报告题目：Hidden charm pentaquark states and $\Sigma_c\bar{D}^{(*)}$ interaction in chiral perturbation theory

报告人：孟璐博士  北京大学

 报告时间：2019年6月6日（星期四）上午10:30

报告地点：物理楼313

报告摘要：In 2015, the LHCb Collaboration discovered two pentaquark candidates Pc(4380) and P_c(4450). Very recently, the LHCb Collaboration reported the new results about pentaquarks. The previously reported Pc(4450) was resolved into two narrow states Pc(4440) and P_c(4457). Besides, a new state Pc(4312) was observed. We employ the heavy hadron chiral perturbation theory (HHChPT) to calculate the $\Sigma_c\bar{D}^{(*)}$ potentials to the next-to-leading order. The contact, the one-pion exchange and the two-pion exchange interactions are included. Besides, the mass splittings between the heavy quark spin symmetry (HQSS) multiplets are kept in calculations. Our result shows that neglecting the heavy quark symmetry (HQS) violation effect may be misleading to predict the potentials between the charmed hadrons. We perform numerical analysis with the coupled-channel effect. We notice that the three Pc states can be reproduced as molecular states simultaneously in a large region of parameters. Our analytical results can be used for the chiral extrapolations in lattice QCD. With the lattice QCD results in the future as inputs, the identification of the Pc states and predictions for other systems would be more reliable.

个人简介：孟璐，北京大学在读博士生。 2015年本科毕业于山东大学。 后进入北京大学攻读博士学位，方向是强子物理理论，师从朱世琳教授。主要研究兴趣是多夸克态，手征微扰理论，强子的谱学及衰变。目前已在Physical Review D， European Physical Journal C等国际权威期刊发表学术文章10余篇，被引用100多次。