Thermal Expansion and Magnetorestriction of the Heavy-Fermion Compound UPd₂Al₃

We report on thermal expansion and magnetostriction of the new hexagonal heavy fermion magnetic superconductor UPd2Al3. Measurements were taken on monocrystalline samples between 0.1K and 20K in magnetic fields up to 4T. Both thermal expansion and magnetostriction are strongly anisotropic and are dominated by magnetic effects. In an applied magnetic field, the thermal expansion anomaly observed near T(c) seems to be of first order