The isotopic compositions of noble gases in the solar wind show high enrichments of light isotopes. When corrected for mass fractionation all five noble gases there can be resolved in terms of the two primitive noble gas components that have been identified in planetary solids. Reasons are presented for assigning the fractionation to a solar process that selectively enriches lighter nuclei at t...

Low background miniaturized proportional counters as developed for the GALLEX solar neutrino experiment can be applied to the detection of radioactive noble gas nuclides at very low activities. We have developed an apparatus that allows the activity of trace amounts of isotopes of the four noble gases Ar, Kr, Xe and Rn to be measured. The technique includes contamination-free chromatographic pu...

5083 Meshik, A., Mabry, J, Hohenberg, C., Marrocchi, Y, Pravdivtseva, O., Burnett, D, Ollinger, C., Wiens, R., Reisenfeld, D., Allton, J., McNamara, K, Stansbery E, & Jurewicz A.(2007) Constraints on Neon and Argon isotopic fractionation in solar wind. Science

We report on the results of a systematic ab initio study of the Jones birefringence of noble gases, of furan homologues, and of monosubstituted benzenes, in the gas phase, with the aim of analyzing the behavior and the trends within a list of systems of varying size and complexity, and of identifying candidates for a combined experimental/theoretical study of the effect. We resort here to analy...

salts the autocatalysis is not very marked, and the results are fairly reproducible Silica and similar surfaces appear to be very variable: water has a marked, and often unpredictable, effect on them. The m atter is further complicated by the fact th a t water actually formed in the reaction seems to have a more marked effect than th a t added from without. Another phenomenon, probably dependin...

The chemical differences between deep- and shallow-mantle sources of oceanic basalts provide evidence that several distinct components coexist within the Earth's mantle. Most of these components have been identified as recycled in origin. However, the noble-gas signature is still a matter of debate and questions the preservation of primitive regions in the convective mantle. We show that a mode...

We study a novel method of quasi-phase-matching for third harmonic generation in a gas cell using the periodic modulation of the gas pressure and thus of the third order nonlinear coefficient in the axial direction created by an ultrasound wave. Using a comprehensive numerical model we describe the quasi-phase matched third harmonic generation of UV (at 266 nm) and VUV pulses (at 133 nm) by usi...

For several years, progress has been made in understanding surface melting as well as surface roughening of various crystals such as ice, lead, rare gases etc. A so-called quasi-liquid layer (QLL), caused by surface melting, is expected to influence the vapor growth mechanism of crystals at temperatures not far below their melting points. The effect of the self-diffusion coefficient D of a QLL ...