https://doi.org/10.1140/epjc/s10052-016-4424-y
Regular Article - Theoretical Physics
Semileptonic decays of 
meson to S-wave charmonium states in the perturbative QCD approach
1
College of Sciences, North China University of Science and Technology, Tangshan, 063009, China
2
College of Information Engineering, North China University of Science and Technology, Tangshan, 063009, China
* e-mail: jindui1127@126.com
Received:
5
March
2016
Accepted:
10
October
2016
Published online:
20
October
2016
Inspired by the recent measurement of the ratio of branching fractions to 
and 
final states at the LHCb detector, we study the semileptonic decays of meson to the S-wave ground and radially excited 2S and 3S charmonium states with the perturbative QCD approach. After evaluating the form factors for the transitions 
, where P and V denote pseudoscalar and vector S-wave charmonia, respectively, we calculate the branching ratios for all these semileptonic decays. The theoretical uncertainty of hadronic input parameters are reduced by utilizing the light-cone wave function for the meson. It is found that the predicted branching ratios range from 
up to 
and could be measured by the future LHCb experiment. Our prediction for the ratio of branching fractions 
is in good agreement with the data. For 
decays, the relative contributions of the longitudinal and transverse polarization are discussed in different momentum transfer squared regions. These predictions will be tested on the ongoing and forthcoming experiments.
© The Author(s), 2016
