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Measurement of 234U/238U in IRMM184 uranium standard using the Isotopx ATONA and Zeptona Faraday detector systems
Zenon Palacz, Shaun Yardley, Matt Hockley, Steve Guilfoyle Introduction High precision determination of 234U / 238U is important in many geological research applications. The typically low abundance of 234U (234U / 238U = 0.000053196 in IRMM184) in these applications has necessitated the use of ion counters for this isotope, while the much larger 238U must…
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Introducing SIRIX
The new standard in high performance IRMS Why SIRIX? Solving isotope ratio puzzles one step at a time Here at Isotopx we have a proud history in providing isotope ratio solutions. We consider ourselves to be the innovators in the industry, proven by our unique ATONA® and ZEPTONA technologies. By leveraging our technologies and platforms…
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U-Pb TIMS Geochronology using ATONA® Amplifiers
Dawid Szymanowski & Blair Schoene Department of Geosciences, Princeton University; dszymanowski@princeton.edu; bschoene@princeton.edu V11D-0124 Key Points ATONA [aA (10-18 A) to nA (10-9 A)] is a new Faraday cup signal amplifying technology for Isotopx Phoenix thermal ionisation mass spectrometers (TIMS) Main advantages for TIMS U–Pb geochronology (compared to conventional ion counting with peak-hopping): Better precision and…
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High precision isotope ratio measurements of Sr and Nd at the nanogram level using the Phoenix TIMS with next generation Faraday detectors
Zenon Palacz What are the parameters required for high precision measurements of small samples? (on Faraday collectors) High Sensitivity Instrument sensitivity Use of activators Low noise Close to theoretical Johnson noise Baseline stability Gain stability between detectors Required for static analyses Multidynamic measurements: Eliminates gain and efficiencies But can it be used on small samples?…
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Measurement of 2ng Nd (NdO+) using Xact Faraday collectors on a Phoenix TIMS equipped with 1e11 Ω and 1T Ω resistors.
Zenon Palacz, Davydd Wanless, Ian Turner & Tony Jones. Isotopx Ltd. UK Introduction We have shown that very small ion beams of Nd+ (5 to 50mv) can be measured accurately and precisely using the Phoenix TIMS equipped with either 1e11 Ω or 1T Ω resistors1 . For small sample sizes measurement of Nd as Nd+…
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Neodymium isotope ratio analysis using the Phoenix TIMS
Introduction Neodymium together with strontium isotope ratio measurements are the benchmark analyses that define the ultimate precision and accuracy of isotope ratio measurements that Thermal Ionization mass spectrometers are capable of. The mass fractionation which occurs during thermal ionization can be compensated for using the exponential mass fractionation law. This can lead to single analysis…
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2ppm reproducibility of 87Sr/86Sr achieved using the Phoenix TIMS
Introduction Very high precision Strontium isotope ratio measurements are particularly important in some geochronological applications. For example, variations as small as 0.00001 in 87Sr/86Sr are significant in high resolution dating of marine carbonates. (e.g. McArthur JM, Howarth RJ, Bailey TR. 2001.). In order to test the capabilities of the Phoenix Thermal Ionisation Mass Spectrometer to…
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87Sr/86Sr analysis of < 10ng NBS 987 on Phoenix TIMS
Introduction High sensitivity Sr isotope ratio measurements using TIMS can be used to evaluate sub millimetre isotope variations in zoned minerals and fluid inclusions. Sample sizes of a few nanograms of Sr are generated and so “every ion counts” to get a precise measurement. In this preliminary study a Phoenix TIMS was used to analyse…
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High precision Os isotope ratio measurements using Phoenix X62 TIMS
Introduction The study of Osmium isotopes is an important tool in geochemistry and cosmochemistry (e.g. Shirey and Walker 1998, Brandon et al. 2006, Ravizza and Turekian 1992). Side box 1 provides background on the two Os isotope systems of interest. Whilst 187Os/188Os ratios can vary by several percent, the variation in 186Os/188Os is far smaller…
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Multidynamic measurement of small Neodymium (Nd+) ion signals on Faradays using Xact amplifiers with 1e11 Ω and 1e12 Ω (1T) resistors
Introduction Thermal Ionization Mass Spectrometry is an extremely sensitive detection technique. For Neodymium, measured as Nd+ , ion yields of 1 ion per 50 atoms loaded are typical for triple filament geometries on a Phoenix TIMS. This efficiency is of huge importance for applications where there is very little sample material e.g. garnet growth rims…
