Measuring Two-Photon Exchange Contributions to the e-n Elastic Scattering Cross-section on the SBS at JLab

ORAL

Abstract

The nTPE experiment ran as part of the first segment of JLab's Super BigBite Spectrometer (SBS) program. nTPE is a measurement of the two-photon exchange contribution to the electron-neutron elastic scattering cross section at a four-momentum transfer of Q2 = 4.5 (GeV/c)2. Comparisons of nucleon form factor measurements acquired through polarization transfer and the Rosenbluth technique show discrepancies as the four-momentum transfer, Q2, increases. Two photon exchange is strongly favored as the reason for this discrepancy and this experiment assesses the contribution of two-photon exchange in e-N elastic scattering processes by elastically scattering electrons off neutrons in a deuterium target. Large-scale calibrations have completed and physics analysis to extract GMn at each kinematic for nTPE assessment is nearing completion. This talk will discuss the nTPE experiment and associated analysis milestones.

*Department of Energy: DE-FG02-03ER41240

Presenters

  • John A Boyd

    • University of Virginia

Authors

  • John A Boyd

    • University of Virginia
  • Nilanga Liyanage

    • University of Virginia
    • Univ of Virginia
  • Sheren A Alsalmi

    • King Saud Univ
  • Eric Fuchey

    • Mississippi State University
  • Bogdan Wojtsekhowski

    • Jefferson Lab/Jefferson Science Associat
    • University of Virginia