前向角弹性电子-质子散射中束流法向单自旋不对称的精确测量
核实验
2020-09-16 v2
摘要
由横向极化电子对非极化核子的散射产生的束流法向单自旋不对称，是与双光子交换过程的虚部相关的可观测量。我们报告了弹性电子-质子散射中束流法向单自旋不对称的 2% 精度测量，平均散射角 theta_lab = 7.9 度，平均能量 1.149 GeV。不对称结果为 B_n = -5.194 ± 0.067 (stat) ± 0.082 (syst) ppm。这是迄今为止该量最精确的测量，因此在远前向散射角（theta_lab → 0）处对双光子交换模型提供了严格检验，而在此角度下模型应最为可靠。
引用
@article{arxiv.2006.12435,
title = {Precision Measurement of the Beam-Normal Single-Spin Asymmetry in Forward-Angle Elastic Electron-Proton Scattering},
author = {QWeak collaboration and D. Androic and D. S. Armstrong and A. Asaturyan and K. Bartlett and J. Beaufait and R. S. Beminiwattha and J. Benesch and F. Benmokhtar and J. Birchall and R. D. Carlini and J. C. Cornejo and S. Covrig Dusa and M. M. Dalton and C. A. Davis and W. Deconinck and J. F. Dowd and J. A. Dunne and D. Dutta and W. S. Duvall and M. Elaasar and W. R. Falk and J. M. Finn and T. Forest and C. Gal and D. Gaskell and M. T. W. Gericke and J. Grames and V. M. Gray and K. Grimm and F. Guo and J. R. Hoskins and D. Jones and M. K. Jones and R. T. Jones and M. Kargiantoulakis and P. M. King and E. Korkmaz and S. Kowalski and J. Leacock and J. P. Leckey and A. R. Lee and J. H. Lee and L. Lee and S. MacEwan and D. Mack and J. A. Magee and R. Mahurin and J. Mammei and J. W. Martin and M. J. McHugh and D. Meekins and J. Mei and K. E. Mesick and R. Michaels and A. Micherdzinska and A. Mkrtchyan and H. Mkrtchyan and N. Morgan and A. Narayan and L. Z. Ndukum and V. Nelyubin and Nuruzzaman and W. T. H van Oers and V. F. Owen and S. A. Page and J. Pan and K. D. Paschke and S. K. Phillips and M. L. Pitt and R. W. Radloff and J. F. Rajotte and W. D. Ramsay and J. Roche and B. Sawatzky and T. Seva and M. H. Shabestari and R. Silwal and N. Simicevic and G. R. Smith and P. Solvignon and D. T. Spayde and A. Subedi and R. Subedi and R. Suleiman and V. Tadevosyan and W. A. Tobias and V. Tvaskis and B. Waidyawansa and P. Wang and S. P. Wells and S. A. Wood and S. Yang and P. Zang and S. Zhamkochyan},
journal= {arXiv preprint arXiv:2006.12435},
year = {2020}
}
备注
6 pages, 3 figures; Slightly revised version, after referee's comments; accepted in PRL