Cryo equipment strategy in the R2E context Juan Casas & Nikolaos Trikoupis CERN TE-CRG Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Overview Radiation-Hard instruments Radiation-tolerant electronics Most instruments suitable for the LHC environment However valve positioners not properly qualified About 1’400 installed in the tunnel Radiation-tolerant electronics Strategy to monitor an eventual degradation Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Hard: Valve positioner Issue Is it a radiation-Hard instrument? One valve positioner tested in Fraunhofer Co-60 gamma till 100 kGy during 12:31 hour Passive/no on-line monitoring => Failure at end of test Valve positioners are everywhere in the tunnel Most critical nearby DFBx 100 kGy is not that higher than worst areas!! Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Hard: Valve positioner Issue Estimated TID for P1-P5-P7: 2016 till Aug 7 Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Hard: Valve positioner Issue Passive TID monitoring since 13th Sept RadFETs installed in P1 & P5 To be measured during next TS (1st time) Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Hard: Valve positioner Issue Is it a radiation-Hard instrument? One valve positioner tested in Fraunhofer Co-60 gamma till 100 kGy during 12:31 hour => Failure at end of test Valve positioners are everywhere in the tunnel Most critical nearby DFBx 100 kGy is not that higher than worst areas!! Next steps: Set irradiation requirements TID? <= defined experimentally from LHC RadFETs Select appropriate irradiation area Prepare test set-up with on-line monitoring => determine TID withstand level Define operational strategy Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Hard: Other Instruments in LSS Qualified cryo-sensors: Temperature sensors, maximum test dose about 3 x 1014 n/cm2 Most CANNOT BE REPAIRED Pressure sensors: qualified in TCC2 No indication of radiation damage Instruments deemed rad-hard by construction/design Level gauges based in a superconducting wire Same technology as magnet Solenoid proportional valves Made of a coil & a magnetic plunger Electrical heaters: wire-wound or foil resistance …… Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Tol: Electronics The electronics deployed in the tunnel is designed by using individually qualified components to withstand the LHC tunnel environment. The electronics is installed in the: LHC tunnel along DS & ARC LHC protected areas for commercial equipment & LSS instruments Radiation effects on cryo electronics: SEU: observed in protected areas => end-2011 consolidated TID produce drift: is it observable? Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Rad-Tol: Electronics TID effects: Power consumption on crates from cell 9 to 14 in P1, P3, P5 & P7: Power monitored from time to time, but changes too small to not rule out thermal origin. Strategy during next period: Measure power consumption for individual cards In regions deemed critical On “high” radiation areas leave equipment to asses maximum TID withstand level If TID effects become non-negligible => exchange equipment => Shift equipment from low to high TID areas End of life may at the end be due not to radiation effects. WFIP comm: ~280 spare over 1086 installed Nevertheless a nanoFIP alternative is foreseen (later) Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG

Summary TID may be an issue for cryogenic valve actuators in P1 & P5 A radiation qualification campaign is critical to establish an operational strategy. The next steps are: Determine TID for test Evaluate radiation hardness Establish operational scenario that can be: Leave as is Periodical exchange Move sensitive equipment by a few meters (not so difficult) For rad-tol electronics there is no particular issue, most probably the end of life is independent of the TID. Cryo equipment strategy in the R2E context-2016 JCC-TE/CRG