FL proton structure function from the unified DGLAP/BFKL approach

We compute the longitudinal proton structure function F-L from the k(T) factorization scheme, using the unified DGLAP/BFKL resummation approach at small x for the unintegrated gluon density. The differences between the k(T) factorization, collinear factorization, and dipole approaches are analyzed and discussed. The comparisons with the DESY collider HERA data are made and predictions for the proposed large hadron-electron collider are also provided.