  We present optical measurements of the transition metal dichalcogenide
PdTe$_{2}$. The reflectivity displays an unusual temperature and energy
dependence in the far-infrared, which we show can only be explained by a
collapse of the scattering rate at low temperature, resulting from the vicinity
of a van Hove singularity near the Fermi energy. An analysis of the optical
conductivity suggests that below 150 K a reduction in the available phase space
for scattering takes place, resulting in long-lived quasiparticle excitations.
We suggest that this reduction in phase space provides experimental evidence
for a van Hove singularity close to the Fermi level. Our data furthermore
indicates a very weak electron-phonon coupling. Combined this suggests that the
superconducting transition temperature is set by the density of states
associated with the van Hove singularity.
