| Paper | Title | Page |
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| WEPMA109 | Positron Injector Accelerator and RF System for the ILC | 473 |
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Due to the extremely high energy deposition from positrons, electrons, photons and neutrons behind the positron target, and because a solenoid is required to focus the large emittance positron beam, the 1.3 GHz pre-accelerator has to use normal conducting structures up to energy of 400 MeV. There are many challenges in the design of the normal-conducting portion of the ILC positron injector system such as obtaining high positron yield with required emittance, achieving adequate cooling with the high RF and particle loss heating, and sustaining high accelerator gradients during millisecond-long pulses in a strong magnetic field. Considering issues of feasibility, reliability and cost savings for the ILC, the proposed design for the positron injector contains both standing-wave (SW) and traveling-wave (TW) L-band accelerator structures. A short version of the new type of the SW section is under fabrication and testing, an updated status report is given. This paper also covers the acceleration vs. deceleration for pre accelerator sections, SW vs. TW structures, as well as the longitudinal matching from target to linac and linac to damping ring.
* Work supported by U. S. Department of Energy, contract DE-AC02-76SF00515. |