J/$\psi$ production measurements at mid-rapidity using the ALICE detector at the LHC

Abstract

Charmonium production is highly sensitive to the hot and dense medium created in (ultra)-relativistic heavy-ion collisions, known as the Quark-Gluon Plasma (QGP). Measurements of the J/$\psi$ production serve as important tools for studying the properties of this medium. In addition to QGP effects, the J/$\psi$ production is modified by the presence of cold nuclear matter (CNM) effects such as shadowing or parton energy loss. These effects are studied in proton-nucleus collisions where no QGP formation is expected. In order to quantify how the J/$\psi$ production is modified by the medium, the vacuum production is modelled in proton-proton (pp) collisions and used as a reference for heavy-ion and proton-nucleus collisions. Measurements in pp collisions also serve as important tools for testing Quantum Chromodynamic (QCD) based models in both perturbative and non-perturbative regimes. The ALICE detector has the unique capability of measuring the J/$\psi$ at mid-rapidity through the di-electron channel down to zero transverse momentum. In this contribution a selection of the newest J/$\psi$ measurements at mid-rapidity performed by the ALICE Collaboration during the LHC Run 2 period will be discussed.