Collective nuclear vibrations and initial state shape fluctuations in central Pb+Pb collisions: resolving the $v_2$ to $v_3$ puzzle

Abstract

We have studied, for the first time, the influence of the collective quantum effects in the nuclear wave functions on the azimuthal anisotropy coefficients ǫ2,3 in the central Pb+Pb collisions at the LHC energies. With the help of the energy weighted sum rule we demonstrate that the classical treatment with the Woods-Saxon nuclear density overestimates the mean square quadrupole moment of the 208 Pb nucleus by a factor of ∼ 2.2. The Monte-Carlo Glauber simulation of the central Pb+Pb collisions accounting for the restriction on the quadrupole moment leads to ǫ2/ǫ3 ≈ 0.8 which allows to resolve the v2-to-v3 puzzle.

Predictions for flow harmonic distributions and flow factorization ratios at RHIC

“…5, similar results hold for NeXus. This effect is more pronounced in central collisions, which also happens to coincide with the v 2 to v 3 puzzle [86][87][88][89][90][91][92]. Additionally, it also appears that our theoretical calculations demonstrate the largest suppression compared to the data when p (a)…”