New Sum Rules for the $B_c\to J/\psi$ Form Factors

Marzia Bordone, Alexander Khodjamirian, Thomas Mannel

We derive new sum rules for the form factors of the $B_c\to J/\psi \ell {\bar{\nu }}_{\ell }$ semileptonic transitions, employing the vacuum-to-$B_c$ correlation function of the $J/\psi$-interpo…