Wang Yu-Fei, Döring Michael, Hergenrather Jackson, Mai Maxim, Mart Terry, Meißner Ulf-G, Rönchen Deborah, Workman Ronald
Institute for Advanced Simulation (IAS-4), <a href="https://ror.org/02nv7yv05">Forschungszentrum Jülich</a>, 52425 Jülich, Germany.
School of Nuclear Science and Technology, <a href="https://ror.org/05qbk4x57">University of Chinese Academy of Sciences</a>, Beijing 101408, China.
Phys Rev Lett. 2024 Sep 6;133(10):101901. doi: 10.1103/PhysRevLett.133.101901.
Hadronic resonances emerge from strong interactions encoding the dynamics of quarks and gluons. The structure of these resonances can be probed by virtual photons parametrized in transition form factors. In this study, twelve N^{*} and Δ transition form factors at the pole are extracted from data with the center-of-mass energy from πN threshold to 1.8 GeV, and the photon virtuality 0≤Q^{2}/GeV^{2}≤8. For the first time, these results are determined from a simultaneous analysis of more than one state, i.e., ∼10^{5} πN, ηN, and KΛ electroproduction data. In addition, about 5×10^{4} data in the hadronic sector as well as photoproduction serve as boundary conditions. For the Δ(1232) and N(1440) states our results are in qualitative agreement with previous studies, while the transition form factors at the poles of some higher excited states are estimated for the first time. Realistic uncertainties are determined by further exploring the parameter space.
强子共振态源于编码夸克和胶子动力学的强相互作用。这些共振态的结构可以通过以跃迁形状因子参数化的虚光子来探测。在本研究中，从质心能量从πN阈值到1.8 GeV以及光子虚能0≤Q²/GeV²≤8的数据中提取了十二个处于极点的N*和Δ跃迁形状因子。首次通过对不止一个态（即约10⁵个πN、ηN和KΛ电产生数据）的同时分析确定了这些结果。此外，强子扇区中约5×10⁴个数据以及光产生数据用作边界条件。对于Δ(1232)和N(1440)态，我们的结果与先前的研究定性一致，而一些较高激发态极点处的跃迁形状因子是首次估计。通过进一步探索参数空间确定了实际的不确定性。
