Three-body recombination at thermal energies

智力价值该项目的目标是一个机会，以最新的发展为基础，对热能下的三体复合问题提出一种全新的方法。将特别注意发展理论和计算技术，以研究和控制煤炭燃烧过程中发生的基本过程，以及在较长时间范围内发生的简单碳氢化合物。三个物体碰撞在热和超冷温度下发生的过程中发挥重要作用。将发展计算热能下三体碰撞速率系数的新的可靠的理论和数值技术，并将其应用于几个对基础科学(原始的氢的三体复合)和应用科学(煤燃烧)重要的过程。这个项目将主要处理中性原子在热能和低能(化学反应)下的三体碰撞。然而，带电粒子的进一步发展预计将在稍后阶段进行。本项目的主要内容如下：(1)热能下三种体率系数测定技术的发展。主要致力于三体复合反应A+B+C AB(v，j)+C，其思想是发展精确的(主要是数值的)和理论的(用最少的数值计算)技术，并在相对简单的系统上进行测试。(2)方法：(A)三体薛定谔方程的数值解，采用超球坐标和最近发展的一种有效的本征通道R矩阵的慢变量离散化技术：(B)三体复合的简单的理论两步模型：A+Bab*，AB*+C AB(v，j)+C+能量。另一种坐标，埃卡特坐标，将被用来求解三体薛定谔方程。埃卡特坐标结合了公认的替代坐标的某些优点：超球坐标和雅可比坐标。广泛影响本项目研究的成功完成应该会产生一些更广泛的影响：(1)所开发方法(在物理、化学、天体物理、等离子体物理、燃烧化学和燃烧控制方面)的跨学科重要性；(2)培养有才华的研究生，他们将拥有解决该学科领域最新问题所需的工具。

Intellectual MeritThe project is targeting an opportunity to build on the very recent development of a qualitatively new approach to the problem of three body recombination at thermal energies. Special attention will be made to develop theoretical and computational techniques to study and control elementary processes taking place during combustion of coal and, in a longer time frame, simple hydrocarbons.Three body collisions play an important role in processes occurring at thermal and ultracold temperatures. New robust theoretical and numerical techniques for calculation of rate coefficients for three body collisions at thermal energies will be developed and applied to several processes important for fundamental science (primordial three body recombination of hydrogen) and applied science (coal combustion). This project will primarily deal with three body collisions of neutral atoms at thermal and low energies (chemical reactions). However, a further development for charged particles is envisaged at a later stage. Principal points of the present project are the following: (1) Development of techniques for determination of three body rate coefficients at thermal energies. The main effort will be made on the reaction of three body recombination, A+B+C AB(v,j)+C. The idea is to develop exact (mostly numerical) and theoretical (with minimum numerical calculations) techniques and test them on relatively simple systems. (2) Methods: (a) Numerical solution of the three body Schrödinger equation, using hyperspherical coordinates with a recently developed efficient technique for the eigenchannel R matrix with slow variable discretization; (b) A simple theoretical two step model for three body recombination: A+BAB*, AB*+C AB (v,j)+C + energy. Another type of coordinates, Eckart coordinates, will be employed to solve the three body Schrödinger equation. The Eckart coordinates combine certain advantages of the well established alternatives: hyperspherical and Jacobi coordinates.Broader ImpactsA number of broader impacts should emerge from the successful completion of the research in this project: (1) the cross disciplinary importance of the developed methods (in physics, chemistry, astrophysics, plasma physics, combustion chemistry, and in the control of combustion); (2) the training of talented graduate students who will have the tools needed to tackle state-of-the-art problems in this subject area.