Scrutinizing the η-η′ mixing, masses and pseudoscalar decay constants in the framework of U(3) chiral effective field theory

Abstract

Abstract:We study the η-η ′ mixing up to next-to-next-to-leading-order in U(3) chiral perturbation theory in the light of recent lattice simulations and phenomenological inputs. A general treatment for the η-η ′ mixing at higher orders, with the higher-derivative, kinematic and mass mixing terms, is addressed. The connections between the four mixing parameters in the two-mixing-angle scheme and the low energy constants in the U(3) chiral effective theory are provided both for the singlet-octet and the quark-flavor bases. The axial-vector decay constants of pion and kaon are studied in the same order and confronted with the lattice simulation data as well. The quark-mass dependences of m η , m η ′ and m K are found to be well described at next-to-leading order. Nonetheless, in order to simultaneously describe the lattice data and phenomenological determinations for the properties of light pseudoscalars π, K, η and η ′ , the next-to-next-to-leading order study is essential. Furthermore, the lattice and phenomenological inputs are well reproduced for reasonable values of low the energy constants, compatible with previous bibliography.

Study of theKN−K*Ncoupled system ins-wave

“…One possibility is to consider contributions from higher order terms of the Lagrangian (like Refs. [62,63]). While that would imply fixing a large number of parameters with scarce data available, it is wiser and important to exhaust possible corrections to be included while keeping the lowest order contribution for the KN system.…”

Study on the radiative decays of $$h_c$$ h c via intermediate meson loops model

“…In Ref. [75], the authors studied the η-η mixing up to next-to-next-to-leading order in U(3) chiral perturbation theory in the light of recent lattice simulations and phenomenological inputs. Within the framework of the effective Lagrangian approach, the authors perform a thorough analysis of the J/ψ → V P, J/ψ → γ P together with a few other processes to investigate this mixing problem [76].…”

Updated study of the η−η′ mixing and the thermal properties of light pseudoscalar mesons at low temperatures

“…New lattice results, including the pion-mass dependences of the mixing angles and decay constants in the quark-flavor basis, are considered, comparing with the study in Ref. [26]. After the determination of the Uð3Þ χPT LECs, we extend the discussions at zero temperature to the thermal medium with finite temperatures.…”

“…In Ref. [26], one of the authors performed a complete next-to-next-to-leading-order (NNLO) calculation of the masses and decay constants of the light pseudoscalar mesons within Uð3Þ χPT. In the present work we first update the previous study by taking into account several independent lattice simulation results, especially the sophisticated lattice simulations in Ref.…”