Next-to-leading order QCD corrections to Λ b → p form factors from light-cone sum rules

In this study, we compute the radiative corrections to the Λ b → p Λ b → p transition form factors at next-to-leading logarithmic accuracy. With the light-cone distribution amplitudes of the Λ b Λ b baryon, we employ the light-cone sum rules in the framework of soft-collinear effective theory, utilizing the method of regions to systematically extract the factorized contributions from different momentum regions . The factorization formulae of the vacuum-to- Λ b Λ b correlation function, constructed from the interpolating current for the energetic proton, are derived at leading power in mₚ / mΛ b m p / m Λ b . With our specific choice of interpolating current, only the twist-4 distribution amplitude of the Λ b Λ b baryon contributes to the form factors. Numerically, we find that the next-to-leading order QCD perturbative corrections reduce the tree-level form factors to approximately 65 $$%$$ % of their original value, with the next-to-leading-order jet function providing the dominant contribution. In the large-energy limit ( Eₚ → ∞ E p → ∞ ), the form factors exhibit a clear 1/Eₚ³ 1 / E p 3 scaling, consistent with the expected power-counting behavior. By applying the z -series parameterization to perform a combined fit of the form factors from our results and available lattice QCD simulations, we further investigate the decay rate of Λ b → p ⁻ ν ̄ Λ b → p ℓ - ν ¯ ℓ and extract the CKM matrix element |Vub| = (3.33± 0.43 ) × 10⁻³ | V ub | = ( 3.33 ± 0.43 ) × 10 - 3 .