SLE eight-thirds restriction martingale (${\mathrm{SLE}}_{8/3}$)

For chordal ${\mathrm{SLE}}_{8/3}$ and an admissible hull $A$, let ${\psi }_t$ map out the image of $A$ after removing the SLE hull. Thenstopped when the trace meets $A$ is a bounded martingale. Its terminal value yields the avoidance probability