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arXiv · 1512.01864

Nucleation, solvation and boiling of helium excimer clusters

Luis G. Mendoza Luna·Nagham M. Siltagh·Mark J. Watkins·Nelly Bonifaci·Frederic Aitken·Klaus von Haeften
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Abstract

Helium excimers generated by a corona discharge were investigated in the gas and normal liquid phases of helium as a function of temperature and pressure between 3.8 and 5.0 K and 0.2 and 5.6 bar. Intense fluorescence in the visible region showed the rotationally resolved $d^3\Sigma_u^+ \rightarrow b^3\Pi_g$ transition of He$_2^*$. With increasing pressure, the rotational lines merged into single features. The observed pressure dependence of linewidths, shapes and lineshifts established phases of coexistence and separation of excimer-helium mixtures, providing detailed insight into nucleation, solvation and boiling of He$_2^*$-He$_n$ clusters.

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Luis G. Mendoza Luna, Nagham M. Siltagh, Mark J. Watkins, Nelly Bonifaci, Frederic Aitken, Klaus von Haeften. 2015-12-07. Nucleation, solvation and boiling of helium excimer clusters. https://arxiv.org/abs/1512.01864

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