Study of Momentum Tensor Observables in Heavy-Ion Collisions

Event shape variables in heavy-ion collisions have been an important tool for QCD studies. They provide a measure of the hadronic energy-momentum flow in the final state and play an important role in determining the strong coupling constant and hadronic effects. In this study, we explore the properties associated with the momentum tensor, which does not require the determination of the event plane, to characterize geometrical features of participants from colliding nuclei. The eigenvalues of the tensor yield two observables, known as Sphericity (S) and Coplanarity (C), which can be used to quantify the event shape. Historically these observables have been used in e⁺e^- annihilation studies, and now we apply them to 200 GeV Au+Au events simulated by a multi-phase transport model (AMPT), and present the S and C values for various centrality intervals.