RT Journal Article
T1 Local two-photon couplings and the J=0 fixed pole in real and virtual Compton scattering
A1 Llanes Estrada, Felipe José
A1 Brodsky, Stanley J
A1 Szczepaniak, Adam P
AB The local coupling of two photons to the fundamental quark currents of a hadron gives an energy-independent contribution to the Compton amplitude proportional to the charge squared of the struck quark, a contribution which has no analog in hadron scattering reactions. We show that this local contribution has a real phase and is universal, giving the same contribution for real or virtual Compton scattering for any photon virtuality and skewness at fixed momentum transfer squared t. The t dependence of this J=0 fixed Regge pole is parameterized by a yet unmeasured even charge conjugation form factor of the target nucleon. The t=0 limit gives an important constraint on the dependence of the nucleon mass on the quark mass through the Weisberger relation. We discuss how this 1/x form factor can be extracted from high-energy deeply virtual Compton scattering and examine predictions given by models of the H generalized parton distribution.
PB Americal Physical Society
SN 1550-7998
YR 2009
FD 2009-02
LK https://hdl.handle.net/20.500.14352/43970
UL https://hdl.handle.net/20.500.14352/43970
LA eng
NO © 2009 The American Physical Society.
DS Docta Complutense
RD 7 abr 2025