Measurement of the neutral weak form factors of the proton

Aniol, KA Armstrong, DS Baylac, M Burtin, E Calarco, J Cates, GD Cavata, C Chen, JP Chudakov, E Dale, D de Jager, CW Deur, A Djawotho, P Epstein, MB Escoffier, S Ewell, L Falletto, N Finn, JM Fissum, K Fleck, A Frois, B Gao, J Garibaldi, F Gasparian, A Gerstner, GM Gilman, R Glamazdin, A Gomez, J Gorbenko, V Hansen, O Hersman, F Holmes, R Holtrop, M Humensky, B Incerti, S Jardillier, J Jones, MK Jorda, J Jutier, C Kahl, W Kim, DH Kim, MS Kramer, K Kumar, KS Kuss, M LeRose, J Leuschner, M Lhuillier, D Liyanage, N Lourie, R Madey, R Margaziotis, DJ Marie, F Martino, J Mastromarino, P McCormick, K McIntyre, J Meziani, ZE Michaels, R Miller, GW Neyret, D Perdrisat, C Petratos, GG Pomatsalyuk, R Price, JS Prout, D Punjabi, V Pussieux, T Quemener, G Rutledge, G Rutt, PM Saha, A Souder, PA Spradlin, M Suleiman, R Thompson, J Todor, L Ulmer, PE Vlahovic, B Wijesooriya, K Wilson, R Wojtsekhowski, B

Ka. Aniol et al., Measurement of the neutral weak form factors of the proton, PHYS REV L, 82(6), 1999, pp. 1096-1100

18

INGLESE

Article

Physics

PHYSICAL REVIEW LETTERS

0031-9007 → ACNP

82

6

1999

1096 - 1100

ISI

0031-9007(19990208)82:6<1096:MOTNWF>2.0.ZU;2-Z

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The kinematic point [[th eta(1ab)] = 12.3 degrees and [Q(2)] = 0.48 (GeV/c)(2)] is chosen to provide sensitivity, at a level that is of theoretical interest, to the strange el ectric form factor G(E)(s). The result, A = -14.5 +/- 2.2 ppm, is consisten t with the electroweak standard model and no additional contributions from strange quarks. In particular, the measurement implies G(E)(s) + 0.39G(M)(s ) = 0.023 +/- 0.034(stat) +/- 0.022(syst) +/- 0.026(delta G(E)(n)), where t he last uncertainty arises from the estimated uncertainty in the neutron el ectric form factor. [S0031-9007(98)08312-4].