手征微扰理论研究重子的电磁性质

The electromagnetic properties of the nucleons have always been important issues of widespread concern, the electromagnetic properties, especially the electromagnetic radii and electromagnetic polarizability of the recently observed doubly heavy baryons in 2017, are more important issues that need to be further studied by theorists. Studying the electromagnetic properties of the baryons not only help us to understand the internal structure of the baryons, but also may be useful for future experimental measurements. This project aims to use heavy baryon chiral perturbation theory combined with the quark model and vector meson dominance model to investigate the electromagnetic properties of heavy baryon systematically, which breaks the tradition of taking experimental data as input in previous calculation. We will extend this method to investigate the electromagnetic properties of singly heavy baryons and decuplet baryons. The analytical results in this project may also be useful to the possible chiral extrapolation of the lattice simulations.

核子的电磁性质一直是人们广泛关注的重要问题，2017年新发现的双重味重子的电磁半径和电磁极化率等电磁性质更是亟待理论家们深入研究的重要问题。对这些重子电磁性质的理论研究不但有助于我们深入了解重子的内部结构，更是可以为未来实验上的直接测量提供帮助。本项目拟以重重子手征微扰理论为基础，结合夸克模型和矢量介子为主模型，突破以往计算需要以实验数据作为输入的传统，对双重味重子的电磁半径和电磁极化率等电磁性质进行系统的计算，并将此方法推广到单重味重子和十重态重子的电磁性质研究，本项目研究解析结果将为未来格点量子色动力学的手征外推提供必要的动力学参考。

近年来，实验上发现了大量的重味重子和奇特强子态，在国家自然科学基金委的资助下，项目组成员利用手征微扰理论和夸克模型对双重味重子和奇特强子态展开了理论研究工作。在重味重子手征微扰理论的框架下，我们系统研究了双重味重子的质量和电磁性质，为相关理论和实验研究提供了重要参考，相关成果发表在 Phys. Rev. D和 Commun. Theor. Phys 。此外，我们还利用夸克模型计算了隐粲五夸克态的磁矩，相关结果有助于理解五夸克态的内部结构，文章发表在Chin. Phys. C ，另有两篇文章正在投稿中。