Strange Quark Contributions to Nucleon Electric and Magnetic Form Factors from Parity-violating Electron Scattering Asymmetries in the Backward Angle G0 Experiment

Download or read book Strange Quark Contributions to Nucleon Electric and Magnetic Form Factors from Parity-violating Electron Scattering Asymmetries in the Backward Angle G0 Experiment written by Mathew O. Muether and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The G0 collaboration has measured parity-violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering at Q^2 = 0.22, 0.63 GeV^2. These asymmetries are sensitive to strange quark contributions to electric and magnetic properties of the nucleon, as well as to the axial current of the nucleon. The measurements were made using the polarized beam at Jefferson Laboratory by detecting electrons scattered at ~110 degrees from liquid targets. Together with previous results from the G0 forward angle measurement, the form factors which characterize the strange electric, strange magnetic and axial contributions were found to be G^{s}_{E}(0.221 GeV^2)= -0.0142305 +/- 0.035562 +/- 0.0181952 +/-0.0176497 G^{s}_{M}(0.221 GeV^2)=0.0833777 +/- 0.18337 +/- 0.0854892 +/- 0.0780912 G^{e}_{A}(0.221 GeV^2)=-0.501236 +/- 0.317127 +/- 0.193005 +/- 0.0878386 G^{s}_{E}(0.628 GeV^2)=0.110227 +/-0.0488068 +/- 0.0296044 +/- 0.0236998 G^{s}_{M}(0.628 GeV^2)=-0.12354 +/- 0.10953 +/- 0.0614285 +/- 0.0316972 G^{e}_{A}(0.628 GeV^2)=-0.197329 +/- 0.425414 +/- 0.256755 +/- 0.0948741 with statistical, point-to-point systematic and global systematic uncertainties given respectively. These results indicate small (