Electron and photon collision phenomena in atoms and molecules

在地球上层大气中，亚稳态原子的释放常常主宰着“北极光”，是什么机制导致了亚稳态原子的产生或消失？当x射线或其他高能辐射进入我们的身体时，释放的电子会发生什么？这些电子对DNA的伤害有多大？如何使用激光冷却和原子陷阱来获得工业等离子体中碰撞过程的数据，特别是那些涉及激发态原子的数据？如何产生像硫或氧原子这样的活性粒子束，并用于量化行星大气中发生的过程？像水这样的分子在受到电子轰击时是如何分解的？它们得到特定碎片的几率有多大？实验学家和理论家如何才能最好地合作，建立碰撞过程的精确模型？

What are the mechanisms responsible for producing or de-exciting the metastable atoms whose emissions often dominate the “Northern Lights” in earth’s upper atmosphere? What happens to the electrons which are released when X-rays or other high energy radiation enters our bodies? How damaging are these electrons to our DNA? How can laser cooling and atom traps be used to obtain data about collision processes in industrial plasmas, particularly those involving atoms in excited states? How can beams of reactive particles like sulphur or oxygen atoms be produced and used to quantify processes occurring in planetary atmospheres ? In what ways do molecules like water break up when bombarded with electrons and what are the chances of getting particular fragments when they do? How can experimentalists and theoreticians work together best to establish accurate models of collision processes? These are some of the questions that we will be seeking answers to during the next grant period. To help accomplish this we plan a range of sophisticated experiments involving beams of electrons, laser photons and a variety of targets. We will be using state-of-the-art techniques including laser cooling and trapping of atoms, unique metastable atom detection, and mass, optical and electron spectrometries. Many of the experiments are designed to provide accurate data for refinement of current theoretical ideas. Close collaboration will be maintained with other scientists doing related work in Canada and around the world. Not only are the research areas under consideration at the forefront of world research but the experiments are designed to encourage the involvement of students, both undergraduate and graduate . Some are motivated by demands for information by high-technology industry. In addition to their fundamental importance, the data obtained will have significance for atmospheric and planetary physics, the aurora, low temperature plasma physics, electrical discharges, radiation damage in biological materials, photonics and fusion energy generation.