ar X iv : h ep - p h / 02 07 05 8 v 2 9 A ug 2 00 2 Saturation and Wilson Line Distribution

We introduce a Wilson line distribution function W τ (v) to study gluon saturation at small Feynman x F , or large τ = ln(1/x F ). This new distribution can be obtained from the distribution Wτ (α) of the Color Glass Condensate model and the JIMWLK renormalization group equation. W τ (v) is physically more relevant, and mathematically simpler to deal with because of unitarity of the Wilson line v. A JIMWLK equation is derived for W τ (v); its properties are studied. These properties are used to complete Mueller’s derivation of the JIMWLK equation, though for W τ (v) and not Wτ (α). They are used to derive a generalized Balitsky-Kovchegov equation for higher multipole amplitudes. They are also used to compute the unintegrated gluon distribution at x F = 0, yielding a completely flat spectrum in transverse momentum squared k, with a known height. This is similar but not identical to the mean field result at small k.