Thesis

Novel hard probes of the primordial QGP

• Call:

  IDPASC Portugal - PHD Programme 2019

• Academic Year:

  2019 / 2020

• Domain:

  Experimental Particle Physics

• Supervisor:

  Nuno Leonardo

• Co-Supervisor:

  Joao Seixas

• Institution:

  Instituto Superior Técnico

• Host Institution:

  Laboratório de Instrumentação e Física Experimental de Partículas

• Abstract:

  Ultra-relativistic collisions of heavy nuclei at the LHC recreate droplets of the primordial medium that permeated the universe microseconds after the big bang. Particles are expected to loose energy while traversing this hot and dense soup of quarks and gluons (QGP). Traditionally, this phenomenon has been explored in an inclusive fashion (e.g. “jet quenching”). For the first time, however, with LHC Run2 data collected by the CMS detector, we are able to reconstruct the actual hadron decays, despite the very challenging environment. In this thesis project the student will explore the large data set of lead-lead collisions collected in the last LHC run (November 2018), leading to the first observation of heavy-flavour mesons (B) and their suppression in the QGP. The observation of the rare B signals in the busy collision environment will be achieved developing dedicated machine learning algorithms. These novel probes will facilitate unique information on the flavour dependence of energy loss and the underlying properties of the QGP medium.