https://doi.org/10.1140/epjc/s10052-023-12034-4
Regular Article - Theoretical Physics
Semileptonic decays 
meson to S-wave charmonia and X(3872) within the covariant light-front approach
1
Institute of Theoretical Physics, School of Sciences, Henan University of Technology, 450052, Zhengzhou, Henan, China
2
Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, 430079, Wuhan, Hubei, China
Received:
7
August
2023
Accepted:
12
September
2023
Published online:
20
October
2023
In this work, we investigate the semileptonic decays of meson to 
, 
and X(3872) within the framework of covariant light-front quark model (CLFQM). We combine the helicity amplitudes via the corresponding form factors to obtain the branching ratios of the semileptonic decays 
, 
and 
, with 
. In view of the 
anomaly released by the LHCb collaboration, it is necessary to systematically calculate the ratios 
with 
, which are helpful for checking the lepton flavor universality (LFU). We also take into account another two physical observables, the longitudinal polarization fraction 
and the forward–backward asymmetry 
, which can provide new clues for understanding the 
anomaly. Such theoretical predictions are necessary and interesting, and can be tested in future LHCb experiments.
© The Author(s) 2023
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Funded by SCOAP3. SCOAP3 supports the goals of the International Year of Basic Sciences for Sustainable Development.
