The Slac Polarized Electron Source and Beam for E-158 T. B. Humensky, for the E-158 Collaboration and the Slac Polarized Electron Source Group

SLAC E-158 is making the first measurement of parity violation in Møller scattering. E-158 measures the right-left cross-section asymmetry, ALR, in the scattering of a 45-GeV polarized electron beam off unpolarized electrons in a liquid hydrogen target. E-158 plans to measure the expected Standard Model asymmetry of ∼ 10 to an accuracy of better than 10. This paper discusses the performance of the SLAC polarized electron source and beam during E-158’s first physics run in April/May 2002. Contributed to International Workshop On From Parity Violation To Hadronic Structure And More ... Mainz, Germany June 5–June 8, 2002 ∗Work supported by Department of Energy contract DE–AC03–76SF00515. THE SLAC POLARIZED ELECTRON SOURCE AND BEAM FOR E-158 T. B. HUMENSKY, FOR THE E-158 COLLABORATION AND THE SLAC POLARIZED ELECTRON SOURCE GROUP Dept. of Physics, UVa E-mail: [email protected] SLAC E-158 is making the first measurement of parity violation in Møller scattering. E-158 measures the right-left cross-section asymmetry, ALR, in the scattering of a 45-GeV polarized electron beam off unpolarized electrons in a liquid hydrogen target. E-158 plans to measure the expected Standard Model asymmetry of ∼ 10 to an accuracy of better than 10. This paper discusses the performance of the SLAC polarized electron source and beam during E-158’s first physics run in April/May 2002.