Momentum Distribution of Quantum Liquids at Finite Temperature

We present results of a path integral Monte Carlo (PIMC) calculation of the momentum distribution of Ne and normal 4 He at low temperatures. In the range of temperatures analyzed, consequently exchanges can be disregarded and both systems are considered Boltzmann quantum liquids. Their quantum character is well reflected in their momentum distributions which show clear departures from the classical limit. The PIMC momentum distributions are sampled using a new and more efficient method that generalises the standard McMillan approach. Kinetic energies of both systems as a function of temperature and at a fixed density are also reported.