Renormalon model of twist-4 corrections to the pion distribution amplitude

In this paper we describe a renormalon-inspired model of twist-4 power corrections to the light-cone pion distribution amplitude, and compare it to the results obtained using the conformal wave expansion. We find that the overall functional form predicted in this renormalon model is similar to the one predicted in the standard approach to higher twist contributions involving an expansion in conformal operators. However, small discrepancies at the end-points allow for a discussion on the convergence properties of the conformal expansion. (C) 2000 Elsevier Science B.V. All lights reserved.