The strong vertices of bottom mesons $B$, $B^{\ast }$ and bottomonia ${\rm Y}$, ${\eta }_b$

Abstract

In this article, the strong coupling constants of vertices $BB{\rm Y}$, $B{B}^{\ast }{\rm Y}$, $B^{\ast }{B}^{\ast }{\rm Y}$, $B{B}^{\ast }{\eta }_b$ and $B^{\ast }{B}^{\ast }{\eta }_b$ are analyzed in the framework of QCD sum rules. In this work, all possible off-shell cases and the contributions of vacuum condensate terms including $⟨\overline{q}q⟩$, $⟨\overline{q}{g}_s\sigma Gq⟩$, $⟨g_s^2{G}^2⟩$, $⟨f^3{G}^3⟩$ and $⟨\overline{q}q⟩⟨g_s^2{G}^2⟩$ are considered. The momentum dependent strong coupling constants are first calculated and then are fitted into analytical functions $g(Q^2)$ which are used to extrapolate into time-like regions to obtain the final values of strong coupling constants. The final results are $g_{BB{\rm Y}}=40.67_{-4.20}^{+7.55}$, $g_{B{B}^{\ast }{\rm Y}}=11.58_{-1.09}^{+2.19}$ GeV${}^{-1}$, $g_{B^{\ast }{B}^{\ast }{\rm Y}}=57.02_{-5.31}^{+5.32}$, $g_{B{B}^{\ast }{\eta }_b}=23.39_{-2.30}^{+4.74}$ and $g_{B^{\ast }{B}^{\ast }{\eta }_b}=12.49_{-1.35}^{+2.12}$ GeV${}^{-1}$. These strong coupling constants are important input parameters which reflect the dynamic properties of the interactions among the mesons and quarkonia.

Comments: arXiv admin note: text overlap with arXiv:2304.13969