AN INTENSE FLUORINE ATOM BEAM SOURCE

The important properties of thermal ovens for producing intense beams of F atoms by thermal dissociation of F-2 are analysed. After reviewin g previous constructions a new source made of a single crystal of MgF2 is described and characterized. This source has been tested for more than 3000 h at temperatures up to 1000 degrees C with a mixture of 10% F-2 in Ar at pressures up to 12 bar. A degree of dissociation of 50% and a F atom beam velocity spread Delta v/v of about 7% were achieved.