International Workshop on Physics with Positrons at Jefferson Lab (JPos17)

Session

Plenary 2

Sep 12, 2017, 8:40 AM

Room F113 (CEBAF Center)

Conveners

Plenary 2

• John Arrington (Argonne National Laboratory)

30. Measurement of TPE with electron/positron elastic scattering off the proton

Brian Raue (Florida International University)

9/12/17, 8:40 AM

Interference Physics

Oral Contribution

Since the discovery of the discrepancy between Rosenbluth and polarization-transfer measurements of the proton form-factor ratio $G_E/G_M$ there has been a renewed interest in measuring contributions to the elastic cross section from two-photon exchange (TPE). Three recent experiments conducted at CLAS, VEPP-3, and OLYMPUS directly determined the real part of the TPE amplitude by measuring the...

95. TPE Theory: Partonic Approach

Andrei Afanasev (GWU)

9/12/17, 9:15 AM

36. Overview of recent theoretical work on two-photon exchange

Peter Blunden (University of Manitoba)

9/12/17, 9:50 AM

Interference Physics

Oral Contribution

In this talk I will give an overview of recent progress in theoretical calculations of two-photon exchange (TPE) effects in elastic electron-proton scattering. This will include a survey of existing models and theoretical frameworks. TPE effects are relevant for extractions of proton form factors at high $Q^2$, and of the proton radius at low $Q^2$. Recent experiments to directly measure hard...