  We present a solution to the problem of reflection/refraction of a polarized
Gaussian beam on the interface between two transparent media. The transverse
shifts of the beams' centers of gravity are calculated. They always satisfy the
total angular momentum conservation law for beams, however, in general, do not
satisfy the conservation laws for individual photons in consequence of the lack
of the ``which path'' information in a two-channel wave scattering. The field
structure for the reflected/refracted beam is analyzed. In the scattering of a
linearly-polarized beam, photons of opposite helicities are accumulated at the
opposite edges of the beam: this is the spin Hall effect for photons, which can
be registered in the cross-polarized component of the scattered beam.
