Investigating color screening in proton-nucleus collisions with complex potentials

Wen L, Du X, Shi S, Chen B. Investigating color screening in proton-nucleus collisions with complex potentials. Chinese Physics C . 2022;46(11): 114102.Color screening and parton inelastic scattering modify the heavy-quark antiquark potential in mediums consisting of particles from quantum chromodynamics (QCD), leading to the suppression of quarkonium production in relativistic heavy-ion collisions. Owing to the small charm/anti-charm (c (c) over bar) pair production number in proton-nucleus (pA) collisions, the correlation between different c (c) over bar pairs is negligible, which makes the Schrodinger equation viable for tracking the evolution of only one c (c) over bar pair. We employ the time-dependent Schrodinger equation with an in-medium c (c) over bar potential to study the evolution of charmonium wave functions in a hydrodynamic-like QCD medium produced in pA collisions. We explore different parametrizations of real and imaginary parts of the cc potential and calculate the nuclear modification factors (RpA) of J//psi and psi/(2S ) in root s(NN) = 5.02 TeV energy p-Pb collisions at the Large Hadron Collider (LHC). Comparing strong and weak screening scenarios with experimental data in this approach, we arrive at the conclusion that color screening is weak at temperatures close to the deconfined phase transition. Moreover, the imaginary part of the potential is crucial in describing the experimental data, which is consistent with widely studied semi-classical approaches, where dissociation rates are essential