Two-variable longitudinal distribution of the Λb in a three-quark light-front model
Abstract
We determine a normalized two-variable longitudinal distribution of the Λb=(ud)b baryon from a covariant three-quark light-front wave function. The scalar ud channel is selected with the good-component structure Cγ5γ+, and the two independent transverse momenta are integrated without introducing an elementary diquark. The resulting model-scale valence distribution, Ψ2LF(xu,xd), retains both the heavy--light and internal-light momentum scales of the parent wave function. It is symmetric under xu↔ xd, is concentrated where both light-quark fractions are small, and separates the total light-pair momentum from its internal sharing. For the central parameter set we find ⟨ xu⟩=⟨ xd⟩=0.130, ⟨ xb⟩=0.739, ⟨ζ2⟩=0.153, and ⟨ζ4⟩=0.055, where ζ=(xu−xd)/(xu+xd). Parameter variations give ⟨ xu⟩=0.130+0.007−0.007, ⟨ xb⟩=0.739+0.014−0.014, ⟨ζ2⟩=0.153+0.014−0.016, and ⟨ζ4⟩=0.055+0.009−0.009. The heavy--light momentum partition is controlled mainly by βb,ud and mb, whereas the internal u--d sharing is most sensitive to βud. The result provides a compact finite-mass benchmark for three-quark longitudinal structure, with distinct observables for heavy--light momentum sharing and correlations inside the light pair.
Related
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BibTeX
@misc{xu2026twovariable,
title = {{Two-variable longitudinal distribution of the $Λ_b$ in a three-quark light-front model}},
author = {Shuai Xu and Xiao-Nan Li},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.21148},
eprint = {2610.21148},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.21148},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Two-variable longitudinal distribution of the Λ_b in a three-quark light-front model
AU - Shuai Xu
AU - Xiao-Nan Li
PY - 2026
DA - 2026/10/15
PB - arXiv
DO - 10.48550/arxiv.2610.21148
UR - https://arxiv.org/abs/2610.21148
AB - We determine a normalized two-variable longitudinal distribution of the Λ_b=(ud)b baryon from a covariant three-quark light-front wave function. The scalar ud channel is selected with the good-component structure Cγ_5γ^+, and the two independent transverse momenta are integrated without introducing an elementary diquark. The resulting model-scale valence distribution, Ψ_2^LF(x_u,x_d), retains both the heavy--light and internal-light momentum scales of the parent wave function. It is symmetric under x_u↔ x_d, is concentrated where both light-quark fractions are small, and separates the total light-pair momentum from its internal sharing. For the central parameter set we find ⟨ x_u⟩=⟨ x_d⟩=0.130, ⟨ x_b⟩=0.739, ⟨ζ^2⟩=0.153, and ⟨ζ^4⟩=0.055, where ζ=(x_u−x_d)/(x_u+x_d). Parameter variations give ⟨ x_u⟩=0.130^+0.007_−0.007, ⟨ x_b⟩=0.739^+0.014_−0.014, ⟨ζ^2⟩=0.153^+0.014_−0.016, and ⟨ζ^4⟩=0.055^+0.009_−0.009. The heavy--light momentum partition is controlled mainly by β_b,ud and m_b, whereas the internal u--d sharing is most sensitive to β_ud. The result provides a compact finite-mass benchmark for three-quark longitudinal structure, with distinct observables for heavy--light momentum sharing and correlations inside the light pair.
ER -