  We present an analysis of unpolarized Drell-Yan pair production in
pion-nucleus scattering with a particular focus into the pion dynamics. The
study consists in analyzing the effect of the partonic longitudinal and,
especially, transverse distributions of the pion in a Nambu--Jona-Lasinio (NJL)
framework, with Pauli-Villars regularization. In order to consistently take
into account the QCD evolution effects, we have estimated the hadronic scale
corresponding to the NJL model's degrees of freedom through a minimization
procedure at NLO: The NLO evolved pion distributions have been compared to
rapidity differential Drell-Yan cross sections data. That hadronic scale so
determined represents the only free parameter in our approach. The NJL
transverse momentum PDF, evolved up to next-to-leading logarithmic accuracy, is
then tested against the transverse momentum spectrum of dilepton pairs up to a
transverse momentum of 2 GeV. We found a fair agreement with available
pion-nucleus data. We find sizable evolution effects on the shape of the
distributions and on the generated average transverse momentum of the dilepton
pair.
