Scrutinizing the η η' mixing, masses and pseudoscalar decay constants in the framework of U(3) chiral effective field theory
Abstract
We study the η η' mixing up to nexttonexttoleadingorder 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 higherderivative, kinematic and mass mixing terms, is addressed. The connections between the four mixing parameters in the twomixingangle scheme and the low energy constants in the U(3) chiral effective theory are provided both for the singletoctet and the quarkflavor bases. The axialvector decay constants of pion and kaon are studied in the same order and confronted with the lattice simulation data as well. The quarkmass dependences of m _{ η }, m _{ η '} and m _{ K } are found to be well described at nexttoleading 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 nexttonexttoleading 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.
 Publication:

Journal of High Energy Physics
 Pub Date:
 June 2015
 DOI:
 10.1007/JHEP06(2015)175
 arXiv:
 arXiv:1503.02248
 Bibcode:
 2015JHEP...06..175G
 Keywords:

 Effective field theories;
 Chiral Lagrangians;
 High Energy Physics  Phenomenology;
 High Energy Physics  Experiment;
 High Energy Physics  Lattice;
 Nuclear Theory
 EPrint:
 29 pages, 5 figures. Updated numerical results. References added. To match the published version in JHEP