Studies of the spectrum of hadrons and their structure in experiments with electromagnetic probes offer unique insight into many facets of the strong interaction in the regime of large quark-gluon running coupling, i.e. the regime of strong QCD. The experimental program within Hall B at Jefferson Laboratory based on data acquired with the CLAS spectrometer using electron and photon beams with energies up to 6 GeV has already considerably extended the scope of research in hadron physics in joint efforts between experiment and phenomenological data analysis. Impressive progress in relating the hadron structure observables inferred from the data to the strong QCD mechanisms underlying hadron mass generation has been achieved in the past decade. These results will be considerably extended with data from the experimental program with the new CLAS12 spectrometer that has begun data taking using electron beams with energies up to 11 GeV. With this extended kinematic reach the structure of nucleon resonances will be probed at the highest photon virtualities ever achieved in the studies of exclusive electroproduction, which will allow for the exploration of the distance scale where>98% of light hadron mass emerges from QCD in the transition of the strong interaction from the regime of quark-gluon confinement to perturbative QCD.

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来自 CLAS 和 CLAS12 的激发核子结构研究的强大 QCD 见解

强子光谱及其结构在电磁探测器实验中的研究提供了对大夸克-胶子运行耦合机制（即强 QCD 机制）中强相互作用的许多方面的独特见解。杰斐逊实验室 B 厅内的实验项目基于 CLAS 光谱仪使用能量高达 6 GeV 的电子和光子束获取的数据，已经大大扩展了强子物理学的研究范围，通过实验和现象学数据分析的共同努力。在过去的十年中，从数据中推断出的强子结构可观测量与强子质量产生背后的强 QCD 机制相关，取得了令人瞩目的进展。新 CLAS12 光谱仪已开始使用能量高达 11 GeV 的电子束进行数据采集，实验程序的数据将大大扩展这些结果。有了这个扩展的运动学范围，核子共振的结构将在独家电生产研究中达到的最高光子虚拟性下探测，这将允许探索距离尺度，其中> 98% 的轻强子质量从 QCD 中出现强相互作用从夸克-胶子约束机制到微扰 QCD 的转变。