2023/08/27 by Tao Zhong, Zhong, Tao, Ya-Hong Dai +3 · 1 citation
Physics and Astronomy · #FOS: Physical sciences #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.2308.14032
openalex publication_date 2023/08/27 · openalex created_date 2023/08/31 · openalex updated_date 2026/07/28
Motivated by our previous work [Phys. Rev. D 104, no.1, 016021 (2021)] on pionic leading-twist distribution amplitude (DA), we revisit ρ-meson leading-twist longitudinal DA ϕ2;ρ^‖(x,μ) in this paper. A model proposed by Chang based on the Dyson-Schwinger equations (DSEs) is adopted to describe the behavior of ϕ2;ρ^‖(x,μ). On the other hand, the ξ-moments of ϕ2;ρ^‖(x,μ) are calculated with the QCD sum rules in the framework of the background field theory. The sum rule formula for those moments are improved. More accurate values for the first five nonzero ξ-moments at typical scale μ=1, 1.4, 2, 3~\rm GeV are given, e.g., at μ= 1~\rm GeV, \modi⟨ξ2⟩2;ρ^‖ = 0.220(6) , ⟨ξ4⟩2;ρ^‖ = 0.103(4), ⟨ξ6⟩2;ρ^‖ = 0.066(5), ⟨ξ8⟩2;ρ^‖ = 0.046(4) and ⟨ξ10⟩2;ρ^‖ = 0.035(3). By fitting those values with the least squares method, the DSE model for ϕ2;ρ^‖(x,μ) is determined. By taking the left-handed current light-cone sum rule approach, we get the transition form factor at large recoil region, \it i.e. A1(0) = 0.498+0.014-0.012, A2(0)=0.460+0.055-0.047, V(0) = 0.800+0.015-0.014, and the ratio r2 = 0.923+0.133-0.119, rV = 1.607+0.071-0.071. After making the extrapolation with a rapidly converging series based on z(t)-expansion, we present the decay width for the semileptonic decays D→ρℓ+ν_ℓ. Finally, the branching fractions are B(D0→ ρ- e+ νe) = 1.889+0.176-0.170± 0.005, B(D+ → ρ0 e+ νe) = 2.380+0.221-0.214± 0.012, B(D0→ ρ- μ+ νμ) = 1.881+0.174-0.168± 0.005, B(D+ → ρ0 μ+ νμ) =2.369+0.219-0.211± 0.011.