Scaling and the asymptotic behaviour of form factors

Abstract

It is shown that if all spin averaged matrix elements for the production of an arbitrary hadronic state |i> by the absorption of a virtual photon of momentum q on a proton vanish as q²→∞ (space-like), and if this asymptotic behaviour satisfies a certain smoothness condition when m_i² also becomes large, then Bjorken scaling requires the vanishing to be faster than any power of q². Commonly accepted analyticity properties of the relevant amplitudes are assumed.