Beryllium-10 mass spectrometry with a cyclotron.

The Grenoble cyclotron has been used as a mass spectrometer to measure ratios of beryllium-10 to beryllium-9 of 10(-8), 10(-9), and 10(-10) in standardized beryllium oxide samples. Similar measurements can be used to determine cosmogenic beryllium-10 (half-life, 1.5 x 10(6) years) profiles in various geophysical reservoirs such as sea sediments and polar ice. This procedure can be used either to date such samples or to give information about geophysical and astrophysical phenomena that have influenced the beryllium-10 production rate in the past.