QCD at finite isospin density: Chiral perturbation theory confronts lattice data

2019/09/30 by Prabal Adhikari, Jens O. Andersen · 43 citations
Physics and Astronomy · #Chiral perturbation theory #Diffraction #Flavor #High-Energy Particle Collisions Research #Isospin #Lattice (music) #Lattice QCD #Lattice constant #Lattice field theory #Observable #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #hep-ph #nucl-th

paper · pdf · doi:10.1016/j.physletb.2020.135352

published in Physics Letters B 804, 135352 (Elsevier BV) · 8 pages and 4 figs. v2: Expanded discussion, in particular the matching between two- and three flavor couplings for large strange-quark masses. Matches published version

openalex publication_date 2020/03/10 · arxiv created 2020/05/29 · arxiv updated 2020/06/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We consider the thermodynamics of three-flavor QCD in the pion-condensed phase at nonzero isospin chemical potential (μI) and vanishing temperature using chiral perturbation theory in the isospin limit. The transition from the vacuum phase to a superfluid phase with a Bose-Einstein condensate of charged pions is shown to be second order and takes place at μI=mπ. We calculate the pressure, isospin density, and energy density to next-to-leading order in the low-energy expansion. Our results are compared with recent high-precision lattice simulations as well as previously obtained results in two-flavor chiral perturbation theory. The agreement between the lattice results and the predictions from three-flavor chiral perturbation theory is very good for μI<200 MeV. For larger values of μI, the agreement between lattice data and the two-flavor predictions is surprisingly good and better than with the three-flavor predictions. Finally, in the limit ms≫mu=md, we show that the three-flavor observables reduce to the two-flavor observables with renormalized parameters. The disagreement between the results for two-flavor and three-flavor χPT can largely be explained by the differences in the measured low-energy constants.

Citations

• Phase diagram of dynamical twisted-mass Wilson fermions at finite isospin chemical potential
• Thermal pions at a finite isospin chemical potential
• Fate of pion condensation in quark matter: From the chiral limit to the physical pion mass
• Chiral perturbation theory to one loop
• The phase diagram of dense QCD
• Flavor-mixing effects on the QCD phase diagram at non-vanishing isospin chemical potential: one or two phase transitions?
• Chiral perturbation theory: Expansions in the mass of the strange quark
• QCD at Finite Isospin Density
• Pion superfluidity and meson properties at finite isospin density
• Pion condensation in electrically neutral cold matter with finite baryon density
• Color superconductivity in dense quark matter
• QCD phase diagram for nonzero isospin-asymmetry
• Multicomponent meson superfluids in chiral perturbation theory
• Phenomenological Lagrangians

Cited by

• Condensates and pressure of two-flavor chiral perturbation theory at nonzero isospin and temperature