6533b856fe1ef96bd12b30f8

RESEARCH PRODUCT

How to reconcile the Rosenbluth and the polarization transfer method in the measurement of the proton form factors

Pierre A.m. GuichonMarc Vanderhaeghen

subject

Condensed Matter::Soft Condensed MatterPhysicsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Physics::Plasma PhysicsQuantum electrodynamicsFOS: Physical sciencesGeneral Physics and AstronomyAtomic physicsPolarization (waves)Nuclear Experiment

description

The apparent discrepancy between the Rosenbluth and the polarization transfer method for the ratio of the electric to magnetic proton form factors can be explained by a two-photon exchange correction which does not destroy the linearity of the Rosenbluth plot. Though intrinsically small, of the order of a few percent of the cross section, this correction is kinematically enhanced in the Rosenbluth method while it is small for the polarization transfer method, at least in the range of (Q^2) where it has been used until now.

10.1103/physrevlett.91.142303http://arxiv.org/abs/hep-ph/0306007