First Amplitude Analysis of D0→K−π0e+νe and Observation of D0→K2∗(1430)−e+νe
Using 20.3 fb−1 of e+e− collision data collected by the BESIII detector, this paper presents the first amplitude analysis of the semileptonic decay D0→K−π0e+νe, leading to the first observation of a K2∗(1430)− component, precise measurements of hadronic form factors and branching fractions, and stringent tests of lepton flavor universality and isospin symmetry without finding any violations.
BESIII Collaboration, M. Ablikim, M. N. Achasov, P. Adlarson, X. C. Ai, R. Aliberti, A. Amoroso, Q. An, Y. Bai, O. Bakina, Y. Ban, H. R. Bao, V. Batozskaya, K. Begzsuren, N. Berger, M. Berlowski, M. B (…)2026-03-03⚛️ hep-ex