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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.

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