Laser spectroscopy of muonic atoms has been recently used to probe properties of light nuclei with unprecedented precision. We introduce nuclear effects in hydrogen-like atoms, nucleon structure quantities (form factors, structure functions, polarizabilities), and their effects in the Lamb shift and hyperfine splitting (HFS) of muonic hydrogen (μH). Updated theory predictions for the Lamb shift and HFS in μH are presented. We review the challenges of the ongoing effort to measure the ground-state HFS in μH and its impact on our understanding of the nucleon spin structure. To narrow down this search, we present a novel theory prediction obtained by scaling the measured HFS in hydrogen while leveraging radiative corrections. We also summarize recent developments in the spectroscopy of simple atomic and molecular systems and emphasize how they allow for precise determinations of fundamental constants, bound-state QED tests, and New Physics searches.

中文翻译：

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渺子氢进出的质子结构


μ 子原子的激光光谱最近被用于以前所未有的精度探测轻原子核的特性。我们介绍了类氢原子中的核效应、核子结构量（形状因子、结构函数、极化率）以及它们在μ子氢（μH）的兰姆位移和超精细分裂（HFS）中的影响。提出了 Lamb 偏移和 HFS （以 μH 为单位）的最新理论预测。我们回顾了正在进行的以 μH 为单位的基态 HFS 测量工作所面临的挑战及其对我们理解核子自旋结构的影响。为了缩小搜索范围，我们提出了一种新的理论预测，该预测是通过在利用辐射校正的同时缩放氢中测得的 HFS 获得的。我们还总结了简单原子和分子系统光谱学的最新发展，并强调了它们如何允许精确测定基本常数、束缚态 QED 测试和新物理学搜索。