Calculation of coupling constants and decay width

In this research paper, we evaluate the strong coupling constants of the K
Kπ, ϕKK, ϕK
K
and ρK
K
vertices in the framework of the three-point QCD sum rules. In each vertex two different off-shell particles are considered and the final results are compared to the other existing predictions. We study the decay width of K
→ Kπ and ϕ → KK and obtain the values ΓðK
→ KπÞ ¼ 46.8 and Γðϕ → KKÞ ¼ 5.58, which have good agreement with experimental values.

Coupling constant, decay width, QCD sum rules, light mesons