Large $p_{\perp}$ Exclusive Processes:RECENT Developments

P. Kroll

Published 1993-11-02Version 1

Recent improvements of the hard scattering picture for exclusive reactions, namely the inclusion of both Sudakov corrections and the intrinsic transverse momentum dependence of the hadronic wave function, are reviewed. On account of these improvements the perturbative contribution to the pion's form factor can be calculated in a theoretically self-consistent way for momentum transfers as low about $2\,{\rm GeV}$. This is achieved at the expense of a substantial suppression of the perturbative contribution in the few GeV region. Eventual higher twist contributions are also discussed.\\