1. Targets & conversion to secondary radiation summary
Chris Densham

2. the energy problem – a range of opinions
green enthusiast:
sun and wind offer plenty of energy, no nuclear, no fossil, skepticism on tech
technology enthusiast:
fast reactors, fusion etc. ; optimism about technologies
contemplative:
technological development is too fast, consequences not predictable, go slower!
Fact information: David McKay, Sustainable Energy without the Hot Air
withouthotair.com, talk: youtube.com/watch?v=-5bVbfWuq-Q

3. Technology progression
What to build next?
Years

4. Technology progression
Years

5. Technology progression

6. Technology progression

7. Cold Source Brightness a Metric of Efficiency?

8. Some neutron flux numbers for SINQ
Inside the cold D2 moderator n/cm2/s/mA
Neutron Guide Entrance (towards Neutronenleiterhalle) n/cm2/s/mA
End of Guides n/cm2/s/mA
On sample (at 3 Å) ~ n/cm2/s/mA
Proton
Detector
Target

9. Conclusion
Target
Moderator
Guides
Instruments
Shielding
Accelerator
A separate optimization of the different integral parts of a spallation neutron source is inefficient.
All integral parts – starting from the proton beam distribution down to the neutron instrument - have to be seen as a chain of components and should be optimized accordingly.
A large number of neutrons is «lost» due to the isotropicity of moderation  directional moderators
Neutron instrument setup currently tend to remove a large portion of neutrons due to chopper etc. systems. Could one use those «unwanted» neutrons? Instrument design.

13. Muon Facilities in the world
ISIS
(pulse)
J-PARC
(pulse)
TRIUMF (CW)
PSI (CW)
Country
Japan
U.K.
Switzerland
Facility
J-PARC MUSE
RAL ISIS
PSI
proton energy [GeV]
3.0
0.8
0.59
proton intensity [MW]
1.0 (Goal)
0.16
1.3
m+ [/s] (surface)
3108 (U line)
6105
3107
m- [/s]
1107
7104
2107
CW / Pulse
Pulse (25Hz)
Pulse (50Hz) CW
50 GeV Synchrotron
(0.75 MW)
3 GeV Synchrotron
(25 Hz, 1MW)
Materials and Life Science
Experimental Facility
（Muon & Neutron)
Linac
(181MeV  400 MeV)
Pulsed muon beam don't need to mind about the pileup. No limit for proton beam intensity, but a highly segmented spectrometer is needed for mSR.

14. In-Target Production Yield Example with 132Sn
Studies of neutron-rich nuclei beyond the doubly magic 132Sn are of key importance to investigate the single particle structure above the N=82 shell closure and find out how the effective interaction between valence nucleons behaves far from stability
TRIUMF-ISAC
CERN-ISOLDE
IBS-RISP
LNL-SPES
EURISOL
ARIEL
FRIB p e- U
Energy [MeV]
500 70 40
1000 50
47600
Intensity [µA]
100
2.5
1,000
200
10,000
5,000
Power in target [kW] 3 8 90
In-target Production yield 132Sn [pps]
5e10 to 1.5e11 for 10 μA
~1e10
(6e8 delivered)
~2e9
1.6e9
0.5 GeV
3.9e9
1.4e7*
Normalized in target production yield [pps/µA]
5e9 to 1.5e10
4e9
2e6
8e6
3e9
3.9e5
3e3 *
* Already accelerated!
F. Pellemoine, February Proton Driver Efficieny Workshop

15. Motivations for ‘Figures of Merit’
End-to-end simulations of accelerator driven facilities highly sophisticated & complex
Computationally expensive – e.g. genetic algorithm
‘Black box’ type output
Can be difficult to identify ‘design guidelines’
‘Listen to the robot’ for the answer
Useful to have a tool that (ref R.Zwaska) :
Can factorise problems – orthogonal to genetic algorithm
Is readily understood
Can apply to a distribution
Also useful to have a tool to compare reliability (materials or engineering issues)