Syratchev, I.

Paper	Title	Page
THP28	Multi-Mode SLED-II Pulse Compressors	660
	S. Kuzikov, Y.Y. Danilov, G. G. Denisov, V. G. Paveliev, D. Yu. Shegol'kov, A. A. Vikharev IAP, Nizhniy Novgorod I. Syratchev CERN, Geneva
	Compact SLED-II pulse compressors are considered. The primary idea of S. Kazakov to use a set of the cylindrical multi-mode cavities, to be free of high-Q resonances around the 11.4 GHz, is analyzed. This idea is developed, in order to provide more delaying time per miter of the line. Another idea to provide compactness is to avoid two-channel scheme with 3 dB coupler usually used for SLED-II pulse compressors. A reflectionless delay line is built in this case, using coupling in a form of the non-symmetrical mode converter. SLED-II pulse compressors of higher frequency bands also are considered. It is suggested to shape these compressors on a base of the multi-mirror transmission lines. The operating mode in this case is a Gaussian wavebeam traveling between mirrors. Various configurations of the mirrors are compared from the point of view of maximum of compactness at the given pulse duration. The results of the preliminary experiments at low power level are discussed.
	Transparencies
THP34	A High-Power Test of an X-Band Molybdenum-Iris Structure	678
	W. Wuensch, A. Grudiev, T. Heikkinen, I. Syratchev, T. Taborelli, I. Wilson CERN, Geneva C. Adolphsen SLAC/NLC, Menlo Park, California S. Döbert SLAC, Stanford
	In order to achieve accelerating gradients above 150 MV/m, alternative materials to copper are being investigated by the CLIC study. The potential of refractory metals has already been demonstrated in tests in which a tungsten-iris and a molybdenum-iris structure reached 150 and 193 MV/m respectively (30 GHz and a pulse length of 15 ns). In order to extend the investigation to the pulse lengths required for a linear collider, a molybdenum-iris structure scaled to X-band was tested at the NLCTA. The structure conditioned to only 65 MV/m (100 ns pulse length) in the available testing time and much more slowly than is typical of a copper structure. However the structure showed no sign of saturation and a microscopic inspection of the rf surfaces corroborated that the structure was still at an early stage of conditioning. The X-band and 30 GHz results are compared and what has been learned about material quality, surface preparation and conditioning strategy is discussed.
	Transparencies
THP59	Low Level RF Including a Sophisticated Phase Control System for CTF3	748
	J. Mourier, R. Bossart, J. Nonglaton, I. Syratchev, L. Tanner CERN, Geneva
	CTF3 (CLIC Test Facility 3), currently under construction at CERN, is a test facility designed to demonstrate the key feasibility issues of the CLIC (Compact LInear Collider) two-beam scheme. When completed, this facility will consist of a 150 MeV linac followed by two rings for bunch-interleaving, and a test stand where 30 GHz power will be generated. In this paper, the work that has been carried out on the linac’s low power RF system is described. This includes, in particular, a sophisticated phase control system for the RF pulse compressor to produce a flat-top rectangular pulse over 1.4 μs.