Families of structures on spherical fibrations

Let SF(n) be the usual monoid of orientation- and base point-preserving self-equivalences of the n-sphere S-n. If Y is a (right) SF(n)-space, one can construct a classifying space B(Y, SF(n), *)=B_n for S^n-fibrations with Y-structure, by making use of the two-sided bar construction. Let k: B_n--> BSF(n) be the forgetful map. A Y-structure on a spherical fibration corresponds to a lifting of the classifying map into B_n. Let K_i=K(Z_2, i) be the Eilenberg-Mac Lane space of type (Z_2, i). In this paper we study families of structures on a given spherical fibration. In particular, we construct a universal family of Y-structures, where Y=W_n is a space homotopy equivalent to \Pi _(i greater than or equal to1) K_i. Applying results due to Booth, Heath, Morgan and Piccinini, we prove that the universal family is a spherical fibration over the space map{B_n, B_n} x B_n. Furthermore, we point out the significance of this space for secondary characteristic classes. Finally, we calculate the cohomology of B_n.