An application of transverse-momentum-dependent evolution equations in QCD

The properties and behaviour of the solutions of the recently obtained $k_t$-dependent evolution equations are investigated. When used to reproduce transverse momentum spectra of hadrons in Semi-Inclusive DIS, an encouraging agreement with data is found. The present analysis also supports at the phenomenological level the factorization properties of the Semi-Inclusive DIS cross-sections in terms of $k_t$-dependent distributions. Further improvements and possible developments of the proposed evolution equations are envisaged