1. Multiple Beam Klystrons for Accelerators and Collider
Patrick Ferguson, Liqun Song, Lawrence Ives
Calabazas Creek Research, Inc.
20937 Comer Drive
Saratoga, CA 95070
(408)

2. 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

3. 500 kV Electron Gun for the University of Maryland
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

4. 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

5. X-Band MBK Program
50 MW, GHz MBK for accelerator research

6. Collector Design
Collector design requires 3D magnetics and 3D beam simulations.

7. 5 MW, 201 MHz MBK for Tevatron Number of Beams 8 Frequency 201 MHz
Power 5 MW
Efficiency >55%
Gain 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

8. Multiple Beam Fundamental Mode Cavity Configuration

9. Electron Gun Analysis

10. 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.

11. Circuit Analysis(2) Induced RF voltage in the output
3D MAGIC beam-RF Interaction

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

13. Anticipated Configuration
Magnet coils
HV ceramic operates in air
Polepieces
Coaxial Output (2)

14. 10 MW, 201 MHz MBK for Tevatron Number of Beams 8 Frequency 201 MHz
Power MW
Efficiency >55%
Gain 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

15. 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

16. 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

17. 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.

18. 30 MW, 200 MHz MBK
Configuration assumes 12 beams. Beam Voltage kV Current A Microperveance (effective) Efficiency 55% Circuit Length meters

19. 100 MW, 800 MHz MBK
Configuration assumes 8 beams Beam Voltage 250 kV (solid state supply) Current A Microperveance 8.0 – effective Efficiency >55% Gain 50 dB Output Power 119 MW Circuit Length meters
Phase I SBIR proposal submitted to DOE in December Currently under review.

20. 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