  The charged-particle's final state spectrum is derived from an analytic
perturbative solution for the relativistic viscous hydrodynamics. By taking
into account the longitudinal acceleration effect in relativistic viscous
hydrodynamics, the pseudorapidity spectrum describes well the nucleus-nucleus
colliding systems at RHIC and LHC. Based on both the extracted longitudinal
acceleration parameters $\lambda^{*}$ and a phenomenological description of the
$\lambda^{*}$, the charged-particle's pseudorapidity distributions for
$\sqrt{s_{NN}}$ = 5.44 TeV Xe+Xe collisions are computed from the final state
expression in a limited space-time rapidity $\eta_{s}$ region.
