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The Scattering of Polarized Electrons from Polarized 3He: First Experiments and Implications for the Measurement of GEn

  • A. M. Bernstein
Part of the Few-Body Systems book series (FEWBODY, volume 6)

Abstract

The fact that the neutron is not an elementary particle was discovered long ago when the magnetic moment was measured and found not to be equal to the Dirac value of zero. Subsequent quasi-elastic electron deuteron scattering data showed that the neutron magnetic form factor was not point like.1 This internal structure can be explained as due to the presence of (at least) up and down quarks. If the up and down quark wave functions have the same radial dependence the charge form factor of the neutron G E n (q2) = 0; if they are not equal then G E n ≠ 0. We do not have much accurate data for G E n , but the measurement of the charge RMS radius from thermal neutron electron scattering2 demonstrates that the up and down quark wave functions are not equal. This has been explained by the tensor part of the color hyperfine interaction3,4 causing the up and down quark wave functions to differ.4,5 A measurement of G E n (q2) would provide a test of nucleon models.6

Keywords

Form Factor Final State Interaction Target Polarization Charge Form Factor Kinematic Regime 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • A. M. Bernstein
    • 1
  1. 1.Physics Department and Laboratory for Nuclear ScienceMassachusetts Institute of TechnologyCambridgeUSA

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