Semileptonic decay of Bc meson into S wave charmonium in a QCD potential model with coulombic part as perturbation

We present the semileptonic decay of $B_{c}$ meson in a QCD potential model with the coulombic part of the Cornell potential $-\frac{4\alpha_{S}}{3r}+br+c$ as perturbation. Computing the slope and curvature of Isgur Wise function in this approach, we study the pseudoscalar and vector form factors for the transition of $B_{c}$ meson to its S wave charmonium $c\bar{c}$ states. Numerical estimates of widths for the transitions of $B_{c}\rightarrow J/\psi(\eta_{c})l\nu_{l}$ are presented. The results are found to be in good agreement with other theoretical values.