Strange-quark contributions to parity-violating asymmetries in the forward g0 electron-proton scattering experiment.

/ Authors

D. Armstrong, J. Arvieux, R. Asaturyan, T. Averett, S. Bailey, G. Batigne, D. Beck, E. Beise, J. Benesch, L. Bimbot

and 103 more authors

J. Birchall, A. Biselli, P. Bosted, E. Boukobza, H. Breuer, R. Carlini, R. Carr, N. Chant, Y. Chao, S. Chattopadhyay, R. Clark, S. Covrig, A. Cowley, D. Dale, C. Davis, W. Falk, J. Finn, T. Forest, G. Franklin, C. Furget, D. Gaskell, J. Grames, K. Griffioen, K. Grimm, B. Guillon, H. Guler, L. Hannelius, R. Hasty, A. Allen, T. Horn, K. Johnston, M. Jones, P. Kammel, R. Kazimi, P. King, P. King, A. Kolarkar, E. Korkmaz, W. Korsch, S. Kox, J. Kuhn, J. Lachniet, L. Lee, J. Lenoble, E. Liatard, Jianglai Liu, B. Loupias, A. Lung, G. MacLachlan, D. Marchand, J. W. Martin, J. W. Martin, K. Mcfarlane, D. McKee, R. Mckeown, F. Merchez, H. Mkrtchyan, B. Moffit, M. Morlet, I. Nakagawa, K. Nakahara, M. Nakos, R. Neveling, S. Niccolai, S. Ong, S. Page, V. Papavassiliou, S. Pate, S. Phillips, M. Pitt, M. Poelker, T. Porcelli, T. Porcelli, G. Quéméner, B. Quinn, W. Ramsay, A. Rauf, J. Réal, J. Roche, J. Roche, P. Roos, G. Rutledge, J. Secrest, N. Simicevic, G. Smith, D. Spayde, D. Spayde, S. Stepanyan, M. Stutzman, V. Sulkosky, V. Tadevosyan, R. Tieulent, J. Wiele, W. Oers, E. Voutier, W. Vulcan, G. Warren, S. Wells, S. Williamson, S. Wood, C. Yan, J. Yun, V. Zeps

/ Abstract

We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments.

Journal: Physical review letters

DOI: 10.1103/PhysRevLett.95.092001