Source obsidian rare earth patterns and obsidian artefact provenience

The rare earth distributions in obsidian source material examined. For seven sources from Turkey examined by instrumental neutron activation analysis (INAA) the rare earth patterns provide a unique signature for the assignment of provenience for archaeological finds. Considerable economy in INAA measurements may be achieved for obsidian artefact provenience assignment.Ce travail examine la répartition d'éléments de terre rare dans les matériaux de sources obsidiennes. Aux sept sources de la Turquie, examinées par l'analyse par activation neutronique (INAA), les échantillons de terre rare fournissent une empreinte unique, qui signale l'assignation en provenance des trouvailles archéologiques. Une économie considérable peut être atteinte avec 1 ' INAA pour indiquer l'assignation en provenance d'artefacts obsidiens.Yellin Joseph, Perlman Isadore. Source obsidian rare earth patterns and obsidian artefact provenience. In: Revue d'Archéométrie, n°1, 1981. Actes du XXe symposium international d'archéométrie Paris 26-29 mars 1980 Volume III. pp. 325-330

University of California Radiation Laboratory Report UCRL-9524

Figures 1 and 2 summarize total decay energies for the four radioactive series. The alpha-decay energy obtained by measuring the energy of the alpha particle leading to the ground state includes the energy of the recoil nucleus. The curve shown in figure 3 defines in broad outline the conditions and regions of alpha instability. A great deal more is to be learned from a more detailed examination of the region where alpha radioactivity is prominent. Of great value to the experimentalist is that he is able to predict alpha energies, and the agreement between predicted and measured values often serves as a criterion for isotopic assignment. A number of systems for correlating alpha decay energies have been employed, and that perhaps most widely used is illustrated in figure 4. Here the isotopes of each element on a mass number vs. energy plot are joined, resulting in a family of curves which over a wide region comprise a series of nearly parallel lines

Atomic Energy Commission Report AECD-3177

Abstract: "Photographic plates have been used to measure the energy of neutrons from the fission of 25. The spectrum as inferred from the ranges of 850 protons recoiling in the forward direction shows a very wide maximum at ~1.5 Mev with an exponentially decreasing high energy tail which extends beyond 7 Mev. The minimum energy neutrons recorded were ~700 kv. If the spectrum is extrapolated to zero, one finds that this average neutron energy is about 1.85 Mev. The stopping power of the plates was calibrated by the use of monochromatic neutrons from the Li-7(pn) Be-7 reaction and the d-d reaction.