  The channeling effect in crystals refers to the orientation dependence of
charged ion penetration in crystals. In direct dark matter crystalline
detectors, a channeled ion recoiling after a collision with a WIMP gives all
its energy to electrons. Thus channeling increases the ionization or
scintillation signal expected from a WIMP. Channeling is a directional effect
which depends on the velocity distribution of WIMPs in the dark halo of our
Galaxy and could lead to a daily modulation of the signal. I will present
estimates of the expected amplitude of the daily modulation in direct dark
matter detectors, both due to channeling and just due to the rotational
velocity of the Earth around itself.
