First Results from Sld with Polarized Electron the Sld Collaboration
نویسنده
چکیده
The SLAC Linear Collider (SLC) has been modified to collide a longitudinally polarized electron beam with the unpolarized positron beam. We review the beginning of polarized beam running at the SLC, and report on the measurement of the left-right cross section asymmetry (ALR) made with a sample of 10,224 Z decays collected over the course of the 1992 run. The average beam polarization for this set of Z decays was 22.4 + 0.6%( syst.). ALR was measured to be 0.100 f 0.044 (stat. )*0.004 (syst.). From this me~urement, the weak mixing angle defined at the Z boson pole is determined to be sin2 O% = 0.2378 A0.0056~0.0005. i *Work supported by the Department of Energy, contract DE-AC03-76SFO0515.
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