Glue in the pomeron from nonlinear $k_\perp$-factorization

We derive the nonlinear $k_\perp$-factorization for the spectrum of jets in high-mass diffractive deep inelastic scattering as a function of three hard scales – the virtuality of the photon $Q^2$, the transverse momentum of the jet and the saturation scale $Q_A$. In contrast to all other hard reactions studied so far, we encounter a clash between the two definitions of the glue in the pomeron – from the inclusive spectrum of leading quarks and the small-$\beta$ evolution of the diffractive cross section. This clash casts a further shadow on customary applications of the familiar collinear factorization to a pQCD analysis of diffractive deep inelastic scattering.