The notion of remote element synthesis has recently been modified to explain the presence of nucleogenetic isotopic anomalies and decay products of short-lived nuclides by injection of a small amount of exotic nucleogenetic material. Even with this modification, remote element synthesis seems inconsistent with the following observations: Evidence of coupled variations in the chemical and isotopic compositions of the source material for meteorites. Residual coupling of chemical and isotopic heterogeneities across planetary distances in the solar system today. The mass-fractionation relationship seen across isotopes of elements in the planetary system, in the solar wind, and in solar flares. Linkage of short-lived radioactivities with isotopic anomalies and with physical properties of their host grains, as expected for early condensate of fresh stellar debris. Temporal and spatial distributions of short-lived nuclides and their decay products. Mirror-image (+ and -) isotopic anomalies in meteorite grains that sum to 'normal' isotopic ratios, as expected of unmixed products of the same nuclear reactions that produced our bulk elements. The lack of supporting evidence for 'presolar' grains or nearby stars that injected exotic material into the early solar nebula.
O. Manuel, "Conceptual Problems with Remote Element Synthesis," Proceedings of the Indian Academy of Sciences, Earth and Planetary Sciences, vol. 109, pp. 195-203, Indian Academy of Sciences, Mar 2000.
The definitive version is available at http://dx.doi.org/10.1007/BF02719164
Keywords and Phrases
Chemical Composition; Isotopic Composition; Meteorite; Radionuclide; Solar System; Element Synthesis; Planets
International Standard Serial Number (ISSN)
Article - Journal
© 2000 Indian Academy of Sciences, All rights reserved.