Constraints on the Nucleon Strange Form Factors at Q^2 ~ 0.1 GeV^2

Autor: Aniol, K., Armstrong, D., Averett, T., Benaoum, H., Bertin, P.Y., Burtin, E., Cahoon, J., Cates, G., Chang, C., Chao, Y.-C., Chen, Jie, Choi, S., Chudakov, E., Craver, B., Cusanno, F., Decowski, P., Deepa, D., Ferdi, C., Feuerbach, R., Finn, J., Frullani, S., Fuoti, K., Garibaldi, F., Gilman, R., Glamazdin, O., Gorbenko, V., Grames, J., Hansknecht, J., Higinbotham, D., Holmes, R., Holmstrom, T., Humensky, T., Ibrahim, H., De Jager, C., Jiang, X., Kaufman, L., Kelleher, A., Kolarkar, A., Kowalski, S., Kumar, K., Lambert, D., Laviolette, P., LeRose, J., Lhuillier, D., Liyanage, N., Margaziotis, D., Mazouz, M., McCormick, K., Meekins, D., Meziani, Z.-E., Michaels, R., Moffit, B., Monaghan, P., Munoz-Camacho, C., Nanda, S., Nelyubin, V., Neyret, D., Paschke, K.D., Poelker, B., Pomatsalyuk, R., Qiang, Y., Reitz, B., Roche, J., Saha, A., Singh, J., Snyder, R., Souder, P.A., Stutzman, M., Subedi, R., Suleiman, R., Sulkosky, V., Tobias, W., Urciuoli, G., Vacheret, A., Voutier, E., Wang, K., Wilson, R., Wojtsekhowski, B., Zheng, X.
Přispěvatelé: Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), HAPPEX, Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2005
Předmět:
Zdroj: Physics Letters B
Physics Letters B, 2006, 635, pp.275-279. ⟨10.1016/j.physletb.2006.03.011⟩
Physics Letters B, Elsevier, 2006, 635, pp.275-279. ⟨10.1016/j.physletb.2006.03.011⟩
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2006.03.011⟩
Popis: We report the most precise measurement to date of a parity-violating asymmetry in elastic electron-proton scattering. The measurement was carried out with a beam energy of 3.03 GeV and a scattering angle =6 degrees, with the result A_PV = -1.14 +/- 0.24 (stat) +/- 0.06 (syst) parts per million. From this we extract, at Q^2 = 0.099 GeV^2, the strange form factor combination G_E^s + 0.080 G_M^s = 0.030 +/- 0.025 (stat) +/- 0.006 (syst) +/- 0.012 (FF) where the first two errors are experimental and the last error is due to the uncertainty in the neutron electromagnetic form factor. This result significantly improves current knowledge of G_E^s and G_M^s at Q^2 ~0.1 GeV^2. A consistent picture emerges when several measurements at about the same Q^2 value are combined: G_E^s is consistent with zero while G_M^s prefers positive values though G_E^s=G_M^s=0 is compatible with the data at 95% C.L.
Comment: minor wording changes for clarity, updated references, dropped one figure to improve focus
Databáze: OpenAIRE
Externí odkaz: