Laser Induced Nuclear Orientation

Abstract

There is a growing awareness that the techniques of laser spectroscopy can be brought to bear on nuclear physics problems in a variety of ways.[1] Laser induced nuclear orientation [2,3] is one such example of the intersection of laser spectroscopy and nuclear spectroscopy. In this technique the angular momentum transferred to a resonantly absorbing atomic (or molecular) transition by polarized laser radiation can orient the atomic nuclei along a given axis. If the nuclei are unstable, the angular distribution of the subsequent nuclear radiation (gamma, beta, fission fragments, etc.) will be anisotropic. This spatial anisotropy can be a sensitive probe for resolving hyperfine splittings and other nuclear structure effects, especially when coupled with laser saturation or atomic-molecular beam techniques. Another important aspect is the ability to use laser photons to control gamma or other nuclear radiation. The new physics to be studied includes precision measurements of isomer shifts and excited state nuclear moments. The technique can also be used to produce polarized targets and beams, for nuclear isomer separation, weak interaction studies, and possibly to produce narrow band gamma radiation. Some of these potential applications are described elsewhere.[2,3] The present discussion will be restricted to three topics: describing the technique of laser induced nuclear orientation presenting preliminary observations of the effect in 24mNa proposing a technique for producing tunable, narrowband gamma radiation