Development of a Mass Spectrometer for Re-Os Using Sputtering

这一奖项是为了支持华盛顿卡内基研究所地磁系的一个仪器开发项目。激光共振电离源质谱计正在研制中，用于用同位素稀释法测定天然样品中的Os同位素比值和Re、Os浓度。目前，Re和Os的激光电离发生在样品上方的原子云中，该原子云是由脉冲钽丝加热产生的。与脉冲激光的短持续时间相比，灯丝的热脉冲相对较慢，导致原子云过早耗尽，并限制了仪器的最终精度。该项目的目标是通过采用脉冲溅射枪来取代热源来改进离子源系统。

This award is for the support of an instrument development project at the Department of Terrestrial Magnetism of the Carnegie Institution of Washington. A laser resonance ionization source mass spectrometer is being developed for the purpose of measuring Os isotopic ratios and Re and Os concentrations in natural samples via the isotope dilution method. Currently, the laser ionization of Re and Os takes place in an atom cloud above the sample that is produced by pulsed tantalum filament heating. The relatively slow thermal pulse of the filament compared to the short duration of the pulsed laser causes premature depletion of the atom cloud and limits the ultimate accuracy of the instrument. The goal of this project is to improve the ion source system by incorporating a pulsed sputtering gun to replace the thermal source.