気態および液態ヘリウムのクラスター理論III
運動量空間における凝縮
1960 年 8 巻 1 号 p. 8-48
詳細
1960 年 8 巻 1 号 p. 8-48
A formula is derived which expresses, in terms of the “cluster integrals”, the one-particle distribution function nΡ in momentum space for a system (in thermal equilibrium) composed of N interacting particles in a volume V. And some theorems are proved which are useful for obtaining nΡ in the limit N→∞ with v=V/N fixed.
Then the theorems are applied to the perfect Booe gas and the gaseous and liquid helium in order to investigate the “ordering in momentum space” for these system. Using the results obtained in the previous papers I and II, it is shown that this ordering does not appear in the gaseous He or in the liquid He I, but does in the liquid He II.
