  We formulate a light-front spectator model for the proton incorporating the
gluonic degree of freedom. In this model, at high energy scattering of the
proton, the active parton is a gluon and the rest is viewed as a
spin-$\frac{1}{2}$ spectator with an effective mass. The light front wave
functions of the proton are constructed using a soft wall AdS/QCD prediction
and parameterized by fitting the unpolarized gluon distribution function to the
NNPDF3.0nlo data set. We investigate the helicity distribution of gluon in this
model. We find that our prediction for the gluon helicity asymmetry agrees well
with existing experimental data and satisfies the perturbative QCD constraints
at small and large longitudinal momentum regions. We also present the
transverse momentum dependent distributions (TMDs) for gluon in this model. We
further show that the model-independent Mulders-Rodrigues inequalities are
obeyed by the TMDs computed in our model.
