arXiv subjects

A. Cerqueira Jr

Publications and source records attributed to A. Cerqueira Jr.

3 recordsLinked to original sources

arXiv2021

The $D_sDK^*$ vertex in QCD Sum Rules: form factors and coupling constant

In this work we study the meson vertex $D_sDK^*$ using the QCD sum rules. We compute the three point correlation functions for the three cases of different off-shell mesons. The form factors for each case are fitted to the numerical calculation of the correlation functions and the coupling constant of the vertex is obtained by comparing the form factors at their respective off-shell meson pole. The result obtained for the coupling constant is $g_{D_sDK^*} = 2.29^{+0.65}_{-0.41}$.

hep-ph↗

arXiv2015

A QCD sum rules calculation of the $J/ψD_s^* D_s$ strong coupling constant

In this work, we calculate the form factors and the coupling constant of the strange-charmed vertex $J/ψD_s^* D_s$ in the framework of the QCD sum rules by studying their three-point correlation functions. All the possible off-shell cases are considered, $D_s$, $D_s^*$ and $J/ψ$, resulting in three different form factors. These form factors are extrapolated to the pole of their respective off-shell mesons, giving the same coupling constant for the process. Our final result for the $J/ψD_s^* D_s$ coupling constant is $g_{J/ψD^*_s D_s} = 4.30^{+0.42}_{-0.37}\text{GeV}^{-1}$.

hep-ph↗

arXiv2011

$B_s^* B K$ vertex from QCD sum rules

The form factors and the coupling constant of the $B_s^* B K$ vertex are calculated using the QCD sum rules method. Three point correlation functions are computed considering both $K$ and $B$ mesons off-shell and, after an extrapolation of the QCDSR results, we obtain the coupling constant of the vertex. We study the uncertainties in our result by calculating a third form factor obtained when the $B^*_s$ is the off-shell meson, considering other acceptable structures and computing the variations of the sum rules' parameters. The form factors obtained have different behaviors but their simultaneous extrapolations reach to the same value of the coupling constant $g_{B_s^* B K}=10.6 \pm 1.7$. We compare our result with other theoretical estimates.

hep-ph↗