Study of theη-η′system in the two mixing angle scheme

Abstract

A two mixing angle description of the pseudoscalar decay constants associated to the η-η ′ system is used to parametrize the theoretical amplitudes of the radiative decays (η, η ′ ) → γγ and the coupling constants g V (η,η ′ )γ with V = ρ, ω, φ . The parametrization is performed in both the "octet-singlet" basis and the "quark-flavour" basis. An excellent agreement with the most recent experimental data is achieved. Our analysis reveals that at the present experimental accuracy the two mixing angles differ significantly in the former basis but not in the latter, in accordance with the expectations of large N c Chiral Perturbation Theory where the difference between the two mixing angles are due to a SU(3) f -breaking effect and a violation of the OZI rule respectively.

ηandη′ transition form factors from Padé approximants

“…In Fig. 2 we compare our determination (8) with different phenomenological results [5,6] and find a very good agreement even though we use a much smaller amount of inputs than Refs. [4][5][6].…”

“…This translates to F 8 /F π = 1.29(10), F 0 /F π = 1.19(6), θ 8 = −22.1(2.8) • , θ 0 = −8.1 (3.2) • in the octet-singlet basis [5,6]. In Fig.…”

B0→ωη(′)andϕη(′Guo1, Chen2, Xiao3 2007Phys. Rev. D220140View full textAdd to dashboardCite

“…The three input parameters f q , f s and φ in the quark-flavor basis have been extracted from various related experiments [21,22] …”

Branching ratio andCPasymmetry ofB0→η(′)ηXiao1, Guo2, Chen3 2007Phys. Rev. D22080View full textAdd to dashboardCite

“…in the quark model, and the two mixing angles θ 1 and θ 8 , in principle, can be determined by various related experiments [30,31]. In the numerical calculations, we will use the following η − η ′ mixing parameters [30] …”