Kuzikov, S.

Paper	Title	Page
MOP65	Simple Theory of Thermal Fatigue Caused by RF Pulse Heating	168
	S. Kuzikov IAP, Nizhniy Novgorod
	The projects of electron-positron linear colliders imply that accelerating structures and other RF components will undergo action of extremely high RF fields. Except for breakdown threat there is an effect of the damage due to multi-pulse mechanical stress caused by Ohmic heating of the skin layer. A new theory of the thermal fatigue is considered. The theory is based on consideration of the quasi-elastic interaction between neighbor grains of metal due to the expansion of the thermal skin-layer. The developed theory predicts a total number of the RF pulses needed for surface degradation in dependence on temperature rise, pulse duration, and average temperature. The unknown coefficients in the final formula were found, using experimental data obtained at 11.4 GHz for the copper. In order to study the thermal fatigue at higher frequencies and to compare experimental and theoretical results, the experimental investigation of degradation of the copper cavity exposed to 30 GHz radiation is carried out now, basing on a 30 GHz free electron maser.
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
THP53	Quasi-Optical Components for Future Linear Colliders	730
	S. Kuzikov, G. G. Denisov, M. Yu. Shmelyov IAP, Nizhniy Novgorod J.L. Hirshfield Omega-P, Inc., New Haven, Connecticut
	This paper presents a concept of the quasi-optical RF system for future Ka-band electron-positron linear collider. According to this concept two RF feeding systems are considered: a Delay Line Distribution System (DLDS) and a pulse compressor based on the multi-mirror traveling-wave resonator. The DLDS is based on oversized waveguides. In such waveguides the so-called image multiplication phenomena are used for power launching, extracting, combining, and splitting of waves. Recent low power tests of mode launchers and other DLDS components are discussed. The 34 GHz pulse compressors, based on three and four-mirror resonators, are considered. The tests of the prototypes at a low power level under different modulation methods are discussed. The simulations and tests of mode converters, miter bends, RF loads, and other components, to be necessary for both compression systems, also are resulted.