[en] The cavity resonator is designed axially symmetrical with respect to the beam axis. It consists of two end pieces being composed of two plate-shaped half shells and welded together at the outer border and at the inner opening for the radiation passage. Both end pieces are connected by means of pipes forming a cylindrical structure with interrupted side walls. Through the end pieces and the pipes there may be passed a coolant, especially helium if a niobium material for superconduction is used. The surfaces of the end pieces and the pipes are chemically or electrochemically refined. (DG)

[en] A cavity of an acceleration unit built up from one or more individual resonators is filled to about half way with ceramic grinding bodies and with water, and turned slowly at about 9 rpm. The rotation is maintained for about a week. The inner surface of the cavity is thus smoothed and freed of faults, so that the cavity can be used without difficulty in superconducting operation with improved properties. By this simple process, success is achieved in increasing the practically possible longitudinal field strength for acceleration by at least a factor of 2 or more, i.e. one can save at least half the acceleration units. To remove grinding wear, the cavity is also filled with an acid mixture of about 1 part of HF, 1 part of HNO₃ and 6 parts of H₃PO₄ and cleaned, and the surface is etched. (orig.)

No abstract available

[en] The invention deals with a method for the anodic oxidation of the inner surface of superconducting niobium hollow bodies such as e.g. used as high-frequency resonators, separators for particle accelerators or in tube-form as conductor for superconducting cables. According to the invention, the niobium hollow body is continuously turned around a rotational axis running through the opening, so that the individual parts of its inner surface are dipped into the electrolyte after one another, so that the gases formed on the cathode below the electrolyte level do not touch the inner surface of the niobium body. There must always be a free space present connected through the opening to the outer surroundings between the electrolyte level and all parts of the inner surface of the niobium hollow body above it. (HPOE.)

[en] Performance of niobium superconducting cavities are highly dependent of surface quality. Means to decrease energy dissipation are briefly reviewed

[en] Using a six cell periodic plane symmetric structure, values of resonant frequencies and the quality factor Q₀ were measured for different field configurations of the accelerating and deflecting modes in the S-band. Best results were obtained for a structure which is open along its sides, resonating in the π/2 mode

[en] The paper summarizes the status of the most advanced superconducting slow-wave resonators of the helical, split-ring, re-entrant, Alvarez and Iris type

[en] I have restricted this compilation to those applications of rf superconductivity where high fields are needed. So I have left aside applications such as frequency standards etc. I shall instantly show a table in which the laboratories upon whose work I will report are listed. I think it is important to point out that some superconducting devices have been in duty now for some time, some for several thousand hours. A question is what Q-values or what surface resistances can be obtained and high β-structures and low β-structures are described. (orig./WTR)

[en] Performance and applications of superconducting cavities and superconducting magnets, using liquid or superfluid helium, are reviewed

[en] During the past year the DOE awarded a contract to build the superconducting booster proposed in 1982. Although the majority of the funds ($8M) of the project are construction funds included in the DOE contract, part of the project is to be done with state funds ($1.03M) and part with the operating funds (3 FTE personnel as well as costs of prototyping the resonators). Therefore it is appropriate to outline the progress in this report. The overall design was changed somewhat from that described in last year's Annual Report. Instead of 12 split ring resonators optimized for beta = 0.10 and 12 for beta = 0.16, the author has chosen to use 16 quarter wave resonators optimized for beta = 0.09 and 16 for beta = 0.18. The quarter wave resonators, which have two accelerating gaps instead of the three of the split rings, have a wider transit time factor, which is favorable for accelerating a broader range of particle masses. The quarter wave resonators are to be built of lead plated copper, following the design of Ben-Zvi and Brennan