A high-efficiency, high-power magnicon at 34.272 GHz has been designed and built as a microwave source to develop radio frequency (RF) technology for future multi-TeV electron-positron linear colliders. To develop this technology, this new RF source is being perfected for necessary tests of accelerating structures, RF pulse compressors, RF components, and to determine limits of breakdown and metal fatigue. The design of this high-power amplifier tube, as well as the first experimental results are presented.

Commissioning of the 34-GHz, 45-MW pulsed magnicon

Recent commissioning of a 45-MW peak power 34.3 GHz magnicon amplifier makes possible, for the first time, high-power tests of components and structures for a possible future high-gradient millimeter-wave linear accelerator. A brief survey is presented of the status of this Ka-band magnicon and component development efforts now underway.

http://ieeexplore.ieee.org/iel5/9723/30686/01422197.pdf

Technology developments for a future millimeter-wave high-gradient linear accelerator

New results of experimental tests of the Yale/Omega-P Ka-band magnicon are presented. The main goal is to achieve stable and repeatable operation necessary for operation of a high-power accelerator test facility. In order to direct the beam along the tube axis, steering coils were installed between the gun and the RF system, thereby allowing an increase in pulse width and achievement of good stability and repeatability of the output signal. The test facility is briefly described.

34 GHz Magnicon for a Ka-band Test Facility

Achievement of high acceleration gradients in roomtemperature structures requires basic studies of electrical and magnetic RF field limits at surfaces of conductors and dielectrics. Facilities for such studies at 11.4 GHz have been in use at KEK and SLAC; facilities for studies at 17.1 GHz are being developed at MIT and UMd; and studies at 30 GHz are being conducted at CERN using the CLIC drive beam to generate short intense RF pulses. Longer pulse studies at 34 GHz are to be carried out at a new test facility being established at the Yale Beam Physics Laboratory, built around the Yale/Omega-P 34 GHz magnicon. This high power amplifier, together with an available ensemble of components, should enable tests to be carried out at up to 9 MW in 1 μsec wide pulses at up to four output stations or, using a power combiner, at up to 35 MW in 1 μsec wide pulses at a single station. RF pulse compression is planned to be used to produce 100-200 MW, 100 nsec pulses or GW level 1 μsec wide pulses in a resonant ring. A number of experiments have been prepared to utilize multi-MW 34 GHz power for accelerator R&D, and users for future experiments are encouraged to express their interest.

https://epaper.kek.jp/e06/papers/tupch164.pdf

Ka-band test facility for high gradient accelerator r&d*

A high efficiency, high power magnicon at 34.272 GHz has been designed and built as a microwave source to develop RF technology for a future multi‐TeV electron‐positron linear collider. The tube is designed to provide a peak output power of ∼45 MW in a 1 microsecond pulse, with a gain of 55 dB, using a 500 kV, 220 A, 1 mm‐diameter electron beam. The status of the tube itself as well as the near‐term experimental program is presented.

34 GHz, 45 MW Pulsed Magnicon

Efforts are underway within the accelerator community to develop high-gradient RF accelerators using microwave sources at relatively high frequencies (in particular, at 34.272 GHz). Yet no corresponding high-power components providing pulse compression, transmission and input coupling to the accelerating structure are currently available. Results of investigations of many components including resonator passive pulse compressor, controllable launcher for a DLDS system, low-loss miter bends, and mode converters, are presented.

A.G. Litavk

Papers

Study of Ka-band components for a future high-gradient linear accelerator