專題演講 Seminar

2023/06/30(Fri)     11:00 -12:00   
視訊演講 Video Seminar [ Meeting Link / ID: 2518 616 4236 / Password: FridaySeminar23 ]

Title

How baryons appear in low-energy QCD: Domain-wall skyrmion phase in strong magnetic fields

Speaker

Dr. Kentaro Nishimura (Keio University)

Abstract

Low-energy dynamics of QCD can be described by pion degrees of freedom in terms of the chiral perturbation theory (ChPT). A chiral soliton lattice (CSL), an array of solitons, is the ground state due to the chiral anomaly in the presence of a magnetic field larger than a certain critical value at finite density.
Here, we show in a model-independent and fully analytic manner (at the leading order of ChPT) that the CSL phase transits to a domain-wall skyrmion phase when the chemical potential is larger than the critical value μ_c = 16π f_π^⅔ m_π ~ 1.03 GeV with the pion's decay constant f_π and mass m_π, which can be regarded as the nuclear saturation density. There spontaneously appear stable two-dimensional skyrmions or lumps on a soliton surface, which can be viewed as three-dimensional skyrmions carrying even baryon numbers from the bulk despite no skyrme term. They behave as superconducting rings with persistent currents due to a charged pion condensation, and areas of the rings' interiors are quantized. This phase is in the scope of future heavy-ion collider experiments. This talk is based on arXiv:2304.02940.

Language

演講語言 (Language): in English