High-Current 14C Measurements on an HVE 1MV AMS System

Abstract

High radiocarbon sample throughput is an increasingly important requirement of accelerator mass spectrometry (AMS) systems, which in turn requires high source output. To accomplish this, HVE AMS systems use a model SO-110B ion source, which can run at outputs of more than 200 µA ¹²C. It is known that high source output may compromise precision. To quantify this effect, we have tested an HVE 1MV AMS system for the influence of medium (100 µA) and high (200 µA) source outputs on the precision. These early measurements indicate for a 200 µA ¹²C source output, equivalent to a ~1 kHz ¹⁴C count rate for Ox II samples, a ¹³C/¹²C precision of 1‰ and a ¹⁴C/¹²C precision of 3‰ can be obtained.

DOI: 10.2458/azu_js_rc.55.16052