Aniol K A, Armstrong D S, Averett T, Benaoum H, Bertin P Y, Burtin E, Cahoon J, Cates G D, Chang C C, Chao Y-C, Chen J-P, Choi Seonho, Chudakov E, Craver B, Cusanno F, Decowski P, Deepa D, Ferdi C, Feuerbach R J, Finn J M, Frullani S, Fuoti K, Garibaldi F, Gilman R, Glamazdin A, Gorbenko V, Grames J M, Hansknecht J, Higinbotham D W, Holmes R, Holmstrom T, Humensky T B, Ibrahim H, de Jager C W, Jiang X, Kaufman L J, Kelleher A, Kolarkar A, Kowalski S, Kumar K S, Lambert D, LaViolette P, LeRose J, Lhuillier D, Liyanage N, Margaziotis D J, Mazouz M, McCormick K, Meekins D G, Meziani Z-E, Michaels R, Moffit B, Monaghan P, Munoz-Camacho C, Nanda S, Nelyubin V, Neyret D, Paschke K D, Poelker M, Pomatsalyuk R, Qiang Y, Reitz B, Roche J, Saha A, Singh J, Snyder R, Souder P A, Subedi R, Suleiman R, Sulkosky V, Tobias W A, Urciuoli G M, Vacheret A, Voutier E, Wang K, Wilson R, Wojtsekhowski B, Zheng X
California State University, Los Angeles, Los Angeles, California 90032, USA.
Phys Rev Lett. 2006 Jan 20;96(2):022003. doi: 10.1103/PhysRevLett.96.022003. Epub 2006 Jan 18.
We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle <theta(lab)> = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero.
我们测量了极化电子与4He弹性散射过程中的宇称破坏电弱不对称性,平均散射角<θ(lab)> = 5.7度,四动量转移Q2 = 0.091 GeV2。首次从这些数据中分离出核子的奇异电形状因子G(E)s。测量得到的不对称性A(PV) = (6.72 +/- 0.84(统计) +/- 0.21(系统) x 10^(-6),得出G(E)s = -0.038 +/- 0.042(统计) +/- 0.010(系统),与零相符。