Identifying large chondrites using cosmogenic radionuclides
Abstract
We measured the concentrations of the cosmogenic radionuclides Be-10, Al-26, Cl-36 and Ca-41 in the metal and stone fractions of three large chondrite showers to determine their pre-atmospheric size. Large chondrites are characterized by substantial contributions of neutron-capture Ca-41 in the stone fraction (up to similar to 2 dpm/gCa), low radionuclide concentrations in the metal fraction and high Be-10(stone)/Be-10(metal) ratios. Based on the measured concentrations in comparison with calculated cosmogenic nuclide depth profiles, using a semi-empirical and a purely physical model, we conclude that these objects had pre-atmospheric radii ranging from similar to 80 cm to >3 m. We conclude that the semi-empirical model is more reliable for spallogenic production rates in large objects, while the purely physical model is more reliable for neutron-capture products. (C) 2009 Elsevier B.V. All rights reserved.
Published in:
Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms 268,7-8 (2010) 1185-1188;
Link to original published article:
http://dx.doi.org/10.1016/j.nimb.2009.10.129
Date of Version
4-1-2010
Recommended Citation
Welten, K. C.; Caffee, M. W.; Hillegonds, D. J.; Masarik, J.; and Nishiizumi, K., "Identifying large chondrites using cosmogenic radionuclides" (2010). Department of Physics and Astronomy Faculty Publications. Paper 1342.
https://docs.lib.purdue.edu/physics_articles/1342