliations

Bayesian Inference of the Symmetry Energy and the Neutron Skin in $^{48}$ Ca and $^{208}$ Pb from CREX and PREX-2