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SIRIUS – a 6 MV pelletron accelerator at ANSTO was delivered and installed in 2014–2015. After initial testing and commissioning phase we have now moved into routine operations. Quality assurance data from the past 2 years demonstrates the excellent performance and SIRIUS is now our preferred instrument for 10Be, 26Al and 36Cl analyses.

We present our first 14C in-situ results for calibration and system blanks from the recently completed Australian Nuclear Science and Technology Organisation (ANSTO) – University of Wollongong (UOW) in-situ 14C extraction system. System performance parameters and quality is evidenced by low 14C blanks and good reproducibility for multiple targets from different reference materials. The 14C extraction scheme exploits the high temperature phase transformation of quartz to cristobalite in order to quantitatively extract the carbon as CO2. The in-situ 14C extraction system comprises three independently operated and modular units that are used for initial in-vacuo removal of meteoric 14C, followed by offline high-temperature heating of quartz to release trapped cosmogenic in-situ 14C, and finally CO2 gas purification and mass measurement. The design allows for rapid sample throughput of about 6 samples per week with samples masses ranging between 0.5 and 4 g of clean quartz. Other features include single-pass catalytic oxidation using mixed copper (I,II) oxide as catalyst, use of UHV-compatible components and of vacuum annealed copper tubing. We present results for sets of purified quartz samples prepared from CRONUS-A, CRONUS-R and CRONUS-N inter-comparison materials, with final averages consistent with published values. Following extraction and cleaning, CO2 gas aliquots for some of the samples were analysed using the ETH Zurich CO2 gas ion source at the ETH MICADAS AMS facility in addition to CO2 being graphitised using the ANSTO laser-heated graphitisation micro-furnace and then analysed on ANSTO’s ANTARES AMS facility. System blanks using either CO2 or graphite ion-sources at both facilities are on the order of ∼1 × 104 atoms.

There is growing interest in geochronological applications of terrestrial in situ-produced cosmogenic nuclides, with the most commonly measured being 10Be and 26Al in quartz. To extract and then separate these radionuclides from quartz and prepare them in the oxide form suitable for accelerator mass spectrometry (AMS) requires extensive and careful laboratory processing. Here we discuss the suitability of a crushed, sieved and etched, sub-aerially exposed vein quartz specimen (CoQtz-N) to act as a reference material for chemical laboratory preparation and AMS measurements. Splits of CoQtz-N were distributed to eleven target preparation laboratories. The CoQtz-N 10Be targets were then measured at seven different AMS facilities and five of the preparation laboratories had their 26Al targets measured at four different AMS facilities. We show that CoQtz-N splits are sufficiently homogeneous with regard to nuclide concentrations, that it has been cleaned of any atmospheric derived (i.e. meteoric) 10Be and that it has low concentrations of the major elements that can interfere with Be and Al extraction chemistry and AMS measurements. We derive preliminary concentrations for 10Be and 26Al in CoQtz-N as 2.53 ± 0.09 × 106 at/g and 15.6 ± 1.6 × 106 at/g, respectively, at the 95% confidence limit.

We present initial results of in situ 14 C system blank and calibration sample measurements obtained using the in situ 14 C extraction scheme developed at the University of Cologne. The 14 C extraction scheme specifically exploits the phase transformation of quartz to cristobalite in order to quantitatively extract the carbon as CO 2 and follows a scheme that is different to that of existing extraction systems. Features are offline furnace extraction, single pass catalytic oxidation using mixed copper (I,II) oxide as catalyst, the use of UHV-compatible components and of vacuum annealed copper tubing. The design allows a relatively rapid sample throughput – two samples per day as opposed to the current 2 days per sample that can be done on other lines – and can accommodate samples ranging between 0.5 and 4 g of clean quartz. Following extraction and cleaning, the CO 2 gas is measured using the gas ion source of the MICADAS AMS facility at ETH Zurich. The extraction system yields low systems blanks (10 +16 / −10 × 10 3 atoms 14 C, ±1 σ ) and the initial results indicate that further improvements are achievable. Measurements of the CRONUS-A standard sample show a good reproducibility and results are consistent with published values. We also present the first in situ 14 C results for the CRONUS-R standard material.

Most laboratories prepare carbonates samples for radiocarbon analysis by acid decomposition in evacuated glass tubes and subsequent reduction of the evolved CO2 to graphite in self-made reduction manifolds. This process is time consuming and labor intensive. In this work, we have tested a new approach for the preparation of carbonate samples, where any high-vacuum system is avoided and helium is used as a carrier gas. The liberation of CO2 from carbonates with phosphoric acid is performed in a similar way as it is often done in stable isotope ratio mass spectrometry where CO2 is released with acid in septum sealed tube under helium atmosphere. The formed CO2 is later flushed in a helium flow by means of a double-walled needle mounted from the tubes to the zeolite trap of the automated graphitization equipment (AGE). It essentially replaces the elemental analyzer normally used for the combustion of organic samples. The process can be fully automated from sampling the released CO2 in the septum-sealed tubes with a commercially available auto-sampler to the graphitization with the automated graphitization. The new method yields in low sample blanks of about 50000 years. Results of processed reference materials (IAEA-C2, FIRI-C) are in agreement with their consensus values.

The new AMS facility at the University of Cologne (CologneAMS), Germany, was established in 2010 with the delivery of the HVE 6 MV Tandetron AMS, which will be used for 14C, 26Al, 36Cl, 41Ca, 129I, 239U and 244Pu analyses. Parallel to the AMS installation the radiocarbon group has started to set up and test sample preparation methods and instruments for different materials. We present first results of reference and standard materials that have been processed and graphitized in our lab and measured at the ETH and CologneAMS facilities. The graphitization blank and its influence on small samples sizes processed with an automated graphitization system have been determined. Work on isolation of individual organic compounds with a preparative gas chromatography system has been started. The focus of our future work will be on reducing process blank levels and sample sizes as well as on the application of compound-specific radiocarbon analyses in (paleo-) environmental research.