Lawrence Berkeley National Laboratory

The proton electric and magnetic form factors, GE and GM, are intrinsically connected to the spatial distribution of charge and magnetization in the proton. For decades, Rosenbluth separation measurements of the angular dependence of elastic e--p scattering were used to extract GE and GM. More recently, polarized electron scattering measurements, aiming to improve the precision of GE extractions, showed significant disagreement with Rosenbluth measurements at large momentum transfers (Q2). This discrepancy is generally attributed to neglected two-photon exchange (TPE) corrections. At larger Q2 values, a new ‘Super-Rosenbluth’ technique was used to improve the precision of the Rosenbluth extraction, allowing for a better quantification of the discrepancy, while comparisons of e+-p and e--p scattering indicated the presence of TPE corrections, but at Q2 values below where a clear discrepancy is observed. In this work, we demonstrate the significant benefits to combining the Super-Rosenbluth technique with positron beam measurements. This approach provides a greater kinematic reach and is insensitive to some of the key systematic uncertainties in previous positron measurements.