The Plasma Window: a Windowless High Pressujxe-vacuum Interface for Vari3us Accelerator Applications*

The Plasma Window is a stabilized plasma arc used as an interface between accelerator vacuum and pressurized targets. There is no solid material introduced into the beam and thus it is also capable of transmitting particle beams and electromagnetic radiation with low loss and of sustaining high beam currents without damage. Measurements on a prototype system with a 3 mm diameter opening have shown that pressure differences of more than 2.5 atmospheres can be sustained with an input pressure of IO-6 Torr. The system is capable of scaling to higher-pressure differences and larger apertures. Various plasma window app!ications for synchrotron light sources, high power lasers, internal targets, high current accelerators such as the HAWK, ATW, APT, DARHT, spallation sources, as well as for a number of commercial applications, will be discussed.