Speaker: Prof. Marek Karliner, Tel Aviv University

Host: Prof. Yang Zhengwei, Peking University

Time: 15:00-16:00 p.m., June 2, 2023, GMT+8

Venue: Scan the QR code to watch online


Abstract:

Quarks are the point-like fundamental building blocks of hadrons, strongly-interacting particles. Quarks were first suggested by Gell-Mann and Zweig, to explain patterns observed in the hadronic spectra. Their existence has since been conclusively established by a series of subsequent beautiful experiments, recognized by several Nobel Prizes. Quarks are confined into hadrons by the strong interactions. Typical hadrons are baryons, like the proton and the neutron, consisting of three quarks, or mesons containing a quark and an antiquark.

Quantum Chromodynamics (QCD), the theory of strong interactions also allows for the existence of unusual, "exotic" hadrons, such as tetraquarks and pentaquarks. The discovery of dozens of exotic hadrons during the past 20 years has led to a renaissance in hadron spectroscopy. In July 2021 the LHCb Collaboration announced the discovery of a new type of exotic hadron -- a doubly-charmed tetraquark $T_{cc}^+$, whose mass agrees precisely with a 2017 theoretical prediction.  I will discuss the recent related experimental and theoretical developments regarding new types of hadrons involving heavy quarks: tetraquark and pentaquark hadronic molecules, doubly heavy baryons, stable tetraquarks and others.

Source: School of Physics