Initial and boundary conditions

Assuming the slowness around the source is constant s₀, we can find following initial conditions:  

$$\left\{ \begin{array} {lll} p(0,\theta,x_0) & = & -s_0\sin \... ...p_\theta(0,\theta,x_0) & = & -s_0\cos \theta.\end{array}\right.$$ (6)

The boundary conditions on two sides of the model are simple. One can assume outgoing rays and use one-sided finite-differences.