用μp弹性散射研究质子“半径”之谜
Studying the Proton "Radius" Puzzle with μp Elastic Scattering
摘要：
质子半径之谜是由μ介子氢确定的质子半径与由原子氢能级跃迁和弹性散射确定的质子半径之间的不一致。目前还没有普遍接受的解决方案，可能的解决方案通常分为三类：两个半径不同是由于新的超标准模型物理，两个半径不同是由于核子结构的新方面，以及两个半径相同，但在ep实验中存在被低估的不确定性或其他问题。保罗·谢勒研究所的μ介子质子散射实验（MUSE）是对μ^+ p和e^+ p弹性散射以及μ^- p和e^- p弹性散射的同时测量，这将允许确定μp和ep相互作用的一致性。+和-电荷散射之间的差异是敏感的双光子交换效应，高阶修正的散射过程。当Q^2 -> 0时，截面的斜率决定了质子的“半径”。我们计划测量相对截面在百分之零点几的典型水平，这应该允许质子半径被确定在约0.01 fm的水平，类似于以前的ep测量。测量将测试质子半径之谜的几种可能的解释，包括一些超越标准模型物理学的模型，一些新的强子物理学模型，以及从散射数据中提取半径的一些问题。
英文摘要：
The Proton Radius Puzzle is the inconsistency between the proton radius determined from muonic hydrogen and the proton radius determined from atomic hydrogen level transitions and ep elastic scattering. No generally accepted resolution to the Puzzle has been found. Possible solutions generally fall into one of three categories: the two radii are different due to novel beyond-standard-model physics, the two radii are different due to novel aspects of nucleon structure, and the two radii are the same, but there are underestimated uncertainties or other issues in the ep experiments. The MUon proton Scattering Experiment (MUSE) at the Paul Scherrer Institut is a simultaneous measurement of μ^+ p and e^+ p elastic scattering, as well as μ^- p and e^- p elastic scattering, which will allow a determination of the consistency of the μp and the ep interactions. The differences between + and - charge scattering are sensitive to two-photon exchange effects, higher-order corrections to the scattering process. The slopes of the cross sections as Q^2 -> 0 determine the proton "radius". We plan to measure relative cross sections at a typical level of a few tenths of a percent, which should allow the proton radius to be determined at the level of ~0.01 fm, similar to previous ep measurements. The measurements will test several possible explanations of the proton radius puzzle, including some models of beyond-standard-model physics, some models of novel hadronic physics, and some issues in the radius extraction from scattering data.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
