Speaker
Description
A dielectric assist accelerating (DAA) structure, a type of dielectric loaded accelerating structures, is greatly superior in power efficiency compared with the conventional disk-loaded copper structures. The advantage of DAA structure is that it has an extremely high quality (Q0 > 10^5@C-band) factor and a high shunt impedance at room temperature since the electromagnetic field distribution of the accelerating mode can be controlled by the geometry of its structure to reduce the wall loss on metallic surface. However, an accelerating gradient of C-band DAA structure is currently limited about 12 MV/m due to multipactor and discharge.
We are developing X-band DAA structures to achieve higher accelerating gradient in DAA structure. These structures are tested using the X-band high power test facility named Nextef2 at KEK. In the high-power test, we plan to perform short pulse RF excitation using step pulse input in DAA structures to verify the potential of them to generate a high accelerating field. In this conference, we will report the achievements and progress in the development of DAA structure.
