  We calculate the light cone wave functions for the QCD Fock components in a
transverse virtual photon necessary for applications at next-to-leading order
in the QCD coupling, including quark masses. We present a detailed calculation
of both the one loop wave function for the quark-antiquark Fock component and
the tree level wave function for the quark-antiquark-gluon Fock component. The
quark masses are renormalized in the pole mass scheme, satisfying constraints
from the requirement of Lorentz invariance. In particular the quark Pauli form
factor at NLO is recovered from the on-shell limit of the quark-antiquark Fock
component. We use our result to calculate the next-to-leading order correction
to the high energy deep inelastic scattering (DIS) transverse structure
function on a dense target in the dipole factorization framework. Together with
our earlier result for longitudinal photons, this completes the calculation of
the total deep inelastic scattering cross section in the dipole picture with
massive quarks at next-to-leading order, enabling a comparison with
experimental data.
