Characterizing hadronic phase in relativistic hadronic and heavy-ion collisions and study of muon puzzle in cosmic ray events with GRAPES-3 experiment

Abstract

In high-energy nuclear physics, studying heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) shows a glance into the extreme conditions that existed a few microseconds after the Big Bang. These collisions, described by the collision of heavy atomic nuclei at ultrarelativistic velocities, aim to recreate and study the properties of quark-gluon plasma (QGP). QGP is a state of matter where quarks and gluons are freed from their usual confinement within hadrons and move freely within a volume larger than the hadrons. This plasma acts like a nearly perfect fluid in nature. Several signatures of experimental and theoretical analyses suggest the formation of QGP. Studies have observed strong collective flow in particle distributions, indicating the QGP’s hydrodynamic behavior and rapid evolution and cooling phases. Likewise, phenomena such as strangeness enhancement, jet quenching, and suppression of quarkonia states act as an indirect probe into the dynamics and thermalization processes within the QGP medium.