Abstract. The generic polarized $K3$ surface (S, h) of genus 16, that is, (h^2)=30, is described in a certain compactifeid moduli space \mathcal{T} of twisted cubics in P^3, as a complete intersection with respect to an almost homogeneous vector bundle of rank 10. As corollary we prove the unirationality of the moduli space \mathcal{F}_{16} of such K3 surfaces.
Abstract. The Igusa quartic has a morphism of degree 8 onto itself. Via this self-morphism, the Satake compactification of the moduli of principally polarized abelian surfaces with Goepel triples (as well as usual p.p.a.s.'s with full level-2 structures) is isomorphic to the Igusa quartic. We also determine the action of Fricke involution on the moduli.
14) page 24, line 8 The coefficient "3" of the middle term in the right hand side should read "6".
Last modified: May 14, 2014.