LIU-ION: Progress on the main WP activities with spending status S. Gilardoni Ack.: G. Bellodi, M. Bodendorfer, D. Manglunki, R. Scrivens, J. Uythoven

Few news on the project General indico web page (including L3 meetings): Project Meetings: - Every Thursday between 10:00 and 12:00 in B14 - Exact time might change to optimize attendance - Meeting split in two parts: -Core meeting -Machine specific subject with WP older and experts - Minutes available in the indico web page Linac3 study group meeting (led by Richard) - Usually once a month on Wednesday afternoon - Minutes available in the indico web page

WBS : defined as April 2015 (see.xls file) Main changes wrt original one (before restructure): -J. Jowett official contact for HL-LHC beam parameters -EVM coordinator : G. Bellodi - Explicit ABP support per machine: -C. Carli as Beam Dynamics WP older -RF structure expanded -Commissioner in charge per machine EVM : only missing is confirmation from RF

Clarification of the scope (pending confirmation from HL-LHC) Follow-up after C&S review: Possible running scenario after Alice upgrade as requested by ALICE (see ALICE LOI CERN-LHCC ): 2020 – Pb–Pb 2.85 nb – Pb–Pb 2.85 nb – pp reference run 2023,2024 – LS – Pb–Pb 2.85 nb – ½ Pb–Pb 1.5 nb-1 + ½ p–Pb 50 nb – Pb–Pb 2.85 nb-1

L3 activities Source : studies ongoing for finalizing implementation of bottle neck reduction after the source and before the solenoid. LEBT: -finalising the analysis of the data taken during the Ar run in comparison with simulation results. A report will be put together in the summer. -Pb beam simulations to compare the different solutions proposed for the LEBT upgrade -meeting beginning of June to review the results and take a decision on which option should be implemented by the end of the year. -Measurements with the Pb beam should start in mid-June Budget: EVM funds for 2015 (source and LEBT combined, 35+55k) will be used for the upgrade of the source extraction and LEBT. More precise costing should be available in a couple of weeks once a decision is taken on which extraction design will be adopted.

100 ms L3 operation and L3 schedule Quadrupoles Power converters and electronic control of dipole upgrades have been advanced to allow tests at 100 ms injection in LEIR already in Capacitor banks commercial unit available on the market with characteristics very close to this request. It has to be verified that : - it could be mounted in the power crate, - its performances correspond to specification, - the reliability of these units is correct FI investigating the purchase of the units, still on track for 2016 installation Ion complex should not start before March-April 2016 to allow installation of new source HW and upgrade to 100 ms operation of power converters. Source could start beginning of March and LEIR in April. - confirmation within a couple of weeks - we should have this approved by IEFC probably and included as soon as possible in Mike’s schedule and for OP resources. L3 will not be able to operate on stable mode at 100 ms because consolidation of cooling and ventilation planned for LS2. - Test of 100 ms operation will be anyhow possible already in 2016

L3 100 ms EPC upgrade planning To Be planned. Foreseen together with other upgrades in

LEIR -Intensity limitation studies progressing - With Ar dedicated MD - Simulations PTC-PyOrbit based on existing model -Follow-up of operational issues impacting also LIU studies - Chromaticity sign (polarity meas.) and sextupoles controls - Noise on power converters solved - Improving OASIS signal quality - Improved Timber logging - Summary of open issues and follow-up during Ar MD review - Automatic creation of magnetic cycle being follow-up by OP and CO -First meeting with C. Carli two weeks ago.

LEIR External dump planning and costs First integration study showed an issue for the vacuum chamber in the dipole close to the dump. Study ongoing to find solution.

LEIR Ar debriefing review Ar dedicated MDs after end FT physics run: Goal: use Ar to study Pb intensity limitations 5 days, Wed. April 8 th to Sun. April 12 th Extended run, short/no preparation time Thanks to everyone that made the MD possible THE only dedicated MD in 2015 Goal of the review: Synchronize information in LEIR team Disseminate knowledge to all participants Collect inspiration and ideas Discussions at the end about Pb run

LEIR Ar debriefing review Site of review : Draft Minutes available here: Preliminary list of Pb MDs and preliminary outcomes already presented at IEFC (22/06) by Django Future Pb schedule should mention dedicated MDs for the Linac3 every Monday and for LEIR every Wednesday (as for other injectors) Thursday/Friday: SPS setting up LEIR future studies (already included in run schedule, more detailed list in preparation): Exploration of tune diagram (resonances and space-charge) Chromaticity (space-charge, instabilities) Damper (controlled transverse emittance blow-up) RF capture (test of RF loops, relay gap closure, etc..) Electron cooler (faster cooling rate) Bare machine (dedicated)

Ar results impacting on Pb limit understanding -Increased e-cooler current bring to faster cooling rate (for 10 Hz oper.) - Study to understand maximum current and optimize electron beam shape -Machine can still accept sufficiently large intensity for chosen scheme - Cumulated Ar intensity before the RF capture at 9e10 charges -Losses appear during capture - Could be space-charge neck tie interacting with one of the resonance - Not possible to observe turn-by-turn PU data, will be for Pb to discard instability hp.

E-Cooler: Electron beam from 200mA to 335mA Time Momentum 200mA Injection Cooled and dragged beam

E-Cooler: Electron beam from 200mA to 335mA Time Momentum 335mA Cooled and dragged beam

Ar int. After optimizing inj. steering + cooling

After optimizing inj. steering + cooling As much as record electrical intensity with Pb 54+ in 2013!!

We can disentangle RF capt. and magn. ramp!

RF capture advanced by 400ms

Follow-up from C&S review specific to LEIR -Losses analysis - As for Pb, Ar show losses at capture and clearly disentangled from acceleration -Hp: Direct space-charge during capture, Transverse instability, RF loops -Actions: Induce T-emittance blow up, obtain turn-by-turn T-damper PU data, see new LLRF loops -Desorption hypothesis on loss influence: - Discussion done with VAC - Starting from vacuum pipe models simulation of desorption and vacuum bumps propagation

Schedule 2015 (presented at last IEFC) Source restarted 25/4 Linac commissioning 11/6 LEIR commissioning 25/6 PS commissioning 24/8 SPS commissioning 28/9 Pb to North area & LHC 15/11 21IEFC – April 10 th, 2015Ar debriefing - D.Manglunki (D.Küchler)

LEIR specific work planning (Ar+Pb)

SPS injection Outcome of C&S review: -100 ns injection in the SPS should be delayed since luminosity gain with that was not judged sufficient (+24% peak luminosity) -Preliminary (unofficial) HL-LHC analysis seems to indicate that the integrated luminosity gain with 100 ns injection kicker is towards 40% increase of the integrated luminosity - Still waiting for official beam parameter at LHC injection from HL-LHC

Current SPS 100 ns injection strategy As presented by Jan at last LIU-ION meeting (

SPS Slip stacking RF confirmed that: -Slip stacking in the SPS should work, with a final efficiency to better determined -Lack of manpower being assessed with RF group - First feedback from Philippe - Hofle (RF WU older) following this closely -Summary of first meeting available at LIU-core meeting 02/04 (

SPS: IBS at low energy First discussion on planning taking place now Probably first study on basics parameters (longit and transverse emittance) optimization based on simplified model to asses program for future studies Prepare program for simulations and MDs in SPS Eventually use a short MD cycle with only a short flat bottom and no acceleration to investigate first appearance of IBS traces and eventually prepare studies with multiple injections. Investigate “exotic schemes” to see if they make any sense (acceleration-deceleration between injections…)

General planning up to 2018

TDR status Still planning to have draft by end of June. New chapter will be put on the EDMS LIU structure as done for protons. Status: -Existing introduction will be trimmed depending on HL-LHC input -Source/L3: new version received from Richard. Now circulating for comments -LEIR : - reviewing if needed a specific section and adding text to introduction - External dump description -PS: Heiko/Steve will provide few pages on bunch splitting -SPS: - RF reviewed by Wolfgang Hofle (Slip-stacking and T-damper). - Ion injection: as agreed with Malika will be included explicitly mentioning that will be realized outside LIU (if needed) but with the design done in LIU and kept as option. Jan revising existing Functional specs and already well advanced.