Precise Multiphoton Spectroscopy of Small Molecules and Atomic Helium (Physics)

简单原子的高分辨测量程序 和分子将继续，特别是集中在 二、电子系统分子氢和原子氦。 的 实验方法涉及多光子激发， 基态和亚稳态物种。 一种脉冲放大的cw染料 激光用于获得多光子所需的高功率 激发，同时保持高分辨率。 解离 氢的能量和电离势将被确定， 一个新的精度，和改进的测量将作出的 氦的结构 这些测量将提供第一个 量子电动力学效应计算的严格检验 在两个电子系统的基态中。 Microwave.optical 双共振将用于精确测量跃迁 在高里德堡态之间。 这项研究的一个主要重点是 氢的激发态与电离和离解 连续性，包括双激发态的影响。 的 里德伯态的衰变将研究有和没有 外部电场。 工作将继续进行， 氢的光解离非常接近阈值，这产生 原子间长程相互作用的详细信息。

A program of high resolution measurements on simple atoms and molecules will be continued, concentrating especially on the two.electron systems molecular hydrogen and atomic helium. The experimental methods involve multiphoton excitation of both ground state and metastable species. A pulse.amplified cw dye laser is used to obtain the high powers required for multiphoton excitation while retaining high resolution. The dissociation energy and ionization potential of hydrogen will be determined to a new accuracy, and improved measurements will be made of the structure of helium. These measurements will provide the first stringent tests of calculations of quantum electrodynamic effects in the ground states of two.electron systems. Microwave.optical double resonance will be used to precisely measure transitions between high Rydberg states. A major focus on this research will be the interaction of excited states in hydrogen with the ionization and dissociation continua, including the effects of doubly excited states. The decay of Rydberg states will be studied both with and without external electric fields. Work will continue on the photodissociation of hydrogen very near threshold, which yields detailed information on long.range interactions between atoms.