Theory of Atomic Collisions

这项研究将探索强相互作用的原子系统，以开发实用的计算方案来处理它们。有五个项目需要承担：(1)。强相互作用原子和离子的微扰系列。为强相互作用系统开发的新摄动系列将正式扩展到处理电离，并应用于计算高电离原子与低Z目标相互作用的截面。这项工作与QED的一些联系最近被发现，预计它们将进一步探索。2. 新时变分原理。一个新的时变分原理，类似于时变问题的Schwinger原理，将应用于第一部分的一些问题。变分公式的优点是能够推导出用于高电离系统的强势玻恩计算的扭曲势的高阶近似。3. 超球面的扩张。先前发展的超球面膨胀将应用于氢离子在氘上的散射，作为对“无平移因子”理论的检验。我们将特别注意电子转移反应。剩下的就是使用计算的波函数和势曲线进行实际的耦合通道计算。4. 二次电子能谱中的鞍点效应。关于二次电子能谱中鞍点效应的研究工作将继续进行。将开发包含旋转效应的电子传播子的新近似，并使用新传播子计算最终态的近似波函数。主要的困难是多重积分的数值计算，但这似乎很容易处理。这与内布拉斯加州和田纳西州的实验工作有密切的联系。阿布拉莫夫模型中的对准与取向。对准和方向参数是一个非常敏感的测试碰撞近似。已经开发了Abromov模型来计算由低速电子捕获形成的状态的这些参数。该模型将应用于现有实验并进行验证。希望是刺激进一步的测量。与橡树岭、堪萨斯州立大学和其他高电荷离子源（如康奈尔大学）的实验小组密切合作。

This research will probe strongly interacting atomic systems to develop practical computational schemes for treating them. There are five projects to be undertaken: (1.) Perturbation Series of Strongly Interacting Atoms and Ions. The new perturbation series developed for strongly interacting systems will be formally extended to treat ionization and applied to compute cross sections for the interaction of highly ionized atoms with low Z targets. Some connections of this work and QED have recently been discovered and it is expected they will be explored further. 2. New Time Dependent Variational Principle. A new time dependent variational principle akin to the Schwinger principle for time independent problems will be applied to some of the problems of part 1. The advantage of the variational formulation is to be able to derive higher order approxi- mations to the distorting potential used in the strong potential Born calculations for highly ionized systems. 3. Hyperspherical Expansions. The hyperspherical expansion developed earlier will be applied to the scattering of H+ on deuterium as a test of the "translation factor free" theory. Particular attention will be paid to electron transfer reactions. All that remains is the actual coupled channel calculation using the computed wave functions and potential curves. 4. Saddle Point Effects In Secondary Electron Spectra. Work on saddle point effects in secondary electron spectra will be continued. New approximations to the electron propagator will be developed which contain rotational effects and the new propagator will be used to compute an approximate wave function for the final state. The primary difficulty is the numerical evaluation of the multiple integrals but this seems quite tractable. There are close connections with experimental work at Nebraska and Tennessee. 5. Alignment and Orientation in the Abramov Model. Alignment and orientation parameters are a very sensitive test of collisional approximations. The Abromov model has been developed to compute these parameters for states formed by electron capture at low velocities. The model will be applied and tested against existing experiment. The hope is to stimulate further measurements. There is close co-operation with the experimental groups at Oak Ridge, Kansas State, and other highly charged ion sources such as that at Cornell.