Meteoritics & Planetary Science 46, Nr 2, 284–310 (2011) doi: 10.1111/j.1945-5100.2010.01154.x
Cosmic-ray exposure history of the Norton County enstatite achondrite G. F. HERZOG1*, Achim ALBRECHT1à, Peixue MA1§, David FINK2, Jeffrey KLEIN3, Roy MIDDLETON3 , Donald D. BOGARD4, L. E. NYQUIST4, C.-Y. SHIH5, D. H. GARRISON5, Young REESE6, J. MASARIK7, R. C. REEDY8, G. RUGEL9, T. FAESTERMANN9, and G. KORSCHINEK9 1
Department of Chemistry and Chemical Biology, Rutgers University, 610 Taylor Road, Piscataway, New Jersey 08854–8066, USA à Present address: National Radioactive Waste Management Agency, Direction Scientifique – Service Transferts, Parc de la Croix Blanche 1 ⁄ 7, rue Jean-Monnet 92298, Chaˆtenay-Malabry Cedex, France § Present address: Division of Consolidated Laboratory Services, 600 North 5th Street, Richmond, Virginia 23219, USA 2 Institute for Environmental Research, Australian Nuclear Science and Technology Organisation, PMB 1, Sydney, New South Wales 2234, Australia 3 Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA 4 Johnson Space Center, Houston, Texas 77058, USA 5 ESCG, Jacobs-Sverdrup, Houston, Texas 77058, USA 6 Mail Code JE-23, ESCG ⁄ Muniz Engineering, Houston, Texas 77058, USA 7 Nuclear Physics Department, Comenius University, 842 15 Bratislava, Slovakia 8 Planetary Science Institute, Los Alamos, New Mexico 87544, USA 9 Fakulta¨t fu¨r Physik, TU-Mu¨nchen, 85748 Garching, Germany Deceased. * Corresponding author. E-mail:
[email protected] (Received 22 December 2009; revision accepted 04 November 2010)
Abstract–We report measurements of cosmogenic nuclides in up to 11 bulk samples from various depths in Norton County. The activities of 36Cl, 41Ca, 26Al, and 10Be were measured by accelerator mass spectrometry; the concentrations of the stable isotopes of He, Ne, Ar, and Sm were measured by electron and thermal ionization mass spectrometry, respectively. Production rates for the nuclides were modeled using the LAHET and the Monte Carlo N-Particle codes. Assuming a one-stage irradiation of a meteoroid with a preatmospheric radius of approximately 50 cm, the model satisfactorily reproduces the depth profiles of 10Be, 26Al, and 53Mn (
