Probing the low transverse momentum domain of Z production with novel variables

The measurement of the low transverse momentum region of vector boson pro- duction in Drell-Yan processes has long been invaluable to testing our knowledge of QCD dynamics both beyond fixed-order in perturbation theory as well as in the non-perturbative region. Recently the Dθ collaboration have introduced novel variables which lead to im- proved measurements compared to the case of the standard QT variable. To complement this improvement on the experimental side, we develop here a complete phenomenological study dedicated in particular to the new θ* variable. We compare our study, which contains the state-of-the-art next-to-next-to-leading resummation of large logarithms and a smooth matching to the full next-to-leading order Oα 2 s result, to the experimental data and find excellent agreement over essentially the entire range of θ*, even without direct in- clusion of non-perturbative effects. We comment on our findings and on the potential for future studies to constrain non-perturbative behaviour. © SISSA 2012.