O01_P04

Status report of the in-situ ¹⁴C extraction line at HEKAL AMS laboratory

Buró B¹, Fülöp R², Jull A^1,3, Molnar M¹

¹INTERACT AMS Laboratory, Debrecen, Hungary, ²Australian Nuclear Science and Technology Organisation, Lucas Heights, Australia, ³Department of Geosciences, University of Arizona, Tucson, USA

In this study we presented a new cosmogenic in-situ ¹⁴C extraction line at the ICER laboratory, which is similar as the one published by Fülöp et al.(2019). These extraction system used the phase transformation of quartz to cristobalite on high temperature in order to quantitatively extract the carbon as CO₂. The system consists of three independent components. 1: used for remove the atmospheric and meteoric ¹⁴C, 2: offline high-temperature (1650 °C) oven  for extract and trapped the cosmogenic in-situ ¹⁴C from quartz, 3: CO₂ gas purification and mass measurement line. After the extraction and cleaning, the purified CO₂ sapmles are measured with compact ¹⁴C AMS system (Environ MICADAS) and the gas ion source interface. The extraction line allows for rapid sample throughput of about 6 samples per week. The  sample masses ranging between 4 and 7 g of clean quartz.

Purified quartz samples were sieved and used for analyse the fraction of  250 – 500 µm. The carbon yield from quartz samples are good and we have the expected values.

Our first tests were on the borehole CO₂ blank gas and Cronus-R standards. The blank level of the whole line is quite low. We get similar experiences and results as Fülöp et al. (2019).