Natural ortho-para conversion rate in liquid and gaseous hydrogen

@article{Milenko1997NaturalOC,
  title={Natural ortho-para conversion rate in liquid and gaseous hydrogen},
  author={Yu.Ya. Milenko and R. M. Sibileva and Mikhail A. Strzhemechny},
  journal={Journal of Low Temperature Physics},
  year={1997},
  volume={107},
  pages={77-92}
}
We measured natural ortho-para conversion rates within a wide region of hydrogen fluid states: at temperatures 17–32 K in the liquid and at temperatures 40–120 K in the gas for densities up to 0.09 g/cm3. The experimental data for the gas phase are interpreted within the framework of a theory, the basic distinction of which from Wigner’s approach is that we take into account the dependence of the closest distance in a collision of two orthomolecules on their velocity (i.e., temperature). Our… 

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