LSS Review - RF System Installation: Status & Worries

1. LSS Review - RF O. Brunner on behalf of the RF group

2. Summary • UX45 – RUX45 Installation • Status & Worries  Interactions with LSS installation • ACS, ADT & APW Equipment Preparation Status • Conclusions

3. 3 RF systems in LSS4: ACS - ADT - APW ACS APW APWL – RF APWT - BI APW APWL – RF APWT - BI ADT ADT

4. UX45 – RUX45 Installation • Main activities: • Water cooling • Civil Engineering • Cabling • Wave guide installation • Ventilation  Might affect the LSS installation if planning not respected By e.g.: UX45-RUX45 cabling=> WG installation => SC modules installation

5. Main worries – 1 (Civil Engineering) • Shielding wall in UX45 • Two passages used for QRL installation in the junction regions now being closed • Solution approved by SC/RP: Solid bricks • Problem: Non conform “bricks” used instead • “Solution” proposed by TS/CE: additional layer of bricks • Wall to be rebuilt? Waiting for SC/RP approval • Main worries: • Might affect LSS installation planning • Wall => Cabling => WG => SC modules • Personal protection during cavity commissioning • Equipment protection (cavity control system will be installed along the wall)

6. Main worries – 2 • RUX45 Roof • Roof needs to be partially closed (on each side) prior to SC modules installation: Roof  RUX45 air cooling units Cryogenic distribution lines to SC modules  (WG)  SC modules • In order to follow up the LSS installation planning (H. Gaillard): • Roof parts must be ready by beginning of May • Roof installation: mid-May • Ventilation: 8 wks (?) • Cryogenic lines installation 4 wks • SC Modules installation mid-July

7. ACS System Equipment • Equipment/Status: • 100kV/40A LEP Power Converters: • 3/4 already checked by AB/PO • 4 HV bunkers (UX45) + equipment (modulators, crowbars, ..): • equipment in preparation. Ready for installation this summer • 16 high RF power stations (UX45): • pre-installation in progress at CERN • wave guide system: • 60% already mounted. Waiting for end of cabling campaign • 4 SC modules (4 cavities each) + 1 spare module: • now being tested and prepared in SM18 • will be ready for installation mid-July (as planned) despite all tuning system problems UX45

8. ADT System Equipment(CERN – JINR collaboration) • Equipment/Status: • All 20 vacuum tanks and supports delivered to CERN • 19 tanks & all electrodes cleaned and leak tested • 18 kickers assembled (bake out finished by mid-April) • Ready for installation as planned (16 kickers needed by mid-July)

9. APWL – pick ups • Equipment/Status: • Prototype built & tested • One pick up installed in SPS (reference) • 6 LHC pick ups now being built: • Ready by mid-April • Calibration done by mid-May • Bake out finished by mid-June • Ready for installation: end of June • APWT? Built by BI. Late delivery might affect vacuum activities (bake out in particular)

10. Bakeout in LSS4 • SC cavities • Absorbtion on cold surface from neighbouring sectors (cryo-pumping) => Increased dynamic losses, multipactoring => Difficult reconditioning after warm-up In test stands we need 10E-7/ 10E-8 to operate, limited volume (cavity & cut off tubes) Need better in machine due to larger volume (10E-9..?) • Electronics: • Single event upsets SEUs from beam gas collisions are a concern • Effect proportional to vacuum: => With 10E-8 mbar we would have between 10 and 100 SEUs per year in all LLRF systems in UX45(Rough estimate) Bakeout essential !

11. Conclusions • UX45 & RUX45 Installation • Still many interdependent co-activities • RF Systems: • ACS modules should be ready on time despite many tuning problems discovered recently • ADT kickers: will be ready on time for installation • APW pick ups: will be ready on time for installation • APWT? If late will affect vacuum activities (bake out)