Ξc → Ξ Semileptonic Decays: An LCSR View on the Experiment-Lattice Tension

We present a light-cone QCD sum rule analysis of the semileptonic decays of Ξc baryons, focusing on the channels Ξc⁰ → Ξ⁻ ⁺ ν_, and Ξc⁺ → Ξ⁰ ⁺ ν_. The transition form factors are calculated within the light-cone QCD sum rules framework, using the distribution amplitudes of the heavy Ξc baryons. The obtained form factors are then used to compute the differential and total decay widths, as well as the branching fractions. Our numerical results for the branching fractions are B(Ξc⁰ → Ξ⁻ ⁺ ν₎ = (3.73 ± 1.04)~% , B(Ξc⁰ → Ξ⁻ μ⁺ ν_μ) = (3.59 ± 1.01)~%, B(Ξc⁺ → Ξ⁰ ⁺ ν₎ = (11.2 ± 3.25)~%, and B(Ξc⁺ → Ξ⁰ μ⁺ ν_μ) = (10.8 ± 3.13)~%. These results are in good agreement with recent lattice QCD calculations, while being larger than the current experimental measurements and differing from the predictions of other theoretical approaches.