Neutron-Scattering Determination of the Momentum Distribution and the Condensate Fraction in LiquidHe4

Abstract

The momentum distribution function, $n\left(\overrightarrow{\mathrm{p}}\right)$, is determined for liquid ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ at 1.00, 2.12, 2.27, and 4.27 K from new neutron inelastic-scattering measurements at large momentum transfers. An improved method for extracting the condensate fraction, $n_0$, from $n\left(\overrightarrow{\mathrm{p}}\right)$ is presented and used to obtain new values for $n_0$ at 1.00 and 2.12 K and a revised value at 1.1 K.