We propose a simple parametrization for the deep-inelastic diffractive cross
section. It contains the contribution of qqˉ production to both the
longitudinal and the transverse diffractive structure functions, and of the
production of qqˉg final states from transverse photons. We start from
the hard region and perform a suitable extrapolation into the soft region. We
test our model on the 1994 ZEUS and H1 data, and confront it with the H1
conjecture of a singular gluon distribution.Comment: 24 pages, LaTeX, figures included using epsfi