Relations among B c → J/ψ, η c form factors

Abstract

Abstract We analyze the form factors parametrizing the B c → J/ψ, η c matrix elements of the operators in a generalized low-energy b → c semileptonic Hamiltonian. We consider an expansion in nonrelativistic QCD, classifying the heavy quark spin symmetry breaking terms and expressing the form factors in terms of universal functions in a selected kinematical range. Using as an input the lattice QCD results for the B c → J/ψ matrix element of the SM operator, we obtain information on other form factors. The extrapolation to the full kinematical range is also presented.

Keywords

• Bottom Quarks
• Hadronic Matrix Elements and Weak Decays
• Semi-Leptonic Decays