Cryogenic microjet for exploration of superfluidity in highly supercooled molecular hydrogenR. E. Grisenti1, R. A. Costa Fraga1, N. Petridis1, R. Dörner1 and J. Deppe2
1 Institut für Kernphysik, J. W. Goethe Universität Max-von-Laue-Str. 1, 60438 Frankfurt (M), Germany
2 LaVision GmbH - Anna-Vandenhoeck-Ring 19, 37081 Göttingen, Germany
received 2 November 2005; accepted in final form 21 December 2005
published online 11 January 2006
We describe a new approach to producing a sample of supercooled molecular para-hydrogen (pH2) at temperatures down to , well below the predicted superfluid transition temperature for pH2. Unique features of the present scheme are 1) the suppression of both homogeneous and heterogeneous nucleation processes and 2) the possibility to control the liquid temperature in a wide range across the transition. As a first step we demonstrate the stable production in vacuum of continuous hydrogen filaments of macroscopic dimensions. This technique coupled to light scattering experiments will enable microscopic investigations of superfluidity in liquid para-hydrogen.
47.27.Wg - Jets.
39.10.+j - Atomic and molecular beam sources and techniques.
47.27.Te - Convection and heat transfer.
© EDP Sciences 2006