Abstract
The isotopic composition and concentration of He, Ne and Ar produced by cosmic rays were measured spectrometrically in bulk samples and in taenite and schreibersite phases of 4 iron meteorites. The 3He concentrations in taenite are lower than those in either schreibersite or bulk samples. This difference cannot be attributed solely to variations in chemical composition and is contradictory to observations of hydrogen diffusion in kamacite and taenite. The 4He, neon and argon concentrations in taenite fit the spallation systematics for iron meteorites well. Furthermore, calculations of the concentrations (based on the Rudstam spallation model) agree well with the observed data. Thus, we conclude that no fragmentation processes with anomalous cross sections occur in the production of neon from phosphorus.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
