Meson Transition Form Factors (Project TFF)

介子跃迁形状因子（TFF 项目）

• 批准号: 498960712
• 负责人: Dr. Igor Danilkin
• 金额: --
• 依托单位: Institut für Kernphysik
• 依托单位国家: 德国
• 项目类别: Research Units
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/498960712?language=en
• 关键词: Meson; Transition; Form; Factors; Project

The interaction of two real or virtual photons with hadronic matter is described by transition form factors (TFFs). These do not only provide information on the internal structure of the involved hadrons, but are also necessary input to further constrain the uncertainties of the hadronic Light-by-Light contribution to the anomalous magnetic moment of the muon. The aim of Project TFF is to provide the information exploiting synergies of experimental and theoretical efforts. High-precision measurements at the A2/MAMI experiment will provide world-leading information on time-like TFFs from meson Dalitz decays. Complementary information on space-like TFFs will be obtained at the BESIII experiment in two-photon fusion reactions producing single mesons and multi-meson systems. Making use of the information, data-driven phenomenological approaches, which have already been developed based on dispersive analysis for real photons are extended to virtual photons and higher meson multiplicities in order to provide access to the relevant scalar, tensor and axial mesons. In addition, ab-initio calculations on the lattice will provide the information on double-virtual TFFs of single mesons, which is challenging to obtain from experiments. Eventually, the data obtained and tools developed in project TFF can be used to access hadron structure from a different angle by studying pion polarizabilities.

两个真实的或虚光子与强子物质的相互作用用跃迁形状因子（TFF）来描述。这些不仅提供了所涉及的强子的内部结构的信息，但也是必要的输入，以进一步限制强子光的光的贡献的μ子的异常磁矩的不确定性。TFF项目的目的是提供利用实验和理论工作的协同作用的信息。A2/MAMI实验的高精度测量将提供有关来自介子达利茨衰变的类时间TFF的世界领先信息。在BESIII实验中，将在产生单介子和多介子系统的双光子聚变反应中获得关于类空TFF的补充信息。利用这些信息，数据驱动的唯象方法，这已经发展的色散分析的基础上真实的光子扩展到虚光子和更高的介子多重性，以提供访问相关的标量，张量和轴介子。此外，在晶格上的从头计算将提供单介子的双虚TFF的信息，这是具有挑战性的从实验中获得。最终，TFF项目中获得的数据和开发的工具可以通过研究π极化率从不同的角度来访问强子结构。