Erratum: Initial fields and instability in the classical model of the heavy-ion collision

We correct a mistake in the analytical expression for the energy density given in Phys. Rev. C76, 021902 (2007) [arXiv:0704.3625 [hep-ph]]. The expression should be multiplied by 16. One question then arises; how could it be possible to explain this difference between the analytical and numerical results in the same model if both are correct? We find a subtle problem in the treatment of the randomness of the color source along the longitudinal direction and the treatment of the longitudinal extent of the color source.