  We investigate the diurnal modulation of the event rate for dark matter
scattering on solid targets arising from the directionally dependent defect
creation threshold energy. In particular, we quantify how this effect would
help in separating dark matter signal from the neutrino background. We perform
a benchmark analysis for a germanium detector and compute how the reach of the
experiment is affected by including the timing information of the scattering
events. We observe that for light dark matter just above the detection
threshold the magnitude of the annual modulation is enhanced. In this mass
range using either the annual or diurnal modulation information provides a
similar gain in the reach of the experiment, while the additional reach from
using both effects remains modest. Furthermore, we demonstrate that if the
background contains a feature exhibiting an annual modulation similar to the
one observed by DAMA experiment, the diurnal modulation provides for an
additional handle to separate dark matter signal from the background.
