Measurement of Strange Quark Contributions to the Vector Form Factors of the Proton at Q[superscript 2]=0.22 (GeV/c)[superscript 2]

• Main Authors: Baunack, S. (Author), Aulenbacher, K. (Author), Balaguer Rios, D. (Author), Capozza, L. (Author), Diefenbach, J. (Author), Glaser, B. (Author), von Harrach, D. (Author), Imai, Y. (Author), KabuB, E.-M (Author), Kothe, R. (Author), Lee, J. H. (Author), Merkel, H. (Author), Mora Espi, M. C. (Author), Muller, U. (Author), Shilling, E. (Author), Stephan, G. (Author), Weinrich, C. (Author), Arvieux, J. (Author), El-Yakoubi, M. A. (Author), Frascaria, R. (Author), Kunne, R. (Author), Maas, F. E. (Author), Morlet, M. (Author), Ong, S. (Author), van de Wiele, J. (Author), Kowalski, Stanley B. (Contributor), Prok, Yelena (Contributor), Taylor, S. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2010-03-17T17:32:27Z.
• Subjects: Article
• Online Access: Get fulltext

 A new measurement of the parity violating asymmetry in elastic electron scattering on hydrogen at backward angles and at a four momentum transfer of Q[superscript 2]=0.22   (GeV/c)[superscript 2] is reported here. The measured asymmetry is A[subscript LR]=(-17.23±0.82stat±0.89syst)×10-6. The standard model prediction assuming no strangeness is A[subscript 0]=(-15.87±1.22)×10[superscript -6]. In combination with previous results from measurements at forward angles, it is possible to disentangle for the first time the strange form factors at this momentum transfer, GE[superscript s]=0.050±0.038±0.019 and GM[superscript s]=-0.14±0.11±0.11.