The quark-gluon plasma is a new state of matter that can be formed by colliding heavy ions at ultrarelativistic velocities. From all the particles formed in these collisions, heavy quarkonium is one of the most promosing probes to obtain information about this new state of matter. One of the most succesful approaches to the study of the evolution of quarkonium in a medium is to model it as a Markovian open quantum system. Recently, it has been found using this approach that regeneration is crucial to reproduce experimental data on quarkonium excited states.
Particles and Gravitation
We propose to study the reaction pi- p —> pi- eta p, whose data have been collected by the COMPASS collaboration.Â
The goal is to develop the so-called ``finite-energy sum rules’’ for this reaction, that will allow to constraints better the production of exotic meson.Â
The student will first understand these constraints on a toy model (based on Veneziano amplitudes) and will subsequently apply them to the reaction under consideration.Â