Simultaneous ion-beam collection for precise measurement of nuclidic ion-current ratios in spark-source mass spectrometry.

Simultaneous ion-beam collection techniques make significant improvement possible in the precision of measurements when electrical ion-detection is used with the spark ion-source. The advantage of reference of specific ion-current signals only to those from desired regions of the mass spectrum is that reproducible measurements may be made on heterogeneous samples such as oxide-graphite pellets. For example, isotopic ratio measurements from separate samplings of an oxide (pelleted with graphite) are reproducible to better than +/-0.