Showing papers in "Nuclear Tracks and Radiation Measurements in 1985"

TL;DR: In this paper, the reduction in fission-track density in terms of a series of fanning lines on an Arrhenius plot has been interpreted in a range of activation energies corresponding to different degrees of annealing, with activation energies varying by a factor of 2 or 3 from complete retention to total erasure.

TL;DR: In this paper, wind-blown sand from Arago cave at Tautavel and beach sand from Terra Amata at Nice are studied for the dating by a quartz large grain technique using electron spin resonance (ESR).

TL;DR: The stability behavior of fission tracks in zircon under natural annealing conditions has been studied in this article, where fission track ages between 158 and 327 Myr were found.

TL;DR: In this article, it was shown that tunnelling radiative recombination occurs in labradorite and can explain anomalous fading in feldspars, and this afterglow was not detected earlier.

TL;DR: A TL dating program has been carried out on 42 sediments from NW Europe as discussed by the authors, where accumulated doses (ADs) have been measured by the natural regeneration method applied to ultraviolet emissions from fine-grain fractions.

TL;DR: In this article, the authors used thermoluminescence (TL) and electron spin resonance (ESR) to identify the defects responsible for the 100°C TL peak.

TL;DR: A review of the application of thermoluminescence (TL) methods for dating sediments is presented in this article, with a brief description of the philosophy of this application, various methods currently in vogue for estimating the accumulated radiation dose in sediments are described.

TL;DR: In this article, the authors proposed a method that may enable partially bleached sediments to be dated by determining the correct residual value to be used with the build-up curve.

TL;DR: Tooth enamel, consisting of hydroxyapatite, is a very useful natural material for ESR dating as mentioned in this paper, it occurs widely in archeological and geological deposits, has a low internal U content, and a long lifetime for trapped electrons.

TL;DR: In this article, the thermoluminescence of potassium feldspars (microcline) was studied and the glow curves showed six overlapping peaks with Tm values 95, 128, 223, 299, 384 and 470°C respectively when 2.5°C s−1 heating rate was used.

TL;DR: In this article, the authors used different mineral fractions obtained by heavy liquid separation for TL dating, and used all grain sizes up to several mm and developed methods for taking into account the beta dose contribution from inherent potassium in feldspar grains.

TL;DR: The results show that some workers have serious problems in achieving accurate age determinations and emphasize the need to calibrate experimental techniques and counting procedures against age standards before unknown ages are determined.

TL;DR: In this article, the authors report on detailed measurements of emission spectra recorded during TL and show that calcite samples have a yellowish hue attributed to Mn impurities whereas the purer CaCO3 crystals of Iceland Spar are colourless.

TL;DR: In this article, anomalous fading as a function of TL wavelength was investigated and it occurred equally at all wavelengths (300-650 nm) and irradiated zircons at elevated temperatures, however, was found to accelerate the fading rate and remove the fading component without thermally draining the stable component.

TL;DR: In this article, a semi-analytical solution of an equation describing the production and shortening of fission tracks in apatite suggests that certain thermal histories have unique length-distribution signatures.

TL;DR: In this article, experimental and/or theoretical estimates concerning attenuation within the sample of beta and gamma radiation from the soil, the gamma dose due to its own radioactivity, and the soil gamma dose in the proximity of boundaries between regions of differing radioactivity are presented.

TL;DR: In this article, the best ways of obtaining measurement reproducibility and avoiding interference from signals induced by irradiation and sample preparation were made of the ESR signals observed in speleothems collected from different geographical areas.

TL;DR: In this article, the ESR dating method for marine shells is compared with the independent U-series technique for determining the accumulated dose of each shell and the annual dose of the shell.

TL;DR: In this article, the authors compared the performance of the Corning 5-58 and Schott UG-11 filters for fine grain loess samples and found that the Schott filter produces greater enhancement of the lower temperature component of the natural TL, around 230°C.

TL;DR: A gas flow multicounter system developed at Riso National Laboratory for low-level beta counting applications was adopted for measuring potassium in feldspars extracted from archaeological and geological materials, in connection with TL dating work.

TL;DR: In this article, the radiation response of different gamma-induced ESR lines for calcite with variable low clay content and for chemically pure calcite was studied and the effect of these parameters on the age determination was discussed.

TL;DR: In this paper, the mechanism of uranium uptake on a geologically well-classified mammoth tooth was investigated and several models as described in the literature to overcome this effect were applied to overcome the effect.

TL;DR: Galbraith and Laslett as mentioned in this paper expressed many of the same statistical ideas at the 1984 Fission-Track Dating Workshop, and there was general agreement on the fundamental ideas and their justification and mathematical details.

TL;DR: In this article, confined track lengths have been used to monitor the annealing behaviour of fission tracks in Durango apatite and in two natural sphene samples subjected to laboratory anneal treatment.

TL;DR: In this article, the thermoluminescence spectra of plagioclase feldspars of varying Na and Ca proportions were obtained using a Fourier transform spectrometer developed in our laboratory for this purpose.

TL;DR: In this paper, the effects of experimental conditions (such as microwave power, modulation amplitude, ESR cavity temperature, detector phase and thermal pretreatment) on the ESR spectra are studied.

TL;DR: A microcomputer controlled scanning stage has been developed which greatly facilitates track counting as mentioned in this paper, which has been designed specifically for the external detector method of fission-track dating, although the basic hardware could be used for a variety of different scanning requirements.

TL;DR: In this article, it was shown that humic acid-doped calcite exhibits an ESR signal at g = 2.0043, with a line width of about 0.6 mT, that appears to be very radiosensitive.

TL;DR: In this article, a computer program (FTD-SIM) faithfully simulates the fissioning of 238U with time and 235U with neutron dose, and the simulation is based on first principles of physics.