1. A Compact Proton Accelerator An Industrial Perspective
Oliver Heid Corporate Technology Siemens AG
Copyright © Siemens AG All rights reserved.

2. We need 10x neutrons per second
End User Perspective
We need 10x neutrons per second
How much does a neutron cost to produce? 2

3. Cost of Neutron Production
Infrastructure size
Return on investment
Capital
Costs
Energy
Costs
Running costs
Reliability
Service Costs
Penalty clauses
Customer dissatisfaction
Lost reputation

4. A Compact Proton Accelerator : Outline
Introduction to Neutron Spallation Drivers : LINAC
Commercial Considerations of a Spallation Driver
Proposal for a Spallation Driver
Accelerator Activities
Copyright © Siemens AG 2010.

5. A Compact Proton Accelerator : Outline
Introduction to Neutron Spallation Drivers : LINAC
Commercial Considerations of a Spallation Driver
Proposal for a Spallation Driver
Accelerator Activities
Copyright © Siemens AG 2010.

6. Spallation is the most energy efficient neutron production route
Why Spallation?
Spallation is the most energy efficient neutron production route 6

7. Spallation Neutron Production
High Intensity
Proton Beam
Application
Users
Neutron Spallation
Target 7

8. Accelerator Based Neutron Production
RF Converter
Heat
Cavity Losses
Heat
Target Losses
Heat
Wall
plug
RF Power
Proton Beam
Neutrons
Target
Waste heat recovery may significantly increase overall efficiency 8

9. Spallation Process Efficiency
Yield Y – neutrons per proton (n/p) as function of particle energy U and target atomic number A
JM Carpenter, “Pulsed Spallation Sources for Slow Neutron Scattering” NIM 145 (1977) 91

10. State of the art high power LINAC
Spallation Neutron Source (SNS)
Ion Source
RFQ
Alvarez DTL
CH Cavity 10

11. Spallation Driver : LINAC Energy Balance
Losses in the
accelerator
Beam power 11

12. A Compact Proton Accelerator : Outline
Introduction to Neutron Spallation Drivers : LINAC
Commercial Considerations of a Spallation Driver
Proposal for a Spallation Driver
Accelerator Activities
Copyright © Siemens AG 2010.

13. The energy cost of a neutron : J/neutron
Length – 100m
Z – 35M/m
There is an optimum at surprisingly low energies (~ 400MV)
Large beam currents improve efficiency
Longer accelerators generally have incrementally higher efficiency
Energy – 500MeV
Z – 35M/m
Energy – 500MeV
Z – 35M/m

14. Energy Costs Energy Cost @ 0.04 $kWh – 8.4M€ per annum 100m long LINAC
Application Need
1018 neutrons/sec
Hygiene Factors
Compact – 100m
Space Charge – 200mA pulsed beam
Kilpatrick Limit – 5MV/m E field
Peak Pulse RF Power – 1GW
Physics Limits
Cost Optimise for End Energy
200mA pulsed beam
100m length
Z – 35M/m
Optimum Energy – 500MeV
Duty Cycle Definition
MeV = 20mA CW
10% duty cycle
Calculate Energy Useage
x J/neutron with RF – 75%
21MW
100m long LINAC
500MeV end energy
10MW beam power
50% wallplug efficiency
Energy 0.04 $kWh – 8.4M€ per annum

15. Energy Costs Energy Cost @ 0.04 $kWh – 8.4M€ per annum
Application Need
1018 neutrons/sec
Hygiene Factors
Compact – 100m
Technology Focus
Areas
Space Charge – 200mA pulsed beam
Kilpatrick Limit – 5MV/m E field
Peak Pulse RF Power – 1GW
Physics Limits
Cost Optimise for End Energy
200mA pulsed beam
100m length
Z – 35M/m
Optimum Energy – 500MeV
Duty Cycle Definition
MeV = 20mA CW
10% duty cycle
Calculate Energy Useage
x J/neutron with RF – 75%
21MW
100m long LINAC
500MeV end energy
10MW beam power
50% wallplug efficiency
Energy 0.04 $kWh – 8.4M€ per annum

16. Commercial Perspective : Capital Costs
Cin = tunnel (13k€/m)
Cacc = accelerating structure (125k€/m)
Crf = RF (see grapth)
Cfront= front end fixed cost (5M€)
~ 40M€ for 1018 neutrons/sec IF
RF costs 10 cents per W
60 cents/W
10 cents/W
1 cents/W

17. Commercial Perspective : Capital Costs
Cin = tunnel (13k€/m)
Cacc = accelerating structure (125k€/m)
Crf = RF (see grapth)
Cfront= front end fixed cost (5M€)
~ 40M€ for 1018 neutrons/sec IF
RF costs 10 cents per W
60 cents/W
~ 20M€ for 1018 neutrons/sec IF
RF costs 1 cent per W
10 cents/W
1 cents/W

18. Commercial Perspective : Capital Costs
Cin = tunnel (13k€/m)
Cacc = accelerating structure (125k€/m)
Crf = RF (see grapth)
Cfront= front end fixed cost (5M€)
~ 40M€ for 1018 neutrons/sec IF
RF costs 10 cents per W
60 cents/W
~ 20M€ for 1018 neutrons/sec IF
RF costs 1 cent per W
10 cents/W
1 cents/W
RF Technology Focus

19. Reliability

20. Reliability
Technology Focus
Front End
RF Power
Target Design

21. A Compact Proton Accelerator : Outline
Introduction to Neutron Spallation Drivers : LINAC
Commercial Considerations of a Spallation Driver
Proposal for a Spallation Driver
Accelerator Activities
Copyright © Siemens AG 2010.

22. Spallation Driver Proposal
40M€ capital cost
8M€ energy costs
99.99% uptime
1018 neutrons/sec
Control System
200mA
5% DC
500MeV
1H – DTL
1H – DTL
1H – DTL
1H – DTL
1H – DTL
1H – DTL
5m, 2MeV
10m, 50MeV
100m, 500MeV
Low Energy
“Defence in Depth”
Mid to High Energy
“Adaptive Self Healing Array”

23. Mid and High Energy Section
Control System
Adaptive Control system
(Ai,i)………………………………………………… (An,n)
Optimized parameter set
Solid State Direct DriveTM
RF Sources
Array of independent cells
Self healing array of accelerating substructures
Each cavity individually controlled (phase, amplitude, frequency)
Control System dynamically redistributes according to fault modes

24. Multiple layers of redundancy
Low Energy Section
100mA beam IS
Funnel
RFQ
DTL
200mA beam
100mA beam
Multiple layers of redundancy
Pre-acceleration before DTL injection mitigates space charge

25. A Compact Proton Accelerator : Outline
Introduction to Neutron Spallation Drivers : LINAC
Commercial Considerations of a Spallation Driver
Proposal for a Spallation Driver
Accelerator Activities
Copyright © Siemens AG 2010.

26. Accelerator Activities
40M€ capital cost
8M€ energy costs
99.99% uptime
GOAL
Control System
High Current
Ion Sources
RF Power
High Current
RFQ
Cavity Design
200mA
5% DC
500MeV
1H – DTL
1H – DTL
1H – DTL
1H – DTL
1H – DTL
1H – DTL
Control System
5m, 2MeV
Funneling
10m, 50MeV
100m, 500MeV
Low Energy
“Defence in Depth”
Mid to High Energy
“Adaptive Self Healing Array”

27. RF Power: Solid State Direct Drive™
Distributed independent RF sources enable Ultra High Power
Independent control of each cavity
No external RF source, waveguide or mode coupler
Distributed topology enables Robust Design

28. RF Power: Solid State Direct Drive™
Silicon Carbide
vJFET
SiC is intrinsically 10x faster than Silicon
Significantly enhanced power compared to Si.
Radiation hard
Hyperfast body diode survives reflected RF power
Large positive Rdson temperature coefficient

29. Solid State Direct Drive™
20kW RF power module – SiC solid state
1 MW RF power test cavity
[1] O Heid, T Hughes IPAC 2010
[2] O Heid, T Hughes LINAC 2010
[3] O Heid, T Hughes HB2010
[4] M Hergt et al, PP Conf 2010
First Results Summer 2010 [1,2,3,4]

30. Solid State Direct Drive™
Cost – 10 cents/Watt 
Efficiency – 80% wall plug - RF power conversion 
Reliability – redundant, gracefully degrading system  

31. SICED, SiCrystal, INFINEON: Radiation-hard ultra fast high power switches
MIT Boston, FIAS Frankfurt, Univ of Huddersfield : Advanced materials
Rossendorf Dresden, Dreebit Dresden, IAP Frankfurt : Advanced ion sources
IAP Frankfurt, BINP Novosobirsk, MEPHI Moscow, FNAL Illinois, LBNL California, JFZ Juelich, Univ Oxford: Accelerator Physics
MIT Boston, CT PP: Advanced control systems

32. Thank you for your attention!

33. Contact Oliver Heid Vice President Technologies and Concepts
CT T P HTC
Mozartstrasse 57
91052 Erlangen
Germany
Phone: +49 (9131)
Fax: +49 (9131)
© Siemens AG All rights reserved.