Polarized gas targets

This review describes the development and present performance of nuclear polarized gas targets in nuclear or particle physics experiments. After a brief account of the various development steps, the design principles for the relevant light nucleon targets, hydrogen, deuterium and 3He, for storage rings, are discussed. Most of these targets make use of so-called storage cells in order to enhance the target thickness. The performance of targets used in medium and high-energy ion and electron storage rings is reviewed. Finally, future trends and possible improvements are discussed.