Test of QCD through hadron form factors measurements at large momentum transfer

Abstract

We review the present situation with hadron form factors in space-like and time-like regions. The possibility to transfer high momenta, and therefore to access small internal nucleon distances, allows to test nucleon models in particular pQCD predictions such as quark counting rules and helicity conservation. We will focus here to the proton case, although general statements apply also to neutron and light hadrons.