Status of SAMPLE Parity Violation Experiments

M.L. Pitt

Virginia Polytechnic Institute and State University
for the SAMPLE Collaboration

The SAMPLE experiment performs low Q2 parity-violating elastic and quasielastic electron scattering on proton and deuteron targets at backward angles. The experiment is performed at the MIT-Bates Linear Accelerator Center. From these measurements, we extract a value for the nucleon's strange magnetic form factor and the axial e-N form factor. I will report on the results and implications of the measurements completed at Q2 = 0.1 GeV2 (refs. 1-3). I will also report on the status of a measurement on deuterium at Q2 = 0.04 GeV2 (ref. 4) scheduled to run this fall at MIT-Bates.

References:

  1. SAMPLE Experiment - parity violation results
    1. B. A. Mueller et al., Phys. Rev. Lett. 78, 3824 (1997). (LANL preprint)
    2. D.T. Spayde et al., Phys. Rev. Lett. 84, 1106 (2000). (LANL preprint)
    3. R. Hasty et al., Science 290, 2117 (2000). (LANL preprint)
    4. MIT-Bates Experiment 00-04, T. Ito, spokesperson
  2. e-p Vector Analyzing Power measured by SAMPLE
    1. S.P. Wells et al., Phys. Rev. C63, 064001 (2001) (LANL preprint)
  3. Theory of strange magnetic form factor
    1. D.Beck and B.R. Holstein, Int. J. Mod. Phys. E10,1 (2001) - review article with list of theory references (LANL preprint)
  4. Theory of e-N axial form factor and nucleon's anapole moment
    1. M.J. Musolf and B.R. Holstein, Phys. Lett. B242, 461 (1990).
    2. M.J. Musolf and B.R. Holstein, Phys. Rev. D43, 2956 (1991).
    3. S-L. Zhu, S.J. Puglia, B.R. Holstein, M.J. Ramsey-Musolf, Phys. Rev. D62 033008 (2000). (LANL preprint)
    4. C.M. Maekawa and U. van Kolck, Phys. Lett. B478, 73 (2000). (LANL preprint)
    5. C.M. Maekawa, J.S. Veiga, U. van Kolck, Phys. Lett. B488, 167 (2000). (LANL preprint)
    6. D. Riska, Nucl. Phys. A678, 79 (2000). (LANL preprint)