MD Studies for LIU PS Injection M. Serluca, W. Bartmann, V. Forte, G. Sterbini MSWG, 02 September 2016

Motivation Optics studies on the transfer line and PS ring for the future injection at 2 GeV have shown that the optimized septum position is 1 cm closer to the PS closed orbit with respect the actual position MD goal: verify that the future septum position is compatible with LIU requirements for 2 GeV beams type and PPM compatibility with beam at 1.4 GeV

Present injection region SS42 ACEM BLM42 Diamond BLM42 Injection line from PSB MU 41 MU 42 BLMs on the top of MU42 BSW42 SMH42 BEAM

Future injection region Eddy current septum New septum-bumper 42 (same vacuum vessel) BEAM MU 41 MU 42 35 cm septum-like bumper

Future injection area Example of injection of 2 GeV HI beam with low beta insertion  Optics studies on the transfer line and ring have been carried out to optimise the horizontal position and angle of the septum and maximise the acceptance for LIU HI beams at 1.4 and 2 GeV. EDMS: 1557577 v.1.1 - PS-M-ES-0002 v.1.1  

Septum position and angle Future septum-bumper Blade thickness: 11 mm Present septum Blade thickness: 5 mm Present septum dr = 64 mm f = 10 mrad 62 cm 94 cm 1 cm Future septum dr = 54 mm f = 10 mrad

MD1740: setup and measurements Workflow from recorded data to final results MD data TIMBER: main parameters ( not all and some of them are saved for short time ) MATLAB, etc… : user scripts to save data during the MD ROOT, MATLAB, etc.. : user has to merge the data and use scripts to analyse them Generally data and scripts are not public Efforts are in progress to improve the process SWAN (Service for Web based Analysis): platform for interactive data analysis in the cloud SWAN is becoming widely used at CERN in combination of cernbox Interactive program environment: Jupyter Python-based applications: so-called notebooks Possibility to access and filter all data (TIMBER and MATLAB .m files) Generate plots inside the environment Create monolithic database, catalogues of analyses and encourage reproducible studies MD1740 Postprocessing.py notebook can be found in /afs/cern.ch/work/s/sterbini/public/2016/MD1740_SMH42

MD1740: setup and measurements TOF beam ex = 17.4 mm mrad el = 2.75 eV s t = 157 ns dp/p = 2.58 10-3 I = 800 1010 Knobs: septum: position, angle and strength kicker45 strength bumpers strength Recorded signals Beam trajectories BLMs along the ring BLM42 slow (yellow line) Fast Diamond BLM42

MD results: TOF beam

MD results: TOF beam First hour: 10 mins to take reference BLMs readings for nominal settings Test the septum motors

MD results: TOF beam Second hour: Test of the diamond BLM42 using the internal dump Optics optimization: reduction of the bump height and increase of kicker-septum strength

MD results: TOF beam Last hour: Automatized scan of SMH42 position and angle

MD results: TOF beam Scan of SMH42 positions and angles BLM42 reading for nominal position (64 mm) and angle (10 mrad) is 23 [8-bits ADC] Lower losses for position between 54 and 61 mm BLM42 8-bits ADC Scan of SMH42 positions and angles Same plot but with BLM42 reading filtered for data below 8 [8-bits ADC] Lower losses for position between 55 and 60 mm and angle between 8 and 13 mrad BLM42 8-bits ADC

MD results: TOF beam Previous results are confirmed by data from OASIS channels Diamond BLM42 Scan of SMH42 positions and angles Fast diamond BLM42 integrated values Lower losses for position between 54 and 60 mm Slow BLM42 Scan of SMH42 positions and angles Lower losses for position between 54 and 60 mm

MD results: SFTPRO beam SMH42 position and angle acquisitions Injection optics not optimized for SFTPRO beam BLMs show a slight reduction of losses

MD results: SFTPRO beam Scan of SMH42 positions and angles BLM42 reading for nominal position (64 mm) and angle (10 mrad) is 20 [8-bits ADC] Lower losses for position between 54 and 61 mm BLM42 8-bits ADC Scan of SMH42 positions and angles Same plot but with BLM42 reading filtered for data below 25 [8-bits ADC] Lower losses for position between 54 and 59 mm and angle between 8 and 13 mrad BLM42 8-bits ADC Similar results for AD and LHC beams

Conclusions MD results were very positive Septum position (around 56 mm instead of 64 mm) reduces the losses of a factor 3 for HI beams with the drawback of pushing the septum strength too close to its maximum value, i.e. reduced lifetime A lower position of the septum is also compatible with LIU requirements for 1.4 and 2 GeV beams