Key points are not available for this paper at this time.
Analyzing e^+e^- collision data corresponding to an integrated luminosity of 7. 33~fb^-1 collected at center-of-mass energies between 4. 128 and 4. 226~GeV with the BESIII detector, we measure the branching fraction of the semileptonic decay D^+ₒ K⁰ e^+ₑ to be (2. 980. 230. 12) 10^-3. The Dₛ^+ K⁰ hadronic form factor is determined from the differential decay rate of D^+ₛ K⁰ e^+ₑ to be f^K⁰_+ (0) =0. 6360. 0490. 013. For both measurements, the first uncertainty is statistical and the second systematic. The branching fraction and form factor measurements are factors of 1. 6 and 1. 7 more precise than the previous world averages, respectively.
Collaboration et al. (2024) studied this question.