1. RF systems introduction
Anders Sunesson
RF group leader
June 7, 2016

2. An artists impression of ESS

3. A builder realisation: Gallery/tunnel today

4. Overview
RF systems
RF distribution systems
Risk workshop summary

5. ESS RF system building blocks
Modulator
LLRF
Distribution
System
Phase ref
Cavity
Interlock

6. RF systems RF provides the power that accelerates
155 cavities shall be powered, each from one station
RF systems are placed between the wall power plug and the cavity coupler
Many and complex subsystems
Cooling water 50 deg C or more for collectors, loads

7. RF Technical performances
Spokes
Medium β
High β
DTL
MEBT
RFQ
LEBT
Source
HEBT & Contingency
Target
2.4 m
4.5 m
3.6 m
40 m
54 m
75 m
174 m
75 keV
3.6 MeV
90 MeV
220 MeV
570 MeV
2000 MeV
MHz
MHz
Energy (MeV)
Frequency /MHz
No. of Cavities βg
Temp / K
RF power /kW
Source
0.075 - –
~300
LEBT
RFQ
3.6
352.21 1
1600
MEBT 3 20
DTL 90 5
2200
Spoke
220
26 (2/CM)
0.5 βopt ~2
330
Medium β
570
704.42
36 (4/CM)
0.67
870
High β
2000
84 (4/CM)
0.86
1100
HEBT

8. ESS accelerator power profile
Average beam power: 5 MW > 130 MW peak
Pulse repetition rate: 14 Hz
Beam pulse length: 2.86 ms
36 Medium beta cavities: 704 MHz
1.5 MW Klystrons
26 spoke cavities:
352 MHz
Tetrodes
Normal-conducting Linac:
One RFQ and 5 DTL tanks
6 off 352 MHz klystrons
3 MW
3 Solid state amplifiers for bunchers
352 MHz, 30 kW
84 High beta cavities: 704 MHz
1.2 MW MB IOTs (klystrons as backup)

9. RF distribution system
Modulator
LLRF
Distribution
System
Cavity
Interlock

10. RF distribution
Transports RF power from Amplifier output to cavity coupler
There will be several km of waveguides
Arc detectors
Directional couplers
Circulators
Loads
In-kind delivery
Courtesy of Rutambhara Yogi

11. Schedule RF systems
The RF systems shall be ready to power beam for the linac up to and including medium beta by June 2019
RF for the High Beta part shall be ready to power beam by 2022
Installation shall start autumn 2017

12. Risk workshop A risk workshop was held at ESS on May 10 2016
It turned out to be a good kick-off and project workshop
Indico:
The workshop also issued a list of decisions and actions, see next slides

13. Risk workshop decisions
The following CDRs are required:
Tender 1: Waveguides, elbows, coaxial components
Tender 2: Standard RF components (bellows, shutter switch, directional couplers) (June 7th 2016)
Tender 3: Support structure
Tender 4: Circulators and loads
Tender 5: Arc detectors
Agreement on remaining CDR dates needed
Continue weekly Skype, Morten to paricipate in last meeting every month

14. Risk Workshop actions
Share prototype development contracts with partners (Yogi)
Finalise cooling design for waveguides in stubs (Morten)
Update SoW: 4-loop DCs; waveguide cooling stubs (Yogi)
Finalise PSS interface (Yogi, Morten)
Arrange Gallery review prior to CDR (John)
Share project plan incl resources with ESS (Paul)
Update P6 plan to align with UK plan (Yogi)
CE marking – consider wording on safety and share w ESS (Rob)

15. Actions II Summarise the CHESS documents (Yogi, Paul)
Ask for longer access to CHESS for partners (Yogi)
Send risk register to ESS (Paul)
ESS and UK to agree on PQP, share with ESS June 24 (Paul)
Delivery insurance documents to ESS for review (Rob)
Agree on SAT scope and procedure (Yogi, Morten)
Optimisation of tender packages (Yogi, Rob)
Monthly reporting (Paul)
Decision on HB installation tentatively before June 7 (Morten)
Share target spend profile with ESS (Rob)

16. Actions III
Plan for Stub mockup of HB stub and Spoke or DTL stub to test installation sequence, cooling, and cabling
Plan CDR before submitting tender circulator/load/arc detectors. Can be remote (John)
Plan CDR for the design of support structure to be held at ESS (John)

17. Thank you