First results from the PRL accelerator mass spectrometer

Accelerator mass spectrometry is a highly sensitive technique developed nearly four decades ago primarily for the measurement of cosmogenic radionuclides with half-lives exceeding a few hundreds of years. Long-lived isotopes having low abundance are not detectable by radiometric counter and sensitivity of the commonly used mass spectrometer is low. Therefore, long-lived isotopes with low abundance were not detectable. Advantage of the above-mentioned technique is that nuclides in the ionic state achieve high energies and hence stripping of multiple electrons is possible. This is used to reduce the isobaric and molecular interference considerably, permitting identification and measurement of isotopes with very low natural abundance (10^-10 to 10^-16) such as ¹⁴C (half-life = 5730 yrs), ¹⁰Be (1.51 Myr) and ²⁶Al (0.705 Myr). A much reduced analysis time² and very small amount of sample are the additional advantages gained in the method, opening new avenues of research in earth sciences, viz. carbon sequestration, climate change, geo- and biosciences