NEW TECHNOLOGY FOR IMPROVING HIGH MASS ION DETECTION

本申请的长期目标是双重的： 提供了一个清晰的理解的物理机制， 迄今为止， 提出的方法，并构建原型硬件， 可以设计商业化的大质量检测仪器， 制造的。 第一阶段研究的具体目标是探索 一种有前途的新技术，用于检测高质量离子， 不完全依赖于二次电子的动力学喷射 并且不使用过高的电压进行操作。 最近 使用后倍增极提高离子检测灵敏度的方法 元件，以实现电流放大。 本申请 解决了提高二次产量的可行性， 在离子碰撞倍增电极的负粒子，通过改变 倍增极表面。 通过提供经处理以降低表面的倍增电极， 功函数，可以有利地利用物理和 大分子结构中固有的电子性质 生物分子 提高负碎片离子的产率， 可能的光电发射或电子发射电子预期从 用铯-氧覆盖层处理的倍增极表面。 的 基于所提出的离子探测器的商业应用 技术不仅可以扩展到磁扇区和TOF 仪器，但四极也是如此。

The long term objectives of this application are twofold: to provide a clear understanding of the physical mechanisms governing the increases in detection sensitivity demonstrated to date by the proposed methodology and to construct prototype hardware from which commercial high mass detection instrumentation can be designed and manufactured. The specific aim of Phase I research is to explore a promising new technology for detecting high mass ions which does not depend exclusively on kinetic ejection of secondary electrons and does not use excessively high voltages for operation. Recent approaches for improving ion detection sensitivity use post-dynode elements to achieve current amplification. This application addresses the feasibility of improving the yield of secondary negative particles at the ion impacted dynode by altering the dynode surface. By providing a dynode treated to lower the surface work function, advantageous use can be made of the physical and electronic properties inherent in the structure of large biomolecules. Enhanced yields of negative fragment ions and possibly photoemissive or thermionic electrons are expected from dynode surfaces treated with an overlayer of cesium-oxygen. The commercial application for ion detectors based on the proposed techniques would extend not only to magnetic sector and TOF instruments, but quadrupoles as well.