  We construct an X-ray spectral model of reprocessing by a torus in an active
galactic nucleus (AGN) with a Monte Carlo simulation framework MONACO. Two
torus geometries of smooth and clumpy cases are considered and compared. In
order to reproduce a Compton shoulder accurately, MONACO includes not only free
electron scattering but also bound electron scattering. Raman and Reyleigh
scattering are also treated, and scattering cross sections dependent on
chemical states of hydrogen and helium are included. Doppler broadening by
turbulence velocity can be implemented. Our model gives consistent results with
other available models, such as MYTorus, except for differences due to
different physical parameters and assumptions. We studied the dependence on
torus parameters for Compton shoulder, and found that a intensity ratio of
Compton shoulder to line core mainly depends on the column density, inclination
angle, and metal abundance. For instance, an increase of metal abundance makes
the Compton shoulder relatively weak. Also, shape of Compton shoulder depends
on the column density. Furthermore, these dependences become different between
smooth and clumpy cases. Then, we discuss the possibility of ASTRO-H SXS
spectroscopy of Compton shoulder in AGN reflection spectra.
