Left panels: dimensionless particle number density, η, as a functionof x, for three values of ξ. The bottom panel corresponds to the critical value ξ_c. Right panels: dimensionless energies per particle for the same values of ξ shown in left panels (gravitational energy due to matter, ν_M; total gravitational energy, ν_M + ν_Λ; single-particle energy, ϵ), as a functionof the dimensionless distance x. The distances x₁, x₀ and x₂ for ξ_c are marked in the bottom right panel.