Magnetic field evolution of critical end point in UGe2

New measurements on the ferromagnetic heavy-fermion superconductor UGe2 are reported. Thermal expansion measurements via strain gage allow us to locate precisely the critical end point (CEP) of the first order boundary between the large moment ferromagnetic phase FM2 (M0 = 1.5 μB) and the small moment phase FM1 (M0 = 0.9 μB). The field dependence of the CEP is compared with that of the paramagnetic-FM1 transition above the tricritical point.