OPTOMECHANICAL EFFECTS ON H2O VAPOR AND THEIR ASTROPHYSICAL IMPLICATIONS

In search of an explanation for the peculiar [D]/[H] distribution in the solar system a mechanical effect of light on H2O vapor is investigated which combines great isotope selectivity with mechanical transport, viz. light-induced drift. Results of laboratory experiments are presented. They show that in the protosolar nebula this effect may have been an important mechanism for the relative enrichment of deuterium on the inner planets of our solar system. Gravitational redshift provides a direction for this mechanism. The effect of light pressure is found to be 2 orders of magnitude smaller.