Le Journal de Physique Colloques

THEORETICAL ISSUES CONCERNING THE STABILITY OF ELECTRON SPIN-POLARIZED HYDROGEN

W. C. Stwalley, Yea-Hwang Uang, R. F. Ferrante, R. W. H. Webeler

Published Jul 1, 1980• 4 citations

Abstract

Hydrogen atoms with their electron spin polarized in a strong magnetic field ("spinaligned hydrogen" ; symbolized H+) should remain a metastable gaseous quantum fluid even at absolute zero. However, there are many possible ways of destroying this metastability. At high density ≥ 1021/cm3) Berlinsky et al. have suggested that a coherent spin-wave destruction mechanism prevents stability. At lower densities (high enough for Bose-Einstein condensation, however), gas phase and surface recombination mechanisms should be of primary concern. One critical question is essentially the explosion limit for H+., i.e. at what density will a single electronic spin flip event trigger massive recombination, heating and destruction of the sample (perhaps a good "detector" for highly forbidden processes) ? The second critical question is what events will trigger such explosions assuming one is above the limit ? We shall present our current understanding of these two critical questions (including high accuracy two-body collision calculations) and their implications in experimental design (e.g. field inhomogeneity effects, helium coating of surfaces, removal of deuterium impurities, etc.).

DOI: 10.1051/jphyscol:1980705

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