  The scale factor is the effective cross section used to characterize the
measured rate of inclusive double dijet production in high energy hadron
collisions. It is sensitive to the two-parton distributions in the hadronic
projectile. In principle, the scale factor depends on the center of mass energy
and on the minimal transverse energy of the jets contributing to the double
dijet cross section. Here, we point out that proton-proton collisions at the
LHC will provide for the first time experimental access to these scale
dependences in a logarithmically wide, nominally perturbative kinematic range
of minimal transverse energy between 10 GeV and 100 GeV. This constrains the
dependence of two-parton distribution functions on parton momentum fractions
and parton localization in impact parameter space. Novel information is to be
expected about the transverse growth of hadronic distribution functions in the
range of semi-hard Bjorken x (0.001 < x < 0.1) and high resolution Q^2. We
discuss to what extent one can disentangle different pictures of the
$x$-evolution of two-parton distributions in the transverse plane by measuring
double-hard scattering events at the LHC.
