A measurement of the absolute neutron beam polarization produced by an optically-pumped 3He spin filter

D. R. Rich; J. D. Bowman; B. E. Crawford; P. P. J. Delheij; M. A. Espy; T. Haseyama; G. Jones; C. D. Keith; J. Knudson; M. B. Leuschner; A. Masaike; Y. Masuda; Y. Matsuda; S. I. Penttila; V. R. Pomeroy; D. A. Smith; W. M. Snow; S. L. Stephenson; A. K. Thompson; V. Yuan

arXiv · physics/9908050

A measurement of the absolute neutron beam polarization produced by an optically-pumped 3He spin filter

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Abstract

The capability of performing accurate measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically-pumped polarized 3He spin filter and a relative transmission measurement technique. 3He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

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D. R. Rich, J. D. Bowman, B. E. Crawford, P. P. J. Delheij, M. A. Espy, T. Haseyama, G. Jones, C. D. Keith, J. Knudson, M. B. Leuschner, A. Masaike, Y. Masuda, Y. Matsuda, S. I. Penttila, V. R. Pomeroy, D. A. Smith, W. M. Snow, S. L. Stephenson, A. K. Thompson, V. Yuan. 1999-08-25. A measurement of the absolute neutron beam polarization produced by an optically-pumped 3He spin filter. https://arxiv.org/abs/physics/9908050

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