  The emission of collinear radiation off an elementary lepton can be
factorised from the hard scattering process by introducing Parton Distribution
Functions of a Lepton (LePDF), which, contrary to protons, can be derived from
first principles. In case of multi-TeV lepton colliders, such as the muon
colliders currently being proposed, the complete structure of Standard Model
interactions must be taken into account. In this work we solve numerically the
corresponding DGLAP equations at the double-log order and provide public files
with LePDFs for both muons and electrons, including polarisation effects. We
discuss several interesting aspects of the resulting PDFs and compare them with
the Effective Vector Approximation, showing that the latter fails to describe
well the vector bosons PDFs at small momentum fractions, unless it is extended
to higher orders.
