  The IceCube Neutrino Observatory at the South Pole detects Cherenkov light
emitted by charged secondary particles created by primary neutrino
interactions. Double pulse waveforms can arise from charged current
interactions of astrophysical tau neutrinos with nucleons in the ice and the
subsequent decay of tau leptons. The previous 8-year tau double pulse analysis
found three tau neutrino candidate events. Among them, the most promising one
observed in 2014 is located very near the dust layer in the middle of the
detector. A posterior analysis on this event will be presented in this paper,
using a new ice model treatment with continuously varying nuisance parameters
to do the targeted Monte Carlo re-simulation for tau and other background
neutrino ensembles. The impact of different ice models on the expected signal
and background statistics will also be discussed.
