K-K excitations on AdS5 x S5 as N = 4 "primary" superfields

We show that the K-K spectrum of IIB string on AdS(5) x S-5 is described by 'twisted chiral" N = 4 superfields, naturally described in "harmonic superspace'', obtained by taking suitable gauge singlets polynomials of the D3-brane boundary SU(n) superconformal field theory. To each p-order polynomial is associated a massive K-K short representation with 256 x 1/12p(2)(p(2) - 1) states. The p = 2 quadratic polynomial corresponds to the "supercurrent multiplet" describing the "massless" bulk graviton multiplet. (C) 1998 Elsevier Science B.V. All rights reserved.