Angular ordering effects in TMD parton distribution functions and Drell-Yan $q_{\bot}$ spectra

We present new results of our studies of soft-gluon angular ordering effects onthe evolution of both collinear and transverse momentum dependent (TMD) partondistribution functions, and discuss their implications for precision predictionsof Drell-Yan transverse momentum spectra at the LHC. Our method is based on theparton branching (PB) approach. We compare this with the implementation ofangular ordering in the Kimber-Martin-Ryskin-Watt (KMRW) approach and with theCollins-Soper-Sterman (CSS) approach. We illustrate numerically the effects ofdifferent ordering scenarios (p⊥, angular ordering), including definitions ofthe soft-gluon resolution scale and scale in the running coupling, on thetheoretical accuracy of predictions in the low transverse momentum region ofDrell-Yan spectra measured at the LHC.