Non-termal outgassing

Non-thermal outgassing, i.e., the outgassing stimulated by the impact of energetic particles, is the predominant source of gas during the operation of accelerators and storage rings. This source of gas is not constant and changes with the integrated beam intensity or according to the circulating beam(s) characteristics. In this contribution, the various aspects of stimulated desorption will be reviewed in the case of ions, electrons, or photons impacting on technical materials commonly encountered in accelerators. Finally the consequences of these phenomena on the operation of accelerators will be described.