On BLM scale fixing in exclusive processes

I. V. Anikin, B. Pire, L. Szymanowski, O. V. Teryaev, S. Wallon

Published 2004-11-30, updated 2005-05-20Version 3

We discuss the BLM scale fixing procedure in exclusive electroproduction processes in the Bjorken regime. We show that in the case of vector meson production the usual way to aplly the BLM method fails due to singularities present in equations fixing the BLM scale. We argue that the BLM scale should be extracted from the squared amplitudes which are directly related to observables.