2025/10/14 by W. Zhang, Zhang, Wen-Jing, Liu, Xin
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2510.12216
openalex publication_date 2025/10/14 · openalex created_date 2025/10/17 · openalex updated_date 2026/07/29
We perform an improved perturbative QCD study of the decays Bc+ → ηc L+,where L denotes the light ground-state pseudoscalar, vector mesons and the corresponding p-wave scalar, axial-vector, and tensor ones, and predict their branching ratios (BRs) associated with relative ratios at leading order in the strong coupling αs. Our results \rm BR(Bc+ → ηc π+) =(2.03+0.53-0.41) × 10-3 and \rm BR(Bc+ → ηc π+)/\rm BR(Bc+ → J/ψπ+) = 1.74+0.66-0.50 are consistent with several available predictions in different approaches within uncertainties. Inputting the measured ηc → p p and ηc → π+π- (π+π-, K+ K-, p p) BRs with p here being a proton, we derive the multibody Bc+ → ηc (π, ρ)+ BRs through secondary decay chains via resonance ηc under the narrow-width approximation, which might facilitate the (near-)future tests of Bc → ηc decays. Under the q q assignment for light scalars, different to Bc decaying into J/ψ plus a scalar meson and other Bc+ → ηc L+ modes, surprisingly small ΔS =0 BRs around \cal O(10-7-10-9) and highly large ratios near \cal O(102) between the ΔS=1 and ΔS=0 BRs are found in the Bc decays to ηc plus light scalars, with S being strange number. Many large BRs and interesting ratios presented in this work could be tested by the Large Hadron Collider experiments, which would help us to examine the reliability of this improved perturbative QCD formalism for Bc-meson decays and further understand the QCD dynamics in the considered decay modes, as well as in the related hadrons.