Vector mesons leading-twist longitudinal distribution amplitudes and related semi-leptonic decays within QCD sum rules
Abstract
In this work, we focus on the light vector meson leading-twist longitudinal distribution amplitudes (DAs) ϕ∥2;V(x,μ) with V = ρ, K∗, ϕ. A new scheme of QCD sum rule research with respect to DA suggested in 2021 by us is adopted. With an improved sum rule formula, the ξ-moments ⟨ξn⟩2;V∥ up to tenth order are calculated. In which, ⟨ξ2⟩∥2;ρ=0.225+0.013−0.012, ⟨ξ1⟩∥2;K∗=−0.0228+0.0042−0.0040, ⟨ξ2⟩∥2;K∗=0.217+0.007−0.007, ⟨ξ2⟩∥2;ϕ=0.209+0.020−0.020, and the corresponding Gegenbauer moments a2;∥2;ρ=0.074+0.039−0.036, a1;∥2;K∗=−0.038+0.007−0.007, a2;∥2;K∗=0.050+0.020−0.019, a2;∥2;ϕ=0.027+0.058−0.058 at the scale μ= 1 GeV, respectively. By fitting those ⟨ξn⟩∥2;V(n = 1,2,⋯,10) with the least squares method, the behaviors of leading-twist longitudinal DAs for ρ, K∗, ϕ are determined. In addition, we also analyze the impact of incorporating different numbers of ξ-moments into the fitting on the stability and reliability of the obtained DAs. Be different from the pion leading-twist DA, we find that the higher-order moments do not significantly change the reconstructed shapes of ϕ∥2;V(x,μ). Further, we recalculate the transition form factors and branching ratios of the D→(ρ,K∗), Ds→ϕ semi-leptonic decay processes.
Related
- Heavy-quark limit of B-meson distribution amplitudes in light-front holography with longitudinal confinement
- Two-loop QCD amplitudes for tt̅W production at the LHC in the leading-colour approximation
- Pion and η meson gravitational form factors from GPDs at non-zero skewness and distribution amplitudes within the Graviton Soft-Wall model
- Electromagnetic tails of B-meson light-cone distribution amplitudes
- Towards power corrections in the factorization of baryon quasi-distribution amplitudes in LaMET
BibTeX
@misc{luo2026vector,
title = {{Vector mesons leading-twist longitudinal distribution amplitudes and related semi-leptonic decays within QCD sum rules}},
author = {Wan-Bing Luo and Ru-Meng Pan and Ya-Xiong Wang and Tao Zhong},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2607.17496},
eprint = {2607.17496},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.17496},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Vector mesons leading-twist longitudinal distribution amplitudes and related semi-leptonic decays within QCD sum rules
AU - Wan-Bing Luo
AU - Ru-Meng Pan
AU - Ya-Xiong Wang
AU - Tao Zhong
PY - 2026
DA - 2026/10/21
PB - arXiv
DO - 10.48550/arxiv.2607.17496
UR - https://arxiv.org/abs/2607.17496
AB - In this work, we focus on the light vector meson leading-twist longitudinal distribution amplitudes (DAs) ϕ^∥_2;V(x,μ) with V = ρ, K^∗, ϕ. A new scheme of QCD sum rule research with respect to DA suggested in 2021 by us is adopted. With an improved sum rule formula, the ξ-moments ⟨ξ^n⟩_2;V^∥ up to tenth order are calculated. In which, ⟨ξ^2⟩^∥_2;ρ=0.225^+0.013_−0.012, ⟨ξ^1⟩^∥_2;K^∗=−0.0228^+0.0042_−0.0040, ⟨ξ^2⟩^∥_2;K^∗=0.217^+0.007_−0.007, ⟨ξ^2⟩^∥_2;ϕ=0.209^+0.020_−0.020, and the corresponding Gegenbauer moments a^2;∥_2;ρ=0.074^+0.039_−0.036, a^1;∥_2;K^∗=−0.038^+0.007_−0.007, a^2;∥_2;K^∗=0.050^+0.020_−0.019, a^2;∥_2;ϕ=0.027^+0.058_−0.058 at the scale μ= 1 GeV, respectively. By fitting those ⟨ξ^n⟩^∥_2;V(n = 1,2,⋯,10) with the least squares method, the behaviors of leading-twist longitudinal DAs for ρ, K^∗, ϕ are determined. In addition, we also analyze the impact of incorporating different numbers of ξ-moments into the fitting on the stability and reliability of the obtained DAs. Be different from the pion leading-twist DA, we find that the higher-order moments do not significantly change the reconstructed shapes of ϕ^∥_2;V(x,μ). Further, we recalculate the transition form factors and branching ratios of the D→(ρ,K^∗), D_s→ϕ semi-leptonic decay processes.
ER -