Forensic comparison of shotshell-pellet specimens by instrumental neutron activation analysis

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6869868

Jourdan, T H

The very rapid INAA method, developed by Guinn and Purcell, works well for the determination of Sb, Ag, and Cu in shotshell pellets. Arsenic is also of interest to this study because it is added during the production of shotshell pellets to increase sphericity during pellet formation in the shot tower. Unfortunately, the one arsenic (n,..gamma..), product, 26.32 h /sup 76/As, is not susceptible to analysis via the rapid method. In the present study, a method involving a one-hour irradiation in the UCl TRIGA Mark 1 nuclear reactor was found to be effective in the determination of arsenic content in lead samples. This method also facilitates a second determination of antimony and copper levels via /sup 122/Sb and /sup 64/Cu activities. Several methods for the resolution of the 559-keV /sup 76/As/564-keV /sup 122/Sb photopeak doublet were evaluated. Also, two new gamma attenuation models, for disc and spherical lead samples, were developed. These models respond to the recognition that the gamma rays employed to assay the concentrations of the various elements are themselves attenuated within the sample - a lead matrix. After demonstrating that ammunition from different manufacturers, as well as inter-lot variances within a single manufacturer's ammunition, can readily be differentiated, this study also led to a statistically rigorous assignment of the probability of common origin of shotshell-pellet, or bullet-lead specimens, of analytically indistinguishable or nearly indistinguishable compositions. Additionally, the dissertation contains an Appendix detailing the development of the shotgun and its ammunition for those who are not very familiar with forensic ballistics.

• Research Organization: California Univ., Irvine (USA)
• OSTI ID: 6869868
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101* -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
ACTIVATION ANALYSIS
AMMUNITION
ANTIMONY
ANTIMONY 122
ANTIMONY ISOTOPES
ARSENIC
ARSENIC 76
ARSENIC ISOTOPES
BARYON REACTIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CHEMICAL ANALYSIS
COPPER
COPPER 64
COPPER ISOTOPES
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
HADRON REACTIONS
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LEAD
METALS
MINUTES LIVING RADIOISOTOPES
NEUTRON REACTIONS
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
ODD-ODD NUCLEI
RADIOISOTOPES
SEMIMETALS
SILVER
TRANSITION ELEMENTS