Abstract
We analyze the form factors parametrizing the Bc → J/ψ, ηc 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 Bc → 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.
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Colangelo, P., De Fazio, F., Loparco, F. et al. Relations among Bc → J/ψ, ηc form factors. J. High Energ. Phys. 2022, 28 (2022). https://doi.org/10.1007/JHEP09(2022)028
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DOI: https://doi.org/10.1007/JHEP09(2022)028