Lecture commences at 4:00 pm in 330 Allen Building.

Dr. Alessandro Pilloni
Jefferson Lab

Title

Challenges in Hadron Spectroscopy

Abstract

Quantum Chromodynamics is universally acknowledged as the theory of strong interactions. However, the way how the fundamental constituents (quark and gluons) arrange themselves into the hadrons that are actually observed in experiments, is still a mystery. Even at a phenomenological level, the presence of multiple overlapping states leads to intricate interference patterns that make the extraction of meaningful information complicated.

In this colloquium, I will show what challenges we face every day to understand the spectrum of strong interacting particles. I will explain the basics of amplitude analysis, and how to extract physics from seemingly abstract mathematical structures. This framework allows us to convert the raw experimental data into robust physics information. I will finish showing an application to the most controversial cases, as the mysterious XYZ states in the heavy quark sector, or the elusive hybrid mesons in the light sector.