Phenomenology of the hadronic structure at small-$x$

We present exploratory studies of the proton structure via two distinct kinds of gluon densities: the transverse-momentum dependent functions, whose evolution is determined by the CSS equation, and the unintegrated gluon distribution, whose definition is given in the BFKL formalism. Our analyses are relevant for the exploration of the intrinsic motion of gluons inside protons in the small-$x$ regime, and for a comprehensive tomographic imaging of the proton at new-generation colliding facilities.Comment: 10 pages, 2 figures, 1 table, presented at the Low-$x$ Workshop, Elba Island, Italy, September 27--October 1 202