Improved measurements of D 0 → K − ℓ + ν ℓ and D + → K ¯ 0 ℓ + ν ℓ

• Published in: Physical review. D 2024-12, Vol.110 (11), Article 112006
• Main Authors: Ablikim, M., Achasov, M. N., Adlarson, P., Afedulidis, O., Ai, X. C., Aliberti, R., Amoroso, A., An, Q., Bai, Y., Bakina, O., Balossino, I., Ban, Y., Bao, H.-R., Batozskaya, V., Begzsuren, K., Berger, N., Berlowski, M., Bertani, M., Bettoni, D., Bianchi, F., Bianco, E., Bortone, A., Boyko, I., Briere, R. A., Brueggemann, A., Cai, H., Cai, X., Calcaterra, A., Cao, G. F., Cao, N., Cetin, S. A., Chai, X. Y., Chang, J. F., Che, G. R., Che, Y. Z., Chelkov, G., Chen, C., Chen, C. H., Chen, Chao, Chen, G., Chen, H. S., Chen, H. Y., Chen, M. L., Chen, S. J., Chen, S. L., Chen, S. M., Chen, T., Chen, X. R., Chen, X. T., Chen, Y. B., Chen, Y. Q., Chen, Z. J., Chen, Z. Y., Choi, S. K., Cibinetto, G., Cossio, F., Cui, J. J., Dai, H. L., Dai, J. P., Dbeyssi, A., de Boer, R. E., Dedovich, D., Deng, C. Q., Deng, Z. Y., Denig, A., Denysenko, I., Destefanis, M., De Mori, F., Ding, B., Ding, X. X., Ding, Y., Dong, J., Dong, L. Y., Dong, M. Y., Dong, X., Du, M. C., Du, S. X., Duan, Y. Y., Duan, Z. H., Egorov, P., Fan, Y. H., Fang, J., Fang, S. S., Fang, W. X., Fang, Y., Fang, Y. Q., Farinelli, R., Fava, L., Feldbauer, F., Felici, G., Feng, C. Q., Feng, J. H., Feng, Y. T., Fritsch, M., Fu, C. D., Fu, J. L., Fu, Y. W., Gao, H.
• Format: Article
• Language: English
• ISSN: 2470-0010; 2470-0029
• DOI: 10.1103/PhysRevD.110.112006

Using 7.93 fb − 1 of e + e − collision data collected at the center-of-mass energy of 3.773 GeV with the BESIII detector, we measure the absolute branching fractions of D 0 → K − e + ν e , D 0 → K − μ + ν μ , D + → K ¯ 0 e + ν e , and D + → K ¯ 0 μ + ν μ to be ( 3.521 ± 0.00 9 stat ± 0.01 6 syst ) % , ( 3.419 ± 0.01 1 stat ± 0.01 6 syst ) % , ( 8.864 ± 0.03 9 stat ± 0.08 2 syst ) % , and ( 8.665 ± 0.04 6 stat ± 0.08 4 syst ) % , respectively. By performing a simultaneous fit to the partial decay rates of these four decays, the product of the hadronic form factor f + K ( 0 ) and the modulus of the c → s Cabibbo-Kobayashi-Maskawa matrix element | V c s | is determined to be f + K ( 0 ) | V c s | = 0.7171 ± 0.001 1 stat ± 0.001 3 syst . Taking the value of | V c s | = 0.97349 ± 0.00016 from the standard model global fit or that of f + K ( 0 ) = 0.7452 ± 0.0031 from the lattice quantum chromodynamics calculation as input, we derive the results f + K ( 0 ) = 0.7366 ± 0.001 1 stat ± 0.001 3 syst . and | V c s | = 0.9623 ± 0.001 5 stat ± 0.001 7 syst ± 0.004 0 LQCD .