Abstract
Using of data taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we study the semileptonic decays and . We measure the absolute decay branching fractions and , where the first uncertainties are statistical and the second systematic. We also measure the differential decay rates and study the form factors of these two decays. With the values of and from Particle Data Group fits assuming Cabibbo-Kobayashi-Maskawa (CKM) unitarity, we obtain the values of the form factors at , , and . Taking input from recent lattice QCD calculations of these form factors, we determine values of the CKM matrix elements and , where the third uncertainties are theoretical.
- Received 27 March 2017
DOI:https://doi.org/10.1103/PhysRevD.96.012002
© 2017 American Physical Society