1. CDR for the ESS Linac Magnets for LWUs (pulsed quadrupoles and DC correctors) Closeout May 4, 2016 J.G. Weisend II, Chairman CDR

2. General Comments 4 May 20162 The committee was very impressed with hard work and level of detail of the design presented. The expertise and experience of Elettra in this area is impressive. In particular, the experience with both the Elettra Synchrotron and the Fermi FEL have been suitably applied. Performance and interface requirements are ( with only a few exceptions) are agreed upon, well understood and documented. The design is well developed and is judged to meet all the requirements There is very good communication between Elettra and ESS and a collaborative spirit exists. The possibility of eddy current heating of the vacuum system may be a significant problem and may impact the design of the LWU vacuum chambers. Testing to determine if this is a problem must be expedited. … LWU Magnets CDR - J.G. Weisend II

3. Decision 4 May 2016LWU Magnets CDR - J.G. Weisend II3 The committee finds that the design presented is sufficiently advanced and ready to move to procurement and manufacture for the yoke and associated structures The procurement and manufacture of the coils should wait until the results of the prototype tests are complete The planning for verification activities including testing, and the planning for quality assurance and control (QA/QC) needs to be better defined and documented prior to the awarding of contracts for procurement and manufacture of systems and components. In regards to QA/QC, Elettra should identify and apply relevant procedures from their ISO 9001-certified quality management system for procurement and ensure their sub- contractors do likewise for manufacture and for other contracted services and deliverables.

4. Charge Questions 4 May 20164 1.Has design and supporting activity for MAGNETS progressed and reached a level of technical maturity in accordance with the activities and milestones for this Work Unit recorded in the ESS ACCSYS Project and been documented sufficiently and presented in a suitable format to enable review at this CDR? Yes. Design has reached the level of technical maturity but planning for verification activities still needs further work. See recommendations. 2.Are all or a sufficient coverage of requirements and specifications for the MAGNETS, including for its interfaces with other systems, documented by ESS, communicated to and understood by the Work Unit team ? Yes, with a few minor exceptions 3.Does the design meet these requirements and specifications? Yes LWU Magnets CDR - J.G. Weisend II

5. Charge Questions (cont.) 4 May 20165 4.Have safety issues and technical risks been identified and eliminated or otherwise mitigated for in the detailed design or identified for managing for manufacture, assembly and installation ? Yes. There were no outstanding safety issues identified. They are referring to the Low Voltage Directive 2006/95/EC but this one has been repealed by the new directive 2014/35/EU in April 2016 and. Elettra shall use the updated one. 5.What quality assurance and quality control activities have been planned and how will these be conducted and documented or reported? See recommendation. Elettra will deliver a project quality plan addressing the headings and content of ESS-0037830 ESS template for Project Quality Plan, prior to contracting for procurement and manufacture. 6.Is there sufficient staff resources assigned to the Work Unit team by its parent Elettra to allow to progress with work in accordance with activities, durations and milestone dates shown in the ESS ACCSYS Project plan ? Yes, manufacturing staff at Elettra needs to be protected so as not to be moved to other projects. A more detailed staff plan should be produced. LWU Magnets CDR - J.G. Weisend II

6. Charge Questions (cont.) 4 May 20166 7.Is the design information and information on procedures required for the operation of the MAGNETS delivered and presented at CDR sufficient? (This includes operational modes and MAGNETS functionality including adjacent systems and interfaces) ? Generally Yes. Interfaces are well described and high level operating modes defined. Operating Procedures were not presented but final details depend on power convertor choices. 8.Are the strategy, policies and regulations for procurement, manufacture and assembly sufficiently identified, defined, documented and understood by the Work Unit team or its parent Elettra, including supplier source(s) and pre-procurement activities and progressed to a sufficient stage ? Yes LWU Magnets CDR - J.G. Weisend II

7. Charge Questions (cont.) 4 May 20167 9.Is the schedule for delivery of materials, components and for the manufacture of MAGNETS sufficiently understood and in accordance with activities, durations and milestone dates shown in the ESS ACCSYS project plan? (This includes the time schedule and technical risk evaluations) ? Yes. There are some minor disconnects with the STFC LWU schedule but these seem solvable and occur in 2018. The schedule has no float 10. Does the Work Unit team or its parent Elettra require additional input from ESS or its other partners, or seek additional review, decision or approval from ESS to proceed with all work planed? See recommendations. ESS will review and provide any recommendations for Elettra ‘s verification plan and Elettra’s quality plan prior to Elettra’s the contracting for procurement and manufacture. LWU Magnets CDR - J.G. Weisend II

8. Charge Questions (cont.) 4 May 20168 11.Are there any outstanding agreements to be made or other actions necessary to allow the work unit to achieve the Plan? Yes, the signing of the Elettra schedule must be completed by the end of May in order to maintain project schedule. All technical aspects of this schedule have been agreed upon. …. LWU Magnets CDR - J.G. Weisend II

9. Recommendations 4 May 20169 1.Conduct tests as soon as possible to see if the eddy current heating of the vacuum chamber is a real problem. This shall be done in two steps: 1) a fast test with a similar chamber say at CERN or with a dummy system at Lund University by Mid June (driven by the need for the LWU chamber production) to bench mark the model and 2) a final test with the final chamber and prototype magnet in august. The test prior to Mid June must be given highest priority. 2.ESS will define the impact of the beam losses if the corrector power supplies operate at 20 A rather than 16 A. This analysis may lead to changes in the MPS beam loss monitors. 3.ESS Beam physics should verify that the 3% difference in field possible in the corrector under certain conditions will not cause problems. 4.Fiducial targets shall be added to the correctors to allow alignment. Elettra should work with the ESS alignment team (F. Rey) and with STFC to address this topic. LWU Magnets CDR - J.G. Weisend II

10. Recommendations 4 May 201610 5.The ESS integration group should determine how best to run the power and interlock cables for the magnets within the tunnel. 6.Study the possible of using a flexible cable (that is fixed) rather than a solid bus bar to carry out the intercoil connections in the quadrupoles. 7.Thermal switches shall be radiation resistant. LWU Magnets CDR - J.G. Weisend II

11. Recommendations 4 May 201611 8.Elettra to deliver a verification plan, in Excel or other format, identifying tests and other verification activities such as analysis, inspection etc, verifying that as-built magnets meets all technical requirements. Please show dates and durations for these activities. Please include planning for: The tests identified in HoA technical annex chapter 4.1.3 (same in draft IKC Agreement Schedule (TA) chapters 4.1.3 and 4.1.4), and also Any other verification activities planned to verifying each and all technical requirements listed in magnet functional requirements and magnet interface requirements, References B and C to the draft IKC Agreement TA. 9.Elettra to deliver a quality plan for ESS linac magnets for LWUs, addressing the heading and contents identified in ESS-0037830 ESS template for Project Quality Plan. Elettra should make references to relevant procedures of Elettra’s ISO 9001 certified quality management system and describe their application for this particular project, including how these are applied in the work of sub-contractors in procurement and manufacture for magnet components and systems. LWU Magnets CDR - J.G. Weisend II

12. Recommendations 4 May 201612 8.Include Power Convertors, Magnets on the upcoming June LWU CDR 9.Improve Insulation between coils and ground and develop tests to verify performance 10.ESS shall come back with final requirements for the wiring of the thermal switches 11.Conduct an extensive thermal cycle test on the prototype coil 12.Test the field delay due to the eddy currents on the prototype at CERN. The availability of the prototype power convertor at CERN for this test would be helpful 13.Develop an integrated test for the presence of mechanical vibrations with the prototype magnet, power convertor and LWU magnet chamber with stands. Add other subsystems as possible. 14.Define polarity convention and a procedure to avoid mistakes LWU Magnets CDR - J.G. Weisend II

13. Two Final Comments The chair would like to thank the Elettra team for all their hard work in both carrying out the design and development as well as their preparation for the review The chair would also like to thank the committee members for their time and efforts in participating in this review 4 May 2016LWU Magnets CDR - J.G. Weisend II13