2025/10/11 by Arthur E. B. Pasqualotto, Anonymous, Pasqualotto, Arthur E. B. +6 · 1 citation
Physics and Astronomy · #Chiral perturbation theory #Diquark #High-Energy Particle Collisions Research #Lattice (music) #Perturbation (astronomy) #Perturbation theory (quantum mechanics) #Pulsars and Gravitational Waves Research #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark
paper · pdf · open access · doi:10.1103/m9xd-3x6n
published in Physical review. D/Physical review. D. 113(3) (American Physical Society)
openalex created_date 2025/10/15 · openalex publication_date 2026/01/20 · openalex updated_date 2026/08/05
Lattice simulations of two-color, two-flavor quantum chromodynamics (QCD) at finite quark chemical potential have revealed a distinctive peak structure in the sound velocity. Although chiral perturbation theory (ChPT) and the Nambu-Jona-Lasinio (NJL) model have been employed to explain this phenomenon, neither approach has fully captured the observed behavior. To address this discrepancy, we have extended the NJL framework by incorporating the medium separation scheme (MSS). This approach isolates medium contributions from divergent integrals, allowing for a more accurate treatment of finite-density effects. Our results indicate a clear increase in the diquark gap ( <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mi mathvariant="normal">Δ</a:mi> </a:math> ) with increasing chemical potential, consistent with what is also seen in perturbative QCD predictions at high densities. Furthermore, the MSS-modified NJL model successfully reproduces the observed peak in the sound velocity.