First determination of hybrid-quarkonium mixing and hybrid spin-dependent potentials with lattice gauge theory

• Applicants: Professor Dr. Antonio Vairo; Professor Dr. Marc Wagner
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550503820

The main aim of the project is to carry out the first lattice gauge theory computation of the 1/m hybrid-quarkonium mixing potentials and the 1/m hybrid spin-dependent potentials for the lowest quarkonium hybrids, whose gluons carry J^PC quantum numbers 1^+- corresponding to the potential quantum numbers Pi_u and Sigma_u^- in molecular notation. The project also envisages some phenomenological applications, which require these mixing and spin-dependent potentials. They include computing the spectrum of ordinary quarkonium and quarkonium hybrids in a single effective field theory setup, i.e. from a single coupled-channel Schrödinger equation comprising 1/m corrections. Another phenomenological application consists in computing hybrid to quarkonium transition widths by explicitly accounting for the mixing. Comparing the obtained results with the available experimental data for the XYZ states may allow the identification of some of these states as hybrids, i.e. states with a dominant hybrid component.

• DFG Programme: Research Grants