Eur. Phys. J. A 24, s2.115-s2.118 (2005)
DOI: 10.1140/epjad/s2005-04-026-x

Beam optics for electron scattering parity-violation experiments

Douglas H. Beck¹ and Mark L. Pitt<sup>2

1</sup>  Nuclear Physics Laboratory and Loomis Laboratory of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, IL 61801, USA
²  Department of Physics Virginia Polytechnic Institute and State University Blacksburg, VA 24061-0435, USA

(Received 15 November 2004 / Published online 08 February 2005)

Abstract

Parity-violating electron scattering experiments at intermediate energies measure asymmetries in the 10^-6-10^-5 range and therefore require stringent control of false asymmetries. One of the primary sources of such asymmetries is the combined effect of helicity-correlated changes in a certain beam property, accompanied by a change in the detector response. Careful control of the beam, including the optical properties of the acceleration and transport system, is required in order to reduce these false asymmetries to a manageable level. Developments in beam optics associated with the HAPPEX and G0 experiments at Jefferson Lab are presented.

PACS: 29.27.Hj Polarized beams - 13.60.-r Photon and charged-lepton interactions with hadrons - 25.30.-c Elastic electron scattering

© Società Italiana di Fisica, Springer-Verlag 2005