Internal Decoherence of a Gaussian Wave Packet in a Harmonic Potential
  We have studied the quantum dissipative problem of a Gaussian wave packet under the influence of a harmonic potential. A phenomenological approach to dissipation is adopted in the light of the well-known model in which the environment is composed of a bath of non-interacting harmonic oscillators. As one of the effects of the coupling to the bath is the evolution of an initially pure wave packet into a statistical mixture, we estimate the characteristic time elapsed for this to occur for different regimes of temperature, damping, and also different initial states. 
A. Cidrim, F. E. A. dos Santos, A. O. Caldeira
quant-ph