UNIFIED BFKL AND GRIBOV-LIPATOV-ALTARELLI-PARISI DESCRIPTION OF F-2 DATA

We argue that the use of the universal unintegrated gluon distribution and the k(T) (or high energy) factorization theorem provides the natu ral framework for describing observables al small x. We introduce a co upled pair of evolution equations for the unintegrated gluon distribut ion and the sea quark distribution which incorporate both the resummed leading In(1/x) BFKL contributions and the resummed leading In(Q(2)) GLAP contributions. We solve these unified equations in the perturbati ve QCD domain using simple parametric forms of the nonperturbative par t of the integrated distributions. With only two (physically motivated ) input parameters we find that this k(T) factorization approach gives an excellent description of the measurements of F-2(x,Q(2)) at DESY H ERA. In this way the unified evolution equations allow us to determine the gluon and sea quark distributions and, moreover, to see the x dom ain where the resummed In(1/x) effects become significant. We use k(T) factorization to predict the longitudinal structure function F-L(x,Q( 2)) and the charm component of F-2(x,Q(2)).