  The Radiative transfer coherent backscattering (RT-CB) code is extended to
apply to dense discrete random media of optically soft spherical particles.
This is achieved by utilizing the well-known static-structure-factor (SSF)
correction derived from the Percus-Yevick approximation for sticky-hard-sphere
(SHS) pair correlation function. The code is verified against the numerically
exact electromagnetic method for small spherical media consisting of
submicrometer-sized icy particles at optical wavelengths. The SSF-corrected
RT-CB method significantly improves solution accuracy, and the solution agrees
well with the numerically exact solution when the packing density is less than
20% and particles are optically soft, i.e., the refractive index of particles
is close to that of the background medium.
