$B_s B^* K $ and $B_s B K^*$ vertices using QCD sum rules

TL;DR

This paper calculates the coupling constants for specific meson vertices using QCD sum rules, providing new theoretical estimates and analyzing uncertainties in the results.

Contribution

It introduces a detailed QCD sum rules approach to determine coupling constants for $B_s B^* K$ and $B_s B K^*$ vertices, including off-shell effects and uncertainty analysis.

Findings

Coupling constant for $B_s B^* K$ is $8.41 \\pm 1.23$

Coupling constant for $B_s B K^*$ is $3.3 \\pm 0.5$

Results agree with other theoretical estimates

Abstract

The form factors and the coupling constant of the $B_s B^* K $ and $B_s B K^*$ vertices are calculated using the QCD sum rules method. Three point correlation functions are computed considering both the heavy and light mesons off-shell in each vertex, from which, after an extrapolation of the QCDSR results at the pole of the off-shell mesons, we obtain the coupling constant of the vertex. The form factors obtained have different behaviors but their simultaneous extrapolation reach the same value of the coupling constant $g_{B_s B^* K}=8.41 \pm 1.23 $ and $g_{B_s BK^*}=3.3 \pm 0.5$. We compare our result with other theoretical estimates and compute the uncertainties of the method.