Association between temperature dependence of liquid 4He scattering law and the phenomena of the Bose condensation

Abstract

The He excitation spectrum at the phonon-maxon region of dispersion curve carried out by inelastic neutron scattering was studied to assess the relationship between phenomena of Bose condensation and unique type of the excitations of liquid He. Measurements were performed on the time-of-flight direct geometry DIN-2PI spectrometer. Initial neutron energy was set about 2 meV and multi-detectors system at angle scattering range 6.3-71° allowed the coverage of Q range from 0.2 up to 1.15 angstroms-1 in one measurements. The Q-dependent resolution widths varied between 0.05 and 0.1 meV.