Determination of primordial and cosmogenic radioactivity in achondritic meteorites by low-level, gamma-ray spectrometry

• Main Author: Muntean, R.A.
• Language: unknown
• Published: 2020
• Subjects: 71 CLASSICAL AND QUANTUM MECHANICS; GENERAL PHYSICS; ACHONDRITES; CHEMICAL COMPOSITION; METEORITES; GAMMA SPECTROSCOPY; POTASSIUM; RADIOACTIVITY; THORIUM; URANIUM; ACTINIDES; ALKALI METALS; ELEMENTS; METALS; SPECTROSCOPY; STONE METEORITES; Allan Hills; Antarc*; Antarctica
• Online Access: http://www.osti.gov/servlets/purl/5485606; https://www.osti.gov/biblio/5485606; https://doi.org/10.2172/5485606

A high-sensitivity, low-background gamma-ray spectrometer containing two 23 cm by 13 cm thallium-activated, sodium iodide detectors was used to measure long-lived primordial and cosmogenic radioactivity in a suite of achondritic meteorites. Potassium, thorium, uranium, and /sup 26/Al abundances were established for sixteen brecciated eucrites, two unbrecciated eucrites, a nakhlite, a chassignite, and a unique meteorite from Antarctica by nondestructive counting techniques. In several cases, multiple samples of the same meteorite fall were examined. Concentrations ranged from 79.8 ppM to 1150 ppM for potassium, 55.6 ppb to 663 ppb for thorium, 18.1 ppb to 190 ppb for uranium, and 45.0 dpm/kg to 99.0 dpm/kg for /sup 26/Al. In addition, a /sup 137/Cs concentration of 264 dpm/kg was observed in the Allan Hills 77005,9 specimen.