# Presentation: 146414

## Multiple Beam Klystrons for Accelerators and Collider

- Patrick Ferguson, Liqun Song, Lawrence Ives
- Calabazas Creek Research, Inc.
- 20937 Comer Drive
- Saratoga, CA 95070
- (408) 741-8680
- _[Patrick@CalCreek.com](mailto:Patrick@CalCreek.com)__, __[RLIves@CalCreek.com](mailto:RLIves@CalCreek.com)_
- www.CalCreek.com

## Calabazas Creek Research, Inc.

- Leader in development of high power RF sources and components for fusion and high energy physics research. Products used in Europe, Asia, and the United States. Founded in 1994.

- 10 MW, W-Band Gyroklystron

## Current Programs

- 50 MW X-Band Multiple Beam Klystron (MBK)
- 201 MHZ, 5 MW MBK
- 100 W, W-Band MEMS TWT
- Improved cathodes for magnetron injection guns
- X-Band, 100 MW Sheet Beam Gun
- Finite Element, Adaptive Mesh Particle-In-Cell Code
- Finite Element, Adaptive Mesh Trajectory Code
- High power windows and waveguide components

- 500 kV Electron Gun for the University of Maryland

- Additional information at www.CalCreek.com

## Analytical Tools

- Gun and collector design – 3D Beam Optics Analysis, 3D OmniTrak, 2D Trak, 2D EGUN
- Magnetics – Maxwell 2D, Maxwell 3D
- Cavities – Superfish, HFSS, MAFIA
- Circuit – 21/2D KLSC, 3D MAGIC
- Thermal - ANYSYS

## X-Band MBK Program

- 50 MW, 11.424 GHz MBK for accelerator research

## Collector Design

- Collector design requires 3D magnetics and 3D beam simulations.

## 5 MW, 201 MHz MBK for Tevatron

- Number of Beams            8
- Frequency			201 MHz
- Power 			5 MW
- Efficiency			>55%
- Gain				46 dB
- Must operate linearly 15% below saturation
- Must fit in space available

- Funded by U.S. Department of Energy Small Business
- Innovation Research Grants DE-FG03-004ER83916

## Multiple Beam Fundamental Mode Cavity  Configuration

## Electron Gun Analysis

## Circuit Analysis(1) 

- Circuit Analysis(1)

- Initial design of MBK circuit utilizes 2D MAGIC and KLSC. Consistency is required. Final design uses 3D MAGIC. All components cold tested before and after assembly.

## Circuit Analysis(2) 

- Circuit Analysis(2)

- 3D MAGIC beam-RF Interaction

- Induced RF voltage in the output

## Window Design

- Window design performed with CCR’s scattering matrix code CASCADE. Thermomechanical analysis uses ANSYS.

## Anticipated Configuration

- Magnet coils

- Polepieces

- Coaxial Output (2)

- HV ceramic operates in air

## 10 MW, 201 MHz MBK for Tevatron

- Number of Beams            8
- Frequency			201 MHz
- Power 			10 MW
- Efficiency			>55%
- Gain				46 dB
- Must operate linearly 15% below saturation
- Must fit in space available

- Funded by U.S. Department of Energy Small Business
- Innovation Research Grants DE-FG03-004ER83916

## Cost Trade-Offs

- Klystron configuration based on total system cost, including power supply.
- Diversified Technologies Inc. provided cost comparison for solid state power supplies
- Number of beams based on power supply costs, cost of the electron gun, and cost of the klystron circuit

## 201 MHz MBK Status

- Phase I program successfully completed
- Phase II proposal due April 13, 2005
- Klystron and magnet would be built, tested, and delivered in the Phase II program to
-    Fermi National Accelerator Laboratory

## DOE SBIR Solicitation

- Grant applications are sought for new approaches for RF amplifiers for use in future _**Muon Collider**_. The RF amplifiers must have high peak power (>30 MW), 20 MHz (2 ms pulses) to 200 MHz (0.1 ms pulses). Higher power (>100 MW) at higher frequencies (from 30 microsec. At 400 MHz to 10 microsec. at 800 MHz) are also of interest. Pulse repetition rate compatibility = 15 Hz.

## 30 MW, 200 MHz MBK

- Configuration assumes 12 beams.Beam Voltage			115 kVCurrent				468 AMicroperveance		12.0 (effective)Efficiency			55%Circuit Length			2.96 meters

## 100 MW, 800 MHz MBK

- Configuration assumes 8 beamsBeam Voltage		250 kV (solid state supply)Current			752 AMicroperveance 	8.0 – effectiveEfficiency			>55%Gain			50 dBOutput Power		119 MWCircuit Length		2.98 meters
- Phase I SBIR proposal submitted to DOE in December 2004. Currently under review.

## Summary

-  Multiple beam klystrons are currently being designed and built
-  X-Band MBK design is complete, gun was successfully tested, and klystron is being assembled
-  201 MHz MBK initial design is complete. No significant problems are anticipated
-  Technology and experience available to successfully design and build MBK at other frequencies and higher power levels