TMDs, universality and factorization
  We present a short overview on transverse momentum dependent parton distribution and fragmentation functions, giving their partonic interpretation and ways to access them. We then discuss the issue of their universality and its connection to factorization in perturbative QCD. 
Umberto D'Alesio (Dipartimento di Fisica, Universita' di Cagliari, and   INFN, Sezione di Cagliari, Cittadella Universitaria...
hep-ph