Displacement (left) and oscillation period (right) as functions of average density. Black crosses correspond to simulations of tubes with uniform density and an amplitude of the initial perturbation given by V₀ = 0.05c_A. Red symbols represent the results with a Lorentzian profile and V₀ = 0.05c_A. Blue diamonds represent simulations of tubes with uniform density but an initial kinetic energy that is the same as the cases with the Lorentzian profile.