THE CCFM EQUATION AND PREDICTIONS FOR HERA PHYSICS

We solve a unified integral equation (the CCFM equation) for the gluon distribution of a proton in the small x regime. Here x is the longitu dinal momentum fraction of a gluon probed at a scale Q. The equation g enerates a gluon with a steep x(-lambda) behaviour, with lambda simila r to 0.5. We compare our solutions with, on the one hand, those that w e obtain using the double-leading-logarithm approximation to Altarelli -Parisi evolution and, on the other hand, to those that we determine f rom the BFKL equation. We examine what the consequences of this gluon evolution are for the structure function, F-2(x, Q(2)), as measured by the HERA electron-proton collider. Following this we investigate the effect of imposing an additional kinematic constraint k(T)(2) < q(T)(2 )/z, on the CCFM equation. In particular we examine its implications f or F-2(x, Q(2)) as a function of Q(2), the charm component, F-2(c)(x, Q(2)) and diffractive J/psi photoproduction.