The role of strangeness in chiral and U(1)A restoration

© The Author(s) 2021 We use recently derived Ward identities and lattice data for the light- and strange-quark condensates to reconstruct the scalar and pseudoscalar susceptibilities (chi S kappa, chi PK) in the isospin 1/2 channel. We show that chi S kappa develops a maximum above the QCD chiral tr...

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Detalles Bibliográficos
Autores: Gómez Nicola, Ángel, Ruiz De Elvira Carrascal, Jacobo, Vioque Rodríguez, Andrea, Álvarez Herrero, D.
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/4466
Acceso en línea:https://hdl.handle.net/20.500.14352/4466
Access Level:acceso abierto
Palabra clave:51-73
Symmetry restoration
Sigma-meson
QCD
Pion
Transition
Scattering
Resonance
Phase
Roy.
Física-Modelos matemáticos
Física matemática
Descripción
Sumario:© The Author(s) 2021 We use recently derived Ward identities and lattice data for the light- and strange-quark condensates to reconstruct the scalar and pseudoscalar susceptibilities (chi S kappa, chi PK) in the isospin 1/2 channel. We show that chi S kappa develops a maximum above the QCD chiral transition, after which it degenerates with chi PK. We also obtain chi S kappa within Unitarized Chiral Perturbation Theory (UChPT) at finite temperature, when it is saturated with the K0(700) (or kappa) meson, the dominant lowest-energy state in the isospin 1/2 scalar channel of pi K scattering. Such UChPT result reproduces the expected peak structure, revealing the importance of thermal interactions, and makes it possible to examine the chi S kappa dependence on the light- and strange-quark masses. A consistent picture emerges controlled by the ml/ms ratio that allows one studying K-kappa degeneration in the chiral, two-flavor and SU(3) limits. These results provide an alternative sign for O(4)xU(1)A restoration that can be explored in lattice simulations and highlight the role of strangeness, which regulated by the strange-quark condensate helps to reconcile the current tension among lattice results regarding U(1)A restoration.