Exploring the meson spectrum with 3π photoproduction and the search for the exotic hybrid meson π1(1600) at the GlueX experiment

• Applicant: Dr. Farah Noreen Afzal
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537210888

The strong force is one of the four fundamental forces in nature which governs the interactions between the fundamental constituents of nuclear matter, quarks and gluons, and is described by the theory of Quantum Chromodynamics (QCD). The generation of confined states i.e. hadrons, which are primarily classified in two configurations as baryons (three quarks) and mesons (quark-antiquark pair), is not well understood. One way to shed light on this matter is to investigate the meson spectrum. QCD allows for a much richer meson spectrum that goes beyond the quark-antiquark pair configuration. One such configuration is the class of hybrid mesons which contain excited gluonic fields that contribute to the quantum numbers of the bound state. A subset of these hybrid mesons have quantum numbers which cannot be created from a simple quark-antiquark pair and are called spin-exotic mesons. The experimental confirmation of the existence of exotic mesons is an essential direct test of QCD in the low energy sector. Within the scope of this project, the meson spectrum will be investigated through the photoproduction of three pions, using data from the GlueX experiment at Jefferson Lab, which produces hadrons using a polarized photon beam. The aim is to confirm the lightest hybrid meson, the π1(1600).

• DFG Programme: Independent Junior Research Groups