Radiative tail of the three-particle light-cone distribution amplitudes for the $\Lambda_b$ baryon in HQET

TL;DR

This paper calculates the radiative tail of three-particle light-cone distribution amplitudes for the mbda_b baryon within HQET, providing insights into their behavior at large distances and small momenta.

Contribution

It introduces a method to compute the radiative tail of mbda_b LCDAs in HQET and models their large-distance behavior, extending previous work on B-mesons.

Findings

Radiative tail affects mbda_b LCDAs similarly to B-mesons.

A simple extrapolation preserves analytic properties of LCDAs.

Qualitative behavior of LCDAs is consistent with known B-meson results.

Abstract

We calculate the so-called radiative tail for the three-particle light-cone distribution amplitudes (LCDAs) of the $\Lambda_b$ baryon, following from the short-distance expansion of the defining light-ray operators in heavy-quark effective theory (HQET). To illustrate the effect of the radiative tail, we introduce a simple (model-dependent) extrapolation to large distances (respectively small momenta), which preserves the analytic properties of the LCDAs in HQET. We observe a similar qualitative behaviour as has been discussed for the $B$-meson case.