2. ESS Gold A Proposal for a Next Generation European Neutron Source
K H Andersen, European Spallation Source
&
C J Carlile, Uppsala University

3. ESS will be the most intense neutron source in the world
First ideas 1985, full specification by 2025?
16th September 2016

4. Neutron source fluxes
Berkeley 37-inch cyclotron
350 mCi
Ra-Be source
Chadwick
1930
1970
1980
1990
2000
2010
2020
105
1010
1015
1020 1
ISIS
Pulsed Sources
ZINP-P
ZINP-P/
KENS
WNR
IPNS
ILL
X-10
CP-2
Steady State Sources
HFBR
HFIR
NRU
MTR
NRX
CP-1
1940
1950
1960
Thermal flux n/cm2-s
(Updated from Neutron Scattering, K. Sköld and D. L. Price, eds., Academic Press, 1986)
FRM-II
SINQ
SNS
ESS
J-PARC

5. Usable neutron brightness

6. Usable neutron brightness
Spallation
4 x brightness
per decade
Fission
1.2 x brightness
per decade

7. The neutron response to
a delta-function proton pulse
One, 5MW, 105ns pulse

8. Matched proton pulse/neutron moderation time
The Goldilocks solution
Not too hot,
not too cold,
but just right !
Matched proton pulse/neutron moderation time

9. The Goldilocks solution
ISIS, SNS, J-PARC have a 0.6 ms proton pulse length
ESS has a 2.86 ms proton pulse length
Moderation time for cold neutrons ~80 ms (22 l [Å] ms)
Short-pulse sources are mismatched by 80/0.6 = 140 times
Long-pulse sources are mismatched by 2860/80= 35 times
Both kinds of source are significantly mismatched

10. Why should we build ESS Gold ?
To understand the diversity & complexity
of new Materials
Thus to create better Materials for health,
climate & energy
And build better devices for industry
Nota bene!
Materials science is INCREMENTAL

11. …? Material Science & Innovation
“The Stone Age didn’t end for lack of stone”
Ahmed Zaki Yamani
Today
2016
Yesterday
1990
The future
2026 …?
We have to build the best facilities
with the best instruments
if we are to develop, understand, and harness New Materials

12. broad scientific reach
Neutrons have a
broad scientific reach

13. Materials Science and Society
NEW
MATERIALS
FUNCTIONAL
FOOD
SOLAR
ENERGY
MEDICINE
TAILOR
MADE
MATERIALS
COSMETICS
PACE- MAKERS
MOBILE PHONES
BIO FUEL
TRANSPORT
GEO SCIENCE
IMPLANTS
LIGHTING

14. What will a factor of 1000 facilitate?
The interplay of magnetic & electrical (sc) functionality
Routine polarisation analysis – exotic magnetism
Sample polarisation – contrast scanning – video protein crystallography
Fine resolution vibrational spectroscopy of molecular robots
Microscopic geometrical properties of topological materials
Microscopic understanding of medical healing processes
The dynamics of pharmaceutical lock & key mechanisms – delivery channels
Precision studies of bodily membranes – skin & cell walls
Engineering stresses in sub-mm3 gauge volumes – spider silk…
Dynamic tomography of combustion and corrosion
Nuclear magnetism at mK temperatures
Entanglement using interferometry
Gravitational quantisation, waves and gravitons
A finite value for the edm of the neutron
The probability of neutron-antineutron oscillations
The neutron lifetime to 100ms precision

15. time (μs)
Intensity

16. short-pulse
Intensity
time (ms)

17. Intensity
long-pulse
time (ms)

18. Intensity
time (ms)

19. Intensity
time (ms)

20. Intensity
time (ms)

21. Intensity
time (ms)

22. 80 msec pulse
35x brightness
Intensity
time (ms)

23. …now that they’ve found
LHC !
The World’s Ultimate
Slow Neutron Source ?
…now that they’ve found
the Higgs boson
1000 x SNS & 35 x ESS

24. Potential Upgradeability
2nd target and neutrino source
Compressing the msec pulse to match the moderating time of cold neutrons
2.86ms to 80µs
4 rings of 1100m Oce
Each containing 25 pulses of 105ns
Permanent magnets
Peak intensity gain of 35 times
Total gain of 1000 times today
Reduces the instantaneous power on the target cf short pulsed source
D. McGinnis, M. Lindroos
& R. Miyamoto IPAC 2013

25. 2065
ESS Gold