2. LIU-ABT systems: SPS B.Balhan, J.Borburgh, H.Day 20 th November 2015

3. Outline 20/11/2015 SPS ZS improvement LIU SPS3 ZSTF 1 st upgraded ZS Impedance Measurement results Design and construction strategy New Itrap Box dedicated talk G.Raffaele Design Budget Planning Conclusion

4. ZSTF Solenoid for e-cloud suppression Promising, need more tests to confirm before propose to use as a base line for LSS2 extraction line. 4 20/11/2015 SPS ZS improvement LIU SPS MD note : MD note : https://edms.cern.ch/document/1519435/1 The ZS solenoid appear effective at the ZSTF, with the scrubbing beam in the SPS. Effects can be observed with currents up to 25 A, corresponding to a solenoidal field of approx. 0.65 mT. The vacuum activity wasn’t fully suppressed, and the need to maintain a field in the main gap to see the effect still isn’t understood.

5. 1 st upgraded ZS 5 20/11/2015 SPS ZS improvement LIU SPS ready to be installed in LSS2 to replace ZS 4 during YETS Since we have to install it between existing MPs, extra cables are required if we like to profit from the additional pumping. DIC in preparation by VSC. Need to decide strategy with RF screen and solenoid. Hybrid solution, need no move BLM as well !!!

6. ZS and Pumping Module (actual, no screen) 6 20/11/2015 SPS ZS improvement LIU SPS

7. 7 ZS and Pumping Module with screen 20/11/2015 SPS ZS improvement LIU SPS

8. ZS with new interconnect 8 20/11/2015 SPS ZS improvement LIU SPS Remaining Cavities

9. ZS with new interconnect and updated screen 9 20/11/2015 SPS ZS improvement LIU SPS

10. ZS Impedance Measurements 10 20/11/2015 SPS ZS improvement LIU SPS Beam Impedance Measurement done by Hugo using wire installed on a spare ZS with simplified elliptical beam pipes (both ends). Insert and new elliptical beam pipe effectively suppress any longitudinal modes below 1.2GHz. Much better impedance performance longitudinally Need some feedback from Beam Impedance Team to validate the concept and use it as a base line.

11. 11 20/11/2015 SPS ZS improvement LIU SPS Design and construction strategy EN/MME Job created to start August, postponed for LIU priorities (started in November). Weekly meeting planned to monitor follow up BI part for interconnect still to organise Tank modifications being finalised at main workshop still this year (all 10 tanks modified) VSC qualification of first tank done. Construction of interconnects to be subcontracted via EN/MME Updated RF screen design still to be validated by impedance team.

12. EVM DescriptionZS improvement activities Budget codes 99249 20/11/2015 SPS ZS improvement LIU SPS Year 2013201420152016201720182019 PV 803819240321010077 EV 8038171 AC 8038158 Metrics per year in kCHFCumulative metrics per year in kCHF Year 2013201420152016201720182019 PV 8011831071392310231100 EV 80118189 AC 80118277

13. Planning 1/yr tank to be assembled; by LS2 5 tanks ready 1 st tank may already be installed during this YETS Interconnects to be designed 2016, built in 2017 Purchase of vacuum equipment during continues for 2 tanks/yr (spares) Resources available: 0.5 FTE cp B (2015 – 2017) 0.25 FTE cp C (2015 – 2019) 0.25 FTE cp D (2015 – 2018) Missing: cp B/C 0.5 (2018 – 2019) 13 20/11/2015 SPS ZS improvement LIU SPS

14. Conclusions Concept design finished. Impedance approach validated with lab tests. To be endorsed by SPS study group. First upgraded tank successfully tested (HV as well as vacuum). Budget looks reasonable so far. Lacking technician from 2018 onwards. 14 20/11/2015 SPS ZS improvement LIU SPS

15. THANK YOU FOR YOUR ATTENTION!

16. ZS Beam Coupling Impedance Measurements Old Design: -BI/Pumping Modules had large beam pipe – cavity modes had large volume in which to exist – low frequencies -Ion trap isolated – whole ZS vacuum tank visible to beam – Many cavity modes New Design: -Pumping modules replaced with elliptical beam pipe with smaller aperture -Screen/insert placed at opening of ZS vacuum tank screening it from the beam -Addition of insert suppresses many low frequency cavity modes. Does create a large new one at 1.38GHz -Insert and new elliptical beam pipe effectively suppress any longitudinal modes below 1.2GHz. Much better impedance performance longitudinally H.Alistair