We independently develop a simulation code following the previous dynamical
Monte Carlo simulation of the diffusive shock acceleration under the isotropic
scattering law during the scattering process, and the same results are
obtained. Since the same results test the validity of the dynamical Monte Carlo
method for simulating a collisionless shock, we extend the simulation toward
including an anisotropic scattering law for further developing this dynamical
Monte Carlo simulation. Under this extended anisotropic scattering law, a
Gaussian distribution function is used to describe the variation of scattering
angles in the particle's local frame. As a result, we obtain a series of
different shock structures and evolutions in terms of the standard deviation
values of the given Gaussian scattering angular distributions. We find that the
total energy spectral index increases as the standard deviation value of the
scattering angular distribution increases, but the subshock's energy spectral
index decreases as the standard deviation value of the scattering angular
distribution increases.Comment: This article include 10 pages, 8 figures, and accepted by Astronomy
and Astrophysic
