Commissioning Strategies for ELETTRA 2.0

1. Commissioning strategies and plans for ELETTRA 2.0Emanuel Karantzoulis • Outline: • Introduction • History • The upgrade • Commissioning requirements • Conclusions

2. Elettra - Sincrotrone Trieste, Italy: 2 complementary Light Sources FERMI: seeded FEL (4-20-100 nm ) open to users since 2012 (FEL1) and 2015 (FEL2) Elettra: open to users since 1994

3. Elettra • Third generation light source (DBA lattice, 12 fold symmetry ) , commissioned in October 1993 and open to external users since 1994. First 3rd generation in Europe for “soft” x-rays. Linac +Booster (114 m) Elettra was designed for 1.5 GeV 400 mA and 2 GeV 200 mA. Used a linac as injector that did not achieve 1.5 GeV therefore the machine was injecting at 1 GeV and ramping to 2 GeV until 2008 when a booster enabled full energy injection. In 2010 was established top-up. Storage Ring (259 m) • Operating modes for users (all in top-up since 2010): • Operates for about 6400 hours per year (24h, 7/7 ), 5016 hours reserved for users in 2 energies: • 2.0 GeV, 7 nmrad, 310 mA for 75 % of users time • 2.4 GeV, 10 nmrad, 160 mA for 25 % of users time • 28 operating beam lines – over 1000 user and user poposals / year • Filling patterns: multi-bunch 95 % filling or hybrid, single bunch, few bunches or other multi-bunch fillings

4. Elettra CommissioningSome history Remembering the past may prevent from making the same mistakes in the future • At 1993 the “old guys” were terrorized in the event that no beam will be accumulated leading to a disaster. This because the “third generation” was considered a “difficult” machine and Elettra was the first of its energy range in Europe • We “young guys” were quite confident because: • The machine optics was well done with large dynamic aperture • We were well trained: wrote a series of HLS programs and tested them in an Elettra “simulator” • Controlled magnets, their measurements and made shuffling • Controlled all connections and polarities. • We were very enthusiastic and commission 24/24 7/7

5. History Real commissioning started on 5/10/1993 6.10.1993 8.10.1993 5.10.1993

7. 23 Ah 6 h lft Stored current indicates the ‘health’ of the machine

8. Tools and problems Beginning: We were based on FLS screens, tune measurment and orbit position monitors. BPM system did not have first turn available Tools: optics measurements, orbit correction, tune (both integer and fractional) Harware commissioned at the same time sometimes with problems Problems: All sorts Many rf- trips Many vaccum trips Suffered from linac (injector ) trips, that did not reach the designed at that timeenergy of 1.5 GeV Nevetheless the commissioning went very fast because the optics was good and correct (magnets )

9. Elettra upgrade-requirements • Operating energy 2.0 and 2.4 GeV • Keep the same building and the same ring circumference • Emittance: to be reduced by more than 1 order of magnitude • Increase the slots available for insertion devices • New microspot in-vacuum undulator beamlines need to go on long straight sections • Leave open the possibility for installing bunch compression scheme • Include superbends • Keep the present injection scheme and injector complex • Preserve the present intensities and the time structure of the beam • Minimize the downtime for installation and commissioning to about 18 months or less ( ~14 months for the machine)

10. S6BA-E Emittance 130 pm-rad (79 if round beam ) @ 2 GeV or 190 (115 ) pm-rad at 2.4 GeV – Can go as low as 98 pm flat beam at 2 GeV Short bunches of about 1 ps rms possible due to alpha adjustment scheme (S6BA-EM)

11. Elettra 2.0 Lattice in the tunnel Best configuration up to now, satisfying all requirements, including the free space for IDs is based on our special six-bend achromat (S6BA). Elettra Elettra 2.0 A preliminary but complete Conceptual Design Report was produced in January 2017 (https://www.elettra.eu/lightsources/elettra/elettra-2-0.html?showall= )

12. Schedule (from CDR) BUT Alternative schedule is needed to follow the real cash flow, this may shift the date of operation for users by about 2.5 years

13. Schedule modified to follow the cash flow

14. Machine Upgrade • The machine upgrade except all other problems has also the pressure from users in many ways • Convince the users and beam line scientists on the necessity of the upgrade is not always easy. • Management requires dark time reduction. • Machine commissioning under great pressure (psychological factor not to be undervalued) • vs. Green Field • Instead in a Green field machine everything is easier. • No users to convince • Commissioning is very relaxed since no users are waiting

15. Preparatory work • To install Elettra 2.0 one must first dismantle the old machine. According to the schedule both tasks should be performed within one year • The available time for dismantling the present machine is 4 months (total 216 days but part of it coincides with installations). Therefore, the proposed plan is to empty three cells per month using the existing cranes. • Upon arrival, the new hardware will be stored in the already indicated storage area. From there the magnets will be moved to the magnet measurement hall (if it is decided to do this task on site, otherwise magnets will be measured and accepted at the factory). The vacuum chambers will be sent to the vacuum hall for inspection and (if needed) cleaning. All hardware will then be moved to the assembly area to be preassembled on the girders. To optimize the procedure, the preassembly process will start in advance (i.e. before dismantling). The alignment of the magnets will be done via wire on the girder. • Four girders for each section are foreseen. There are two cranes of 7.5 ton capacity each to transport the preassembled hardware on the girders into the ring for installation. It is reasonable to assume that one section per week can be installed.

16. Commissioning Requirements • The restart of the new storage ring will rely heavily on existing laboratory expertise and infrastructure. All hardware and software must be fully integrated into the control system so that procedures can be tested well in advance of the restart. • The initial objective is to store a low intensity beam of only a few mA to be able to optimize the lattice and to commission all new hardware and software. Depending on the progress, a large amount of time will then be devoted to the vacuum conditioning. According to our experience at least 100Ah of beam will be needed to obtain a good vacuum. For the beam-line commissioning the intensity will depend on the vacuum and radiation levels; beam might be delivered at reduced current for some time. • During the last three-month period a parallel commissioning of the machine and the beam-lines is foreseen. That period can also serve as buffer time to further optimize the ring performance, for hardware interventions and to reach user service mode conditions.

17. Some important facts • All agree on the importance of the magnet quality and measurements as well as alignment. For the magnet alignment on the girder we will use the wire method ( accuracy of about 15 micron rms) • All protection systems must be in place and operational before restarting. Time will also be allocated to fully commission the interlock systems. All equipment must already be checked and be ready for the first injection attempts. • Needed systems and programs at the beginning: optics measurements (tunes, chromaticities etc. ), orbit measurements (first turn etc.) and a few FLSR • For the machine commissining a 3 months period is considered followed by a 4 months period for beam line commissioning

18. Summary The Elettra upgrade has been funded by the Italian Government. The funding profile will obviously determine scheduling. The S6BA-E is the closest to the various requirements for Elettra 2.0. However it is more demanding from the engineering point of view. There is a pressure to minimize the “dark time” including time for commissioning It appears that a 3 month time for commissioning is sufficient and including 11 months of installations the total “machine” dark time may be 14 months

19. Thank you for your attention