Hilbert scheme of some threefold scrolls over the Hirzebruch surface F_1
  Hilbert schemes of suitable smooth, projective manifolds of low degree which are 3-fold scrolls over the Hirzebruch surface F_1 are studied. An irreducible component of the Hilbert scheme parametrizing such varieties is shown to be generically smooth of the expected dimension and the general point of such a component is described. 
Gian Mario Besana, Maria Lucia Fania, Flaminio Flamini
math.AG