An improved calculation of the $$D_{(s)}^*D_{(s)}V$$ and $$B_{(s)}^*B_{(s)}V$$ couplings from light-cone sum rules

Abstract

AbstractWe present an improved calculation of the $$D_{(s)}^*D_{(s)}V$$ D ( s ) ∗ D ( s ) V and $$B_{(s)}^*B_{(s)}V$$ B ( s ) ∗ B ( s ) V coupling constants, where V denotes $$\rho $$ ρ , $$K^*$$ K ∗ , $$\omega $$ ω , and $$\phi $$ ϕ mesons. These couplings govern the long-distance quantum chromodynamics (QCD) in interactions between heavy pseudo-scalar/vector mesons and light vector mesons. Our analysis is conducted within the framework of QCD light-cone sum rules (LCSRs) by utilizing the light-cone distribution amplitudes (LCDAs) of light vector mesons. By systematically incorporating the subleading power corrections and higher-twist contributions at the leading order (LO) and including the next-to-leading order (NLO) corrections at leading power, we achieve enhanced accuracy in the light-cone operator product expansion (OPE) for the underlying correlation function. In assessing the reliability of the established LCSRs, we consider uncertainties arising from the choice of the quark–hadron duality region in the double dispersion relation. Building upon these improvements, we accomplish an optimized computation and analysis for the strong coupling constants $$g_{H^*HV}$$ g H ∗ H V which are used to extract the effective coupling $$\lambda $$ λ in the heavy meson chiral perturbation theory (HM$$\chi $$ χ PT). Furthermore, we investigate the SU(3) flavor symmetry-breaking effects in detail and compare our sum rule calculations with previous studies in an exploratory way.