High sensitivity S-option upgrade for an inductively coupled plasma mass spectrometer system

电感耦合等离子体（ICP）源与四极质量过滤器是最具成本效益的仪器测量同位素中等精度和高通量。结合激光烧蚀源，它被用来测定大量锆石颗粒的年代，达到中等精度。这些年代是了解古代地质事件和过程的有力工具。虽然等离子体产生接近100%的电离，但离子进入质量分析仪的高真空的传输效率很低，这限制了灵敏度。所要求的设备包括一个75升/秒的旋转泵，连接到离子采样接口，离子从等离子体的大气压传递到离子聚焦区域。通过降低该区域的压力，离子与其他分子碰撞和中和的可能性就会降低，估计灵敏度将提高3到6倍。这将极大地扩展仪器的能力，以准确分析相对年轻和高质量的锆石，以及用于测定陨石年代的低u相。改进后的年龄数据将有利于与我们合作的许多地质学家，以及正在确定与太阳系形成有关的事件的年代的学生。

The inductively coupled plasma (ICP) source with a quadrupole mass filter is the most cost effective instrument for measuring isotopes with moderate precision and high throughput. Combined with a laser ablation source, this is used for dating large numbers of zircon grains to moderate precision. These ages are a powerful tool for understanding ancient geologic events and processes. Although plasmas produce close to 100% ionization, the transmission efficiency of ions into the high vacuum of the mass analyzer is low, placing a limitation on sensitivity. The equipment requested consists of a 75 litre/sec rotary pump connected to the Ion Sampling Interface where ions pass from the atmospheric pressure of the plasma to the ion focusing region. By reducing the pressure in this region there is less probability of collision and neutralization of ions with other molecules, giving an estimated increase in sensitivity of a factor of 3 to 6. This will greatly extend the ability of the instrument to accurately analyze relatively young and high quality zircon as well as low-U phases used for dating meteorites. The improved age data will be of benefit to the many geologists with whom we collaborate as well as to students who are dating events associated with the formation of the solar system.