Lithium-6 from Solar Flares

By introducing a hitherto ignored Li-6 producing process, due to accelerated He-3 reactions with He-4, we show that accelerated particle interactions in solar flares produce much more Li-6 than Li-7. By normalizing our calculations to gamma-ray data we demonstrate that the Li-6 produced in solar flares, combined with photospheric Li-7, can account for the recently determined solar wind lithium isotopic ratio, obtained from measurements in lunar soil, provided that the bulk of the flare produced lithium is evacuated by the solar wind. Further research in this area could provide unique information on a variety of problems, including solar atmospheric transport and mixing, solar convection and the lithium depletion issue, and solar wind and solar particle acceleration.Comment: latex 9 pages, 2 figures, ApJ Letters in pres

Lithium Isotope Analyses of Inorganic Constituents from the Murchison Meteorite

Aqueous processes were important modifiers of solid matter during the early stages of solar system history. Lithium isotopes are sensitive indicators of such solid-liquid interactions because 7Li passes preferentially into solution and 6Li remains behind in the solid phase. Lithium isotope ratios of inorganic phases in the Murchison meteorite reveal that the value for the whole rock is simply the average of individual components with widely different isotopic compositions. 7Li content increases from chondrules to phyllosilicate-rich matrices to carbonates, as would be expected from the relative duration each component has spent during aqueous alteration on the parent asteroid