Summary of polarized beams and targets

This paper presents an overview on polarized beams and targets. Irradiated target materials are becoming a standard. An impressive list of hydrogen-rich materials has been studied; the outcome seems to be that ammonia (NH3 or ND3) still performs best. Most emphasis is on negative ion sources, which allow multiturn injection into synchrotrons. Typical negative ion sources use a room-temperature polarized atom beam stage, followed by positive ionization by electrons before the 5 kV Na vapor channel double-electron adder. The proposed applications of H can be divided into two broad categories: those in which the proton-spin-selected atoms are used in situ - transformed by ionizing or scattering - in the stabilization cell, and those in which they are extracted by microwave-induced spin flips followed by magnetic field expulsion