Measuring 7Be, 10Be and 210Pb in rain

Very weakly acidified de-ionised water and ⁹Be carrier are added to the collector at the beginning of the sampling period, typically one month.
When necessary, more de-ionised water is added to compensate for evaporation thus avoiding dry sample being blown from the collector by wind.
The collected water is filtered and passed through an ion-exchange column to absorb the Be which is then eluted with 4M HCl.
Excess acid is evaporated, Be recovered as hydroxide and the ⁷Be measured by gamma spectrometry.
A sub-sample is taken for chemical yield determination and the remainder processed for ¹⁰Be analysis by AMS.
The residue from the filters is processed separately.
If required, ²¹⁰Pb can also be measured and an exchange service is available for ion-exchange columns and filters.

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