2. Elettra – Sincrotrone Trieste S.C.p.A.
REPORT FROM ELETTRA SINCROTRONE TRIESTE ESS ACCELERATOR COLLABORATION BOARD MEETING Daresbury, February 1,2017
Alessandro Fabris
Elettra – Sincrotrone Trieste S.C.p.A.

3. OVERVIEW Elettra in-kind contributions for the accelerator:
AIK2.1
Magnets for ESS linac
AIK7.4
Beam Diagnostics- Wire Acquisition System for the ESS linac
AIK8.5
Spoke RF Power Station
AIK17.2
Power Converters for Magnets to the ESS linac
tbd
Installations
AIK2.1, AIK7.4, AIK8.5, AIK17.2 endorsed at IKRC 10 in October 2016.

4. REVIEWS Reviews in 2016 April12-13 PDR Spoke cavity RF power stations
May 4
CDR
Q5, Q6, Q7 magnets
C5, C6 magnets
May 17
C5, C6 power converters
May 18
PDR-1
Q5, Q6, Q7 power converters
June 28
Diagnostics - SEM system
Dec. 12
Diagnostics - Scintillator system
Next reviews in 2017:
PDR-2 Q5, Q6,Q7 power converters
CDR D1, Q8, C8 magnets
PDR D1, Q8, C8 magnets power converters
CDR wire scanners
Remaining CDRs to be done with manufacturers

5. SPOKE CAVITIES RF POWER STATIONS
Scope: build twenty-six pulsed 400 MHz RF power stations for the spoke cavities
C. Pasotti
Based on combination of two 200 kW tetrodes.
Each RFPS unit consists of:
Two equivalent transmitters with amplification chain composed by solid state preamplifier and tetrode amplifier.
One Modulator to supply both tetrodes.
Construction will be outsourced to industry under Elettra supervision.

6. SPOKE CAVITIES RF POWER STATIONS
Baseline: tetrode TH 595 with input circuit TH 18595A.
Designed for 200 kW pulsed operation at the ESS RF pulse requirements.
In operation at FREIA test stand.
Technical challenges
RoE with the chosen tetrode in other facilities, as FREIA, should allow to mitigate risk in the design.
AC line flicker and harmonic content due to the pulse operation should be taken into account in the modulator design.
First RFPS unit will be extensively tested to fully evaluate compliance to requirements and implement modifications if necessary.
C. Pasotti
OUTLOOK
Working with ESS RF group to optimise and freeze technical specifications in terms of performance, costs and schedule.
Writing technical specifications for tender. Final version of document by end February 2017.

7. MAGNETS
Scope: design and build magnets installed in different parts of the ESS linac
Activities concentrated on LWU magnets (Q5, Q6, Q7 and C5, C6).
Design for quadrupoles updated following switch to dc magnets
D. Castronovo Q6 Q7 C5 C6 Q5

8. MAGNETS LWU quadrupole magnet prototype under construction at CERN
Courtesy of D. Lopez, CERN
OUTLOOK
Prototype of quadrupole magnets to be tested at CERN by mid February.
LWU magnets technical documentation update reviewed.
LWU magnets technical specifications for tender available.

9. POWER CONVERTERS
Scope: design and build power converters for the magnets of the ESS linac
Bipolars
Type
Description
Operating mode
Q.ty
PCC5
Power converters for the “C5” dual- plane correctors
4Q, air cooled 26
PCC6
Power converters for the “C6” dual- plane correctors
110
PCC8
Power converter for the “C8” dual- plane correctors 8
R. Visintini
STATUS
Correctors power converters based on compact Elettra design approved in CDR.
Finalization of design for industrial production (Built-to-Print Call for Tender) in progress, according to ESS requirements. 9

10. POWER CONVERTERS
Type
Description
Operating mode
Q.ty
Note
PCQ5
Power converters for the “Q5” quadrupoles
DC, water cooled 26
Magnet defined
PCQ6
Power converters for the “Q6” quadrupoles 95
PCQ7
Power converters for the “Q7” quadrupoles 12
PCD1
Power converters for the “D1” dipoles 1
Magnet not yet defined
PCQ8
Power converters for the “Q8” quadrupoles 6
PCC8
Power converter for the “C8” dual-plane correctors
4Q, air cooled 8
Magnet not yet defined, design will be compatible with other corrector PC
R. Visintini
STATUS
In June 2016 ESS decided to pass from “Pulsed” to “DC” (PCQ5, PCQ6, PCQ7).
Completed the re-definition of PS following the changes in the Q5, Q6, Q7 magnets.
Preliminary recognition of potentially available PC on market.
Technical documentation for Call for Tender (subject to PDR-2) almost ready.
PDR-2 for DC quadrupoles power converters expected soon.

11. Scope: Wire scanner (WS) acquisition system design
BEAM DIAGNOSTICS
Scope: Wire scanner (WS) acquisition system design
Analog Front End Prototype
Design and Fabrication
Conditions:
50uSec Pulse; 0.5uA
GAIN =HI; Cable = 1m RG174
M Ferianis, R. De Monte,
S. Cleva, S. Grulja
Optical Front End Prototype
Design and Fabrication

12. BEAM DIAGNOSTICS OUTLOOK
WS acquisition system simulator
M Ferianis, R. De Monte,
S. Cleva, S. Grulja
OUTLOOK
After the preliminary design phase, detailed design is in progress
Testing of the prototype, before CDR, will be carried out in two main steps: in house at E-ST and at a partner lab to have access at signals from wires.

13. SUMMARY TA endorsed by IKRC (“Cover Pages”).
Working to complete remaining PDRs and CDRs, freeze technical specification and have technical documentation ready for when big procurement can start.
Working to clear administrative/legal aspects that prevent signing of IKAs and Schedules.
These actions involve as well INFN (Representing Entity for Italy in European Spallation Source ERIC) and ESS and the resolution is a prerequisite for the start of tendering phase.