Laser-induced nuclear orientation

Laser optical pumping experiments in sodium led to the discovery of three previously unrecognized effects: reduced saturation thresholds (compared to that expected in the absence of optical pumping); anomalous spectral structure; and extremely narrow features inside the natural linewidth. It was demonstrated that optical pumping using a single mode dye laser of a cell of sodium vapor with small traces ( 1 torr) of buffer gas can polarize the sodium nuclei over the entire Doppler profile. Complete polarization was achieved with laser intensities approx. 200 mW/sq cm with 1 torr of argon gas. These results are important for the preparation of polarized sources and targets for accelerator physics.