  In transmission electron energy-loss spectroscopy, the cross section in 2D is
quenched by kinematic effects once the momentum transfer becomes smaller than a
critical value set by $q_z$, the momentum loss parallel to the beam. Our highly
momentum ($\Delta q = 0.02$~\r{A}$^{-1}$) and energy ($\Delta E = 45$~meV)
resolved setup is instrumental on delivering the unprecedented experimental
verification of quenched 2D EEL spectra on freestanding graphene at momentum
transfers $q$ below $0.06$\r{A}$^{-1}$. We retrieve the intrinsic uniform
dielectric response of graphene from measured spectra by quantifying the
kinematic suppression.
