(8) |

*T*_{0}^{z}' is the upward continuation operator at depth*z*.

We can then obtain the perturbation in slowness from the perturbation in wavefield by applying the adjoint of the scattering operator:

(9) |

Equations (6) and (7) for the forward operator and equations (8) and (9) for the adjoint operator express the linear relation established between the perturbation in slowness () and the perturbation in image ().

6/1/1999