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

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

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

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

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)

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

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

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)

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)

Bakeout in LSS4 Bakeout essential ! SC cavities Electronics: 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 !

Conclusions UX45 & RUX45 Installation RF Systems: 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)