THE AUSTRALIS MICROBEAM ION-SOURCE

The AUSTRALIS (AMS for Ultra Sensitive TRAce eLement and Isotopic Stud ies) system being developed at the HIAF laboratory is a microbeam AMS system designed for in situ microanalysis of geological, samples, The microbeam source was implemented by modifying a HICONEX source, result ing in a versatile source for microbeam as well as high intensity macr obeam operations. The source features a high magnification sample view ing system, enabling live observation of the sputtering process and vi sual tuning of the primary beam. Microbeam of Cs+ as small as 30 mu m in diameter has been obtained in the tests. The secondary ion extracti on system features a ''screen'' electrode that is used to correct the primary beam trajectory affected by the extraction field, in order to return it to the geometric center of the sample. The paper will descri be the source, and results of the test of the source and the injector system.