High-resolution (0.13 eV) photoemission measurements performed at low temperatures (≈ 20 K) show that a sharp feature (measured width ≃ 0.15 eV at full width at half maximum) exists at the Fermi edge in the electronic structures of U${\mathrm{Be}}_{13}$ and U${\mathrm{Pt}}_3$. In U${\mathrm{Be}}_{13}$ the feature shows some temperature dependence.

• Received 6 August 1984

DOI:https://doi.org/10.1103/PhysRevLett.53.2050