Structure Factor of Liquid Helium-4: the Apparent Discrepancy Between Theory and Experiment

The structure factor $S\left(k\right)\mathrm{}$ of liquid helium-4 obtained by scattering experiment shows a substantial deviation from the Feynman prediction for small $k$ values. By attributing this discrepancy to the existence of a usually overlooked short-range structure in gaseous helium, the data of Gordon, Shaw, and Daunt are reanalyzed. The experimental $S\left(k\right)\mathrm{}$ now shows an improved agreement with the theoretical prediction. A further experimental verification is suggested.