| Paper |
Title |
Page |
| TUP058 |
The RF Design of a HOM Polarized RF Gun for the ILC
|
379 |
| |
- J. W. Wang, J. E. Clendenin, E. R. Colby, R. H. Miller
SLAC, Menlo Park, California
- J. W. Lewellen
ANL, Argonne, Illinois
|
|
| |
The ILC requires a polarized electron beam. While a highly polarized beam can be produced by a GaAs-type cathode in a DC gun of the type currently in use at SLAC, JLAB and elsewhere, the ILC injector system can be simplified and made more efficient if a GaAs-type cathode can be combined with a low emittance RF gun. Since this type of cathode is known to be extremely sensitive to contamination including back bombardment by ions, any successful polarized RF gun must have a significantly improved operating vacuum compared to existing RF guns. We present a new RF design for an L-Band NC RF gun for the ILC polarized electron source. This design incorporates a higher order mode (HOM) structure, whose chief virtue in this application is an improved conductance for vacuum pumping on the cathode. Both 2-D and 3-D models have been used to optimize the RF parameters with two principal goals: first to minimize the required RF power; second to reduce the peak surface field relative to the field at the cathode in order to suppress field emitted electron bombardment. The beam properties have been simulated initially using PARMELA. Vacuum and cooling considerations for this design are discussed.
|
|