Unitarization of gluon distribution in the doubly logarithmic regime at high density - art. no. 034007

We analyze the general nonlinear evolution equations for multigluon correla tors derived in a previous paper by restricting ourselves to a double logar ithmic region. In this region our evolution equation becomes local in trans verse momentum space and amenable to simple analysis. It provides a complet e nonlinear generalization of the Gribov-Levin-Ryskin equation. We find tha t the full double log evolution at high density becomes strikingly differen t from its linear doubly logarithmic Dokshitzer-Gribov-Lipatov-Alterelli-Pa risi counterpart. An effective mass is induced by the nonlinear corrections which at high densities slows down the evolution considerably. We show tha t at small values of impact parameter the gluonic density grows as a logari thm of energy. At higher values of impact parameter the growth is faster, s ince the density of gluons is lower and nonlinearities are less important. [S0556-2821(99)02003-2].