In transmission electron energy loss (EEL) spectroscopy, the cross section in two dimensions (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 ($\mathrm{\Delta }q=0.02{\text{Å}}^{-1}$) and energy ($\mathrm{\Delta }E=45$ meV) resolved setup is instrumental in delivering the experimental verification of quenched 2D EEL spectra on freestanding graphene at momentum transfers $q$ below $0.06{\text{Å}}^{-1}$. We retrieve the intrinsic uniform dielectric response of graphene from measured spectra by quantifying the kinematic suppression.

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• 2-dimensional systems
• Graphene
• Electron energy loss spectroscopy