摘要：

The recent measurements on exclusive backward-angle electroproduction of mesons from Jefferson Lab electron-proton fixed-target scattering experiments above the resonance region, hint on a new domain of applicability of QCD collinear factorization framework in the special u-channel kinematics regime. Within this kinematics, the collinear factorized description of hard exclusive meson electroproduction reactions involves a new class of non-perturbative quantities known as the nucleon-to-meson Transition Distribution Amplitudes (TDAs). These TDAs share common features both with generalized parton distributions (GPDs) and baryon distribution amplitudes (DAs) and encode valuable new information on hadronic structure. Thanks to the pioneering experimental efforts, the interest of studying hadron structure through u-channel meson production observables have grown significantly. In this presentation, a brief overview of the theoretical status of the TDA framework will be given along with the its validating evidences observed by the JLab 6 GeV measurements; later section of the talk will introduce a pathway to further explore u-channel observables from JLab 12 GeV Hall C program to the future Electron Ion Colliders (EIC and EICC).

报告人简介：

李文亮，美国纽约石溪大学博士后。2010年本科毕业于英国肯特大学，2017年在加拿大Regina大学获得博士学位，先后在威廉玛丽学院、石溪大学任博士后。长期在美国杰斐逊国家实验室从事高能核物理实验方面的研究工作，主要研究方向为强子结构、背散射角物理。2020年荣获杰斐逊科学协会博士后奖。近5年以主要作者在国际权威物理期刊发表近20篇论文，并多次受邀在国际学术会议做大会邀请报告。目前为电子离子对撞机(EIC)和中国电子离子对撞机(EicC)背散射物理协调人，并参与撰写EIC黄皮书。