1. Neutron Detector Systems at ESS
F. Mezei with R. Hall-Wilton
Technical Coordinator Detector Group Leader
Annual Review 2015

2. ESS consortium Host Countries of Sweden and Denmark
47,5% Construction % Operations
In-kind Deliverables ~3%
Cash Investment ~97%
Non Host Member Countries
52,5% Construction
85% Operations
In-kind Deliverables ~ 70%
Cash Investment ~ 30%

3. Spallation sources: state-of-the-art
SNS (Oak Ridge)
60 Hz proton pulse rate
< 1 s pulse length
1 MW beam power
 instantaneous power: 17 GW
1 GW
Monolith
liner
Steel
shielding

4. ESS: improved efficiency spallation source
SNS (Oak Ridge)
60 Hz proton pulse rate
< 1 s pulse length
1 MW beam power
 instantaneous power: 17 GW
1 GW
simplify
Monolith
liner
Steel
shielding
ESS (Lund)
14 Hz proton pulse rate
2.8 ms pulse length
5 MW beam power
 simpler, cost equivalent accelerator
 instantaneous power: 0.15 GW

5. Scope & Budget & In-kind potential
Total construction cost: € 1,843 billion (2013)
Proton beam power: 5 MW
Proton beam energy: 2 GeV
User operation: 2023 (> 400 experiments/year)
Target station
€ 154M
Accelerator
€ 522M
Instruments
€ 350M
In-kind
Cash

6. Performance: slow (< eV) neutron source brightness
 = 3 Å
h=3 cm, w=8 cm
cold moderator
TDR (2013)
Conv. mod (2010) H2
p-H2 n
2x10 14
4x10
6x10
 = 1.5 Å
h=3 cm, w=8 cm thermal mod. optimal position
Conv. &TDR (2013)
ESS 5 MW, 3 cm flat
moderator
ESS 5 MW, TDR 2013
ISIS TS1 128 kW
ISIS TS2 32 kW
SNS 1 MW
J-PARC 300 kW
ILL 57 MW
Performance: slow (< eV) neutron source brightness
“Butterfly”
bi-spectral
moderator:
cold, thermal
“Butterfly “ bi-spectral moderator
ESS pulse
shapes
ESS pulse shapes

7. ESS detector needs: quantities and resolutions
50 % of total
In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end
arXiv:

8. ESS detector needs: costs, availability, etc
Other key parameters:
- costs
- availability
- established reliability (>10 years)
Other “good to have” parameters:
- counting rate: up to 107 n/cm2/s
- efficiency > %
Main issue:
- 3He got rare after 911
- back, but more expensive
10 M€

9. Options and collaborations
In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end
“Commercial-off-the-shelf” (made on command): strongly reduced share planned

10. Efficiency of Boron-10 Detectors
Single layer is only ca.5%
Multilayer configuration: still lower costs vs. 3He
In the presentation I will talk about Chopper system scope, Schedule, Budget risks and then I summarize it at the end
JINST 8 (2013) P04020

11. 10B demonstrator: quality, cheap coatings Mass production possible
Done in Linkoping
JAP 111 (2012)
Coatings complete in June
104m^2
ca. 25k items
<6 weeks coating time
irradiation tests done:
J. Rad. Phy. + Chem in press

12. 10B demonstrator: quality, cheap coatings
Mass production possible for large area
Done in ILL
1 column (10 cm width) per week production rate once tooling is available

13. Thank you…