  Collective flow in collisions between Lead nuclei at LHC are influenced by
random initial state fluctuations, especially for odd harmonics. Here we extend
fluctuation studies to longitudinal fluctuations, which may have significant
effect on the rapidity distribution of odd harmonics. Furthermore center of
mass rapidity fluctuations are measurable, but not yet analysed. Here in the
PACIAE parton and hadron molecular dynamics model we make an analysis of
initial state fluctuations. As previous analyses discussed mainly the effects
of fluctuations on eccentricity and the elliptic flow we pay particular
attention to the fluctuations of the Center of Mass rapidity of the system,
which is conservatively estimated in our model as {\Delta}y_{CM} = 0.1, by
neglecting all pre-equilibrium emission effects that are increasing the y_{CM}
fluctuations.
