Polarization transfer in the 2H(e⃗,e′p⃗)n reaction up to Q2=1.61 (GeV/c)2

Phys. Rev. C 06/2006; 73(6). DOI: 10.1103/PhysRevC.73.064004
Source: arXiv

ABSTRACT The recoil proton polarization was measured in the 2H(e⃗,e′p⃗)n reaction in Hall A of the Thomas Jefferson National Accelerator Facility. The electron kinematics were centered on the quasielastic peak (xBj≈1) and included three values of the squared four-momentum transfer, Q2=0.43,1.00 and 1.61 (GeV/c)2. For Q2=0.43 and 1.61 (GeV/c)2, the missing momentum, pm, was centered at zero, whereas for Q2=1.00 (GeV/c)2 two values of pm were chosen: 0 and 174 MeV/c. At low pm, the Q2 dependence of the longitudinal polarization, Pz′, is not well described by a state-of-the-art calculation. Further, at higher pm, a 3.5σ discrepancy was observed in the transverse polarization, Px′. Understanding the origin of these discrepancies is important to confidently extract the neutron electric form factor from the analogous 2H(e⃗,e′n⃗)p experiment.

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Available from: Sabine Jeschonnek, Dec 27, 2013
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