Event topology dependence of J/ψ production in proton+proton collisions at √s = 13 TeV with ALICE at the LHC and study of elliptic flow in heavy-ion collisions using event shape and machine learning techniques

Abstract

Studies related to heavy-ion collisions at the most powerful particle accelerators in the world, the Large Hadron Collider (LHC) at CERN, Switzerland, and the Relativistic Heavy Ion Collider (RHIC) at BNL, USA, have primarily focused on the creation and properties of the primordial matter consisting quarks and gluons. This extremely dense and hot state of thermalized partons is also known as quark-gluon plasma (QGP). Due to the shorter lifetime of QGP, experiments rely on several indirect signatures that hint towards the formation of QGP in ultra-relativistic collisions of nuclear matter. While the formation of QGP has been established for a long time in heavy-ion collisions, its presence in small collision systems still needs to be determined. However, recent measurements of heavy-ion-like behavior in high-multiplicity pp collisions at the LHC have drawn the attention of the heavy-ion physics community. The appearance of ridge-like structures and the enhancement of strangeness add to these speculations.