[en] A simple and reliable furnace design capable of producing temperatures of up to 2800 deg. C is presented. The furnace has been specifically designed for the rapid and reliable production of graphite targets for ¹⁴C dating purposes but may be used in a variety of applications requiring high temperatures under vacuum conditions

[en] The Institute of Nuclear Sciences accelerator mass spectrometry system has been used to determine the ages of a selection of spicules from crown of thorns starfish, collected at the Great Barrier Reef, Queensland. The measurements constitute a pilot study to determine the feasibility of using the technique to establish whether or not there is a periodicity in the invasion of The Great Barrier Reef by Crown of Thorns starfish

[en] Values of the spin rotation parameter, β, are measured in the reaction π⁺p → K⁺Σ⁺ at incident pion momenta of 1.69 and 1.88 GeV/c. (author)

[en] An energy dependent partial wave analysis of the reaction π⁺ p → K⁺ Σ⁺ has been carried out between threshold and 2.35 GeV centre of mass energy using recently published, high statistical precision data. A single solution giving a satisfactory fit to the data has been found. In the region below 2 GeV the resonant features of the solution are compared with the QCD based model of Koniuk and Isgur. Above 2 GeV the states listed in the Particle Data group tables with two or more stars are observed but none of the dubious one star states is confirmed Significant SU(3) breaking is observed in some amplitudes. (author)

[en] Differential cross sections and polarisations in the reaction π⁺p→K⁺μ⁺ have been measured using the Rutherford Multiparticle Spectrometer at NIMROD. Data are presented at 26 momentum points at approximately 50 MeV/c intervals in the range 1.282 to 2.473 GeV/c with an order of magnitude more events than previous experiments. Legendre polynomial expansion coefficients have also been determined. (author)

[en] New high statistics measurements of π⁺p elastic scattering differential cross-sections are presented at 30 momentum points between 1.282 and 2.472 GeV/c, covering most of the angular distribution outside the forward diffractive peak. These data show significant disagreements at some momenta with previous high statistics experiments and with current partial wave analyses. (author)

[en] A technique to make measurements of δ¹³C in atmospheric methane (δ¹³CH₄) to a precision of 0.02 per mille (1 sigma) is presented. Measurements of the mixing ratio and δ¹³CH₄ from Baring Head, New Zealand and Scott Base, Antarctica are reviewed for the period 1989 to 1998. The data show persistent but irregular seasonal cycles in δ¹³CH₄ ranging from 0.1-0.3 per mille superimposed on an increasing secular trend of about 0.04 per mille.year^-1 . In 1990/91 a 0.2 per mille positive anomaly appeared in this trend. The causes of the anomaly remain unresolved but, during 1992 when it disappeared, the decrease in δ¹³C was approximately coincident with a decrease in growth rate consistent with a decrease in biomass burning sources, which are relatively enriched in ¹³CH₄. δ¹³CH₄ data are also reported from large clean air samples collected every 2.5 deg. to 5 deg. of latitude on four voyages across the Pacific between New Zealand and the West Coast of the USA in 1996 and 1997. These data show that the inter-hemispheric gradient for δ¹³CH₄ was highly dependent on season, and varied from less than 0.1 per mille in June 1996 to more than 0.5 per mille in November 1996 with an estimated annual mean of 0.2-0.3 per mille. (author)

[en] A technique to make measurements of δ¹³C in atmospheric methane (δ¹³CH₄) to a precision of 0.02 per mille (1 sigma) is presented. Measurements of the mixing ratio and δ¹³CH₄ from Baring Head, New Zealand and Scott Base, Antarctica are reviewed for the period 1989 to 1998. The data show persistent but irregular seasonal cycles in δ¹³CH₄ ranging from 0.1-0.3 per mille superimposed on an increasing secular trend of about 0.04 per mille.year^-1 . In 1990/91 a 0.2 per mille positive anomaly appeared in this trend. The causes of the anomaly remain unresolved but, during 1992 when it disappeared, the decrease in δ¹³C was approximately coincident with a decrease in growth rate consistent with a decrease in biomass burning sources, which are relatively enriched in ¹³CH₄. δ¹³CH₄ data are also reported from large clean air samples collected every 2.5 deg. to 5 deg. of latitude on four voyages across the Pacific between New Zealand and the West Coast of the USA in 1996 and 1997. These data show that the inter-hemispheric gradient for δ¹³CH₄ was highly dependent on season, and varied from less than 0.1 per mille in June 1996 to more than 0.5 per mille in November 1996 with an estimated annual mean of 0.2-0.3 per mille. (author)

[en] The introduction of TAMS has exciting implications for radiocarbon dating but improved sample preparation methods are needed. This paper describes a promising method for the conversion of a few milligrams of wood or charcoal into graphite targets for use in a caesium sputter ion source. Targets containing a large proportion of G-type graphite produced large C^- currents, but those containing a high proportion of turbostatic Tn graphite were unsatisfactory; the type of graphite in the target is clearly of significance. (author)

[en] A review of recent computer model studies of the global atmospheric consequences of nuclear war is presented. The studies predict that sub-freezing surface temperatures and semi-darkness beneath regional-scale smoke and dust clouds are the most serious long-term atmospheric repercussions following a nuclear exchange. These studies and the subsequent predictions of global ecological disaster by some biologists have aroused considerable contention amongst scientists from many disciplines. Despite this contention, the predictions of the models reviewed here remain unrefuted. However, from the models so far published the severity of the predicted atmospheric effects and their temporal evolution, particularly in the Southern Hemisphere, cannot be accurately forecast