Moduli curves of supersingular K3 surfaces in characteristic 2 with Artin invariant 2

We construct explicitly moduli curves of polarized supersingular K3 surfaces in characteristic 2 with Artin invariant 2. As an application, we detect a "jump" phenomenon in a family of automorphism groups of supersingular K3 surfaces with a constant N\'eron-Severi lattice.
Comment: 58 pages, 1 figure