PS-LIU status S. Gilardoni – BE/ABP H. Damerau – BE/RF LIU-PT 27 Aug. 2015

Space-charge study (Same as last time) Validated by simulations that observed emittance blow up and losses are due to space-charge exciting 8 th order vertical structure resonance yp (AU) Y(AU)

Possible improvements on operational beams Applying to 25 ns operational beam improvements studies for HL-LHC era -Space charge limits maximum tune shift between vertical integer 6 and structure resonance 8Qv=50 -Reducing chromaticity improves the interaction between the resonances and the neck-tie -Reducing chromaticity reduce the rise time and the headtail mode number on the injection flat bottom → use of the T-damper instead of linear coupling. -Working point during acceleration kept always below 8Qv=50 Transverse emittance reduced in both planes -Not quoting absolute values on purpose …

Magnets activities : follow-up last meeting -Magnet status - 3 quadrupoles (design exists) for low beta insertion → Call for tender in September -Only 1 magnet needed in → still on good track - Magnet for IPM horizontal plane

RF systems (main systems) Longitudinal damper: work progressing as planned - This week and next week first tests of coupled-bunch damping - Tests also in view of Finemet review 10 MHz system: - Final amplifier prototype ready for installation on spare cavity in PS ring during YETS 2015/16 - Status review in September T-damper upgrade - Schedule still compatible with commissioning needs for power amplifiers. Review on resources available for this activity on hold to give priority to Firmware development (more urgent) - New firmware for 80 bunches scheme currently under test. Confirmed decision not to implement a third 40 MHz system (pending as option) -Preliminary MD results with SPS: even with both 40 MHz cavities and nominal longitudinal emittance, the minimum losses remain almost unchanged; minor increase of 40 MHz voltage not sufficient for relevant effect on PS-SPS transfer -Two 40 MHz cavities allow to transfer larger longitudinal emittance without compromising bunch length  can be studies this year -Solution preferred to eventually run with two 40 MHz cavities (today: one used, one hot spare) with nominal/increased voltage and improved reliability; operation in degraded mode with one cavity possible  Renovation project (consolidation) for new anode power supplies  Pros: less maintenance compared to three cavities

Power converters -Boost of PV during end 2015 beg for construction of power converters for low energy converters. Confirmed payments in october-november. -Investigations ongoing on SIS to protect low-energy quadrupoles once new power converters installed during YETS Full solution with a WIC cannot be implemented now. Planned during LS2 it might be implemented during first EYETS. - Preferred solution: thermocouples installed on small number of magnets (8) to trip eventually all the 40 PC. - During tests turned out that existing protection is not effective even for existing PC. -Converging on design PC for injection bumpers - Simulation shows that ripple and tracking errors specified for power converters should not induce an emittance blow-up - New MDs to validate simulations recently repeated. Good results.

TT2 consolidation TT2 consolidation will be included in PS-LIU as agreed with EPC - restricted kick-off meeting in August. - general kick-off meeting in Sep. Date still to be fixed. Activity does not include the consolidation of the magnets - consolidation requested but not approved (yet) Renovation of FTN (nTOF) power converters should also take place - power converters in the same building (269) - if not done, impacting on final cost for TT2 consolidation Included in the budget simplified CV solution for water station - CV will see with Michael for more expensive consolidation including reallocation of man power in case final solution will be implemented

TT2 magnets: example of consolidation needs

TT2 consolidation documents TT2 specifications: TT2 infrastructure works: Agreement: Documents will not be re-approved in the LIU chain because already approved for consolidation. ECR or different document needed for replacing BHZ377 nTOF budget request will be presented to consolidation. Eventually also this activity might be moved to PS-LIU.

TT2-FTA renovation budget

BI -IPM to be installed end of this year. - BI still trying to get the system installed by the end of the YETS Agreed that the magnet installation is independent from installation of IPM - Some concerns (but already known) on production schedule -Re-iteration done recently with BI -Other instruments needed for LS2 -Still to clarify where to find the 250 kCHF missing for the normal BLMs cabling. For sure +30 kCHF for supports of fast BLMs. - BI meeting today - Trying to clarify if the budget is final or not - DICs for fast done. Trying to get the cables installed during YETS2015. Eventually the detectors can be installed later. Not clear yet when DICs for slow BLMs (possibly outcome of the next review)

BLMs proposed installation LHC IC Diamond detector - Integration agreed with Geometers and Magnet experts after integration tests on spare magnets. -Survey during next TS and eventually YETS2015 to check every magnet before going to production -Installation would be possible during a TS

Some fast BLMs signals already operational Example: Application for MTE extraction 5 turns Losses due to kicker rise time on de-bunched beam

Vacuum -Design of new injection region vacuum chamber well advanced - ECR of vacuum chambers replacement in injection region will be presented soon - Difficult to have both MU41 and MU42 replaced during next YETS due to production schedule - MU41 vacuum chamber replacement is priority for YETS2015. MU42 can be done eventually next YETS (or EYETS) - Rest of the work as support for other groups

Field homogeneity on straight lines being optimized (ABT+ABP study) 16 SMH42 ∫B y dl homogeneity BMP42 ∫B y dl homogeneity -Field quality of injector bumper improved and now better than +-2% (pictures are from old design and above 2%) -Tracking studies will be done to validate influence of multipoles generate by SMH42, BWS42 and other bumpers

Injection kicker status Progresses seems to be promising. - Two solutions analised, one reusing improved existing kicker, second green field solution using available technology - Agreed with ABT to delay first presentation on status of the works by one month. - ABT plans to have MDs to validate model predicting the emittance blow-up for a given ripple on the kicker

Budget (as 25/08)