* Astronomy

Title: Solar Cosmic Ray Produced Radionuclides in the Salem Meteorite
Authors: Evans, J. C., Reeves, J. H., & Reedy, R. C.

The Salem meteorite fell on May 13, 1981. The details of the fall and recovery were reported by Pugh. The sample was obtained for nondestructive counting at Battelle, Pacific Northwest Laboratories within 2 months of the time of fall. The recovered sample consisted of five fragments totalling 61.4 grams. Initial inspection of the fragments revealed a relatively thick fusion crust (3 mm). The existence of this thick fusion crust on a relatively small object was taken as evidence that the recovered specimen might be a primary object rather than part of a shower. Two small chips were taken for electron microprobe examination. The meteorite was tentatively classified as a type LL5 ordinary chondrite on the basis of chemical analysis information obtained (JC Laul , Battell e NW, private communication). The fragments were subjected to nondestructive multidimensional gamma-ray spectrometry. Counts were made on the largest fragment (22.7 g) separately and on a group of the other four fragments totalling 38.7 g. In addition, 17.6-9 and 22.7-9 fragments were counted individually on a high-efficiency, anticoincidence-shielded, intrinsic germanium diode. Mockups were prepared from each of the five fragments for calibration standards. A full description of the counting systems used and calibration methods routinely employed by our laboratory on new-fall meteorites is given by Evans et al..

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