RT Journal Article T1 Patterns and partners for chiral symmetry restoration A1 Gómez Nicola, Ángel A1 Ruiz De Elvira Carrascal, Jacobo AB We present and analyze a new set of Ward Identities which shed light on the distinction between different patterns of chiral symmetry restoration in QCD, namely O(4) vs O(4) x U(1)_A. The degeneracy of chiral partners for all scalar and pseudoscalar meson nonet members is studied through their corresponding correlators. Around chiral symmetry degeneration of O(4) partners, our analysis predicts that U(1)_A partners are also degenerated. Our analysis also leads to I = 1/2 scalar-pseudoscalar partner degeneration at exact chiral restoration and supports ideal mixing between the η- η' and the f₀(500)-f₀(980) mesons at O(4) x U(1)_A restoration, with a possible range where the pseudoscalar mixing vanishes if the two transitions are well separated. We test our results with lattice data and provide further relevant observables regarding chiral and U(1)_A restoration for future lattice and model analyses. PB Amer Physical Soc SN 2470-0010 YR 2018 FD 2018-04-16 LK https://hdl.handle.net/20.500.14352/12156 UL https://hdl.handle.net/20.500.14352/12156 LA eng NO © Amer Physical Soc.We thank Z. H. Guo, L. Tunstall, S. Sharma, and O. Phillipsen for helpful discussions. A. G. N. is very grateful to the AEC and the ITP in Bern for their hospitality and financial support. Work was partially supported by research Contracts No. FPA2014-53375-C2-2-P, FIS2014- 57026-REDT, and FPA2016-75654-C2-2-P (spanish “Ministerio de Economía y Competitividad”), the DFG (SFB/TR 16, “Subnuclear Structure of Matter”), and the Swiss National Science Foundation. NO Ministerio de Economía y Competitividad (MINECO) NO ITP in Bern NO DFG NO Swiss National Science Foundation DS Docta Complutense RD 9 abr 2025