Decays of excited pseudoscalar and vector mesons in the chiralU(3) ×U(3) model

Two-photon decays and photoproduction on electrons ofη(550),η′(958),Arbuzov1, Волков2 2011Phys. Rev. CSelf Cite

“…It is worth to note that if we exclude from the consideration the excited states, we would get instead of the 4 × 4 matrix a simple 2×2 matrix corresponding to unitary orthogonal transformations with the standard singlet-octet mixing angle θ ≈ −19 • , see Ref. [20]. The latter quantity is close to the values of the mixing angle obtained in numerous theoretical and experimental studies, see e.g.…”

2γ decays of scalar mesons (σ(600), f 0(980), and a 0(980)) in the Nambu-Jona-Lasinio model

“…with the mixing angle α = 11.3 o [9,15,16]. The coupling constants from the Lagrangian (1) are defined in the following way [3]:…”

Low-energy interactions of mesons with participation of the first radially excited states in $U(3) \times U(3)$ NJL model

“…The formulated extended version of the NJL model made it possible to describe various low-energy meson interaction processes with the participation of radially excited states. A number of processes calculated in the extended model were described in detail in the review [33] and original papers [41][42][43]. Brief results of these calculations are presented in Table 2.…”