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arXiv · 1512.07742

First sound velocity in liquid $^{4}$He

O. I. Hryhorchak
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Abstract

Based on the many-boson system structure factor, which takes into account three- and four-particle direct correlations, there was found the first sound velocity temperature behaviour in liquid $^4$He in the post-RPA approximation. The expression received for the sound velocity matches with the well-known results in both low and high temperature limits. The results of this paper can be used to analyze the contributions of three- and four-particle correlations into thermodynamic and structural features of liquid $^4$He.

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O. I. Hryhorchak. 2015-12-24. First sound velocity in liquid $^{4}$He. https://doi.org/10.5488/cmp.18.43001

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