Regular Article - Theoretical Physics
Study of QCD dynamics using small systems
Department of Physics, Indian Institute of Technology Indore, Simrol, 453552, Indore, India
2 Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, 700064, Kolkata, India
Accepted: 18 May 2021
Published online: 16 June 2021
The multiplicity, finite system size and collision energy dependence of heat capacity (), conformal symmetry breaking measure (CSBM) and speed of sound () have been investigated using ALICE data for collisions at = 7 TeV. The aim of this study is to ascertain the possibility of formation of a thermalized medium in such collisions. We find that there is a threshold in charged particle multiplicity beyond which , CSBM and attain plateau. The presence of such threshold in multiplicity is further reflected in the variation of these quantities with center-of-mass energy (). In order to have a grasp on experimentally obtained results, variation of average transverse momentum with multiplicity has also been studied. The experimental results have been contrasted with PYTHIA8 and it is found that PYTHIA8 is inadequate to explain the features reflected in these quantities, thereby indicating the possibility of thermalization in such small system. It is also observed that the finite size effects alone cannot explain the non-extensive nature of particle spectra in collisions.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021