JLab Hall-A Magnetic Form Factor of the Neutron (GnM) Experiment Analysis Update

ORAL

Abstract

The Measurement of the Magnetic Form Factor of the Neutron (GnM) experiment (E12-09-019) took place from October 2021 through February 2022 in Hall-A at Jefferson Lab. The ``ratio method" was used in this experiment, which involved detecting both neutron-tagged d(e,e'n) and proton-tagged d(e,e'p) quasi-elastic electron scattering off a deuteron target. The experiment explored five kinematic points ranging from 3.5 GeV2/c2 to 13.5 GeV2/c2, with beam energies reaching up to 9.91 GeV. This measurement is part of the Super Bigbite Spectrometer (SBS) project, which is an ongoing experiment series in Hall-A at Jefferson Lab. The primary goals of the SBS program is to measure nucleon form factors with unprecedentedly high Q2 and high precision. The ratio method for extracting GnM benefits from significantly reduced systematic uncertainties, as many of them cancel out when taking the cross-section ratio of d(e,e'n) and d(e,e'p) reactions. However, some uncertainties, such as neutron and proton detection efficiencies, inelastic background contribution, nuclear corrections, radiative corrections, and neutron and proton misidentification, still need to be studied and quantified. This talk will provide an introduction to the SBS nucleon form factor program and the GnM experiment, followed by an account of the progress made in the analysis of the GnM experiment.

Presenters

  • Anuruddha D Rathnayake

    University of Virginia

Authors

  • Anuruddha D Rathnayake

    University of Virginia

  • David Hamilton

    University of Glascow, University of Glasgow

  • Alexandre Camsonne

    Jefferson Lab/Jefferson Science Associates

  • Brian Quinn

    Carnegie Mellon Univ

  • Bogdan Wojtsekhowski

    Jefferson Lab/Jefferson Science Associat, University of Virginia

  • Nilanga Liyanage

    University of Virginia, Univ of Virginia