On product affine hyperspheres in R^n+1

In this paper,we study locally strongly convex affine hyperspheres in the unimodular affine space Rn+1 which,as Riemannian manifolds,are locally isometric to the Riemannian product of two Riemannian manifolds both possessing constant sectional curvature.As the main result,a complete classification of such affine hyperspheres is established.Moreover,as direct consequences,3-and 4-dimensional affine hyperspheres with parallel Ricci tensor are also classified.