The new HERA data and the determination of the infrared behaviour of the BFKL amplitude

I this talk I discuss the new HERA data on the structure function image obtained from a combination of H1 and ZEUS results. Their high precision allows to determine the infrared behaviour of the BFKL forward amplitude for gluon–gluon scattering. This amplitude leads to an excellent description of the new data at low values of x (<0.01) and at the same time determines the unintegrated gluon density inside the proton, for squared transverse momenta of the gluon less than image. The phases of this amplitude are sensitive to the non-perturbative gluonic dynamics and to the presence of Beyond-the-Standard-Model particles at very high energies.