Cross-section for ¹⁰Be Production of High Energy Fragmentation of Oxygen

Abstract

KNOWLEDGE of the spallation cross-section for the production of ¹⁰Be from oxygen is important for several astrophysical problems, especially when this nuclide is used to date meteorites and cosmic rays. Several years ago, when the first direct measurements of this cross-section were made^1–3 the values were found to be much lower than had been previously estimated. Those working in cosmic ray physics have generally accepted the new values, and have modified their ideas accordingly. On the other hand, those doing meteorite studies have more often tended to retain the old values, perhaps because the inconsistencies involved in changing them were thought to be difficult to reconcile. A justification for this refusal to accept the measured values has been given by Goel⁴. His argument is based on indirect evidence obtained from comparative analysis of ¹⁰Be and ³H concentrations in stone meteorites. Although we do not feel it is necessary to belabour the correctness of the measured spectrometer values, it would perhaps be useful to point out the error in Goel's analysis which leads him to arrive at a conclusion in apparent contradiction with these data.