Model comparison for initial density fluctuations in high energy heavy ion collisions

Understand

Four models for the initial conditions of a fluid dynamic description of high energy heavy ion collisions are analysed and compared.

• We study expectation values and event-by-event fluctuations in the initial transverse energy density profiles from Pb-Pb collisions.
• Specifically, introducing a Fourier-Bessel mode expansion for fluctuations, we determine expectation values and two-mode correlation functions of the expansion coefficients.
• The analytically solveable independent point-sources model is compared to an initial state model based on Glauber theory and two models based on the Color Glass Condensate framework.