  Some unexplored decoherence aspects within the Caldeira-Leggett master
equation are analyzed and discussed. The decoherence process is controlled by
the two environment parameters, the relaxation rate or friction and the
temperature, leading to a gradual transition from the quantum to classical
regime. Arrival time distributions, nonminimum-uncertainty-product or
stretching Gaussian wave packets, identical particles and diffraction in time
display interesting features during the decoherence process undergone by the
time dependent interference patterns. We show that the presence of a constant
force field does not affect the decoherence, {\it positive} values of the
stretching parameter reduces the rate of decoherence, the symmetry of the wave
function for identical particles plays no role when open dynamics are
considered; and diffraction in time and space is gradually washed out by
increasing the temperature and/or relaxation rate in the zero dissipation limit
within the so-called quantum shutter problem.
