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

对简单原子和分子的高分辨率测量计划将继续进行，特别是对氢分子和氦原子这两个电子系统的测量。实验方法包括基态和亚稳态物质的多光子激发。脉冲放大的连续波染料激光器被用来获得多光子激发所需的高功率，同时保持高分辨率。氢的离解能和电离势将以新的精度测定，氦的结构测量将得到改进。这些测量将为计算两个电子系统的基态量子电动力学效应提供第一个严格的测试。微波。光学双共振将被用来精确地测量高里德堡态之间的跃迁。这项研究的一个主要焦点将是氢中激发态与电离和解离连续性的相互作用，包括双激发态的影响。里德堡态的衰变将在有无外加电场的情况下进行研究。氢的光解离非常接近临界值，这方面的工作将继续进行，这将产生关于原子之间长距离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.