Future Work Plan and Action Items Jim Clarke ASTeC & Cockcroft Institute Daresbury Laboratory 16/7/10 DESY Positron Workshop

Actions from DESY Workshop Actions were placed on many groups at the DESY Workshop (Jul 2010) Short Term (Dec 2010) Medium Term (Mar 2011) Longer Term (end 2011) General comments/outstanding items Positron Workshop

Undulator Continue “Real” Undulator spectrums modelling of multiple 2m undulators – David Impact of random angular errors inside undulators – spot size on target, polarisation loss? Include quad misalignment – ANL Complete 4m cryomodule & test (fix heat load problem!) – RAL Horizontal magnet measurements required at some stage??? Electron beam tests required at some stage Modules need to be engineered for large scale production and operation Intermodule connections need engineering Store cryomodule safely so can be powered at a later date 3

Source Modelling Use real spectrum in PPS-Sim – Mike/Ian (assistance from DESY?) Generate lattice for source to DR - ? Supply period vs K for Nb3Sn undulator – RAL Assess impact of Nb3Sn undulator - Wei Look at PTRAN losses in ANL simulations with new lattice – Wei Ongoing list of current simulation codes and objectives + input files – Ian Ongoing yield/polarisation evaluation with source design evolution (Wei) 4

Compton Continue DR stacking studies and work with DR group to ensure optimum solution - Frank cavity stability tests (LAL/KEK) - Omori Laser demonstration – Fabian Zomer, Vitaly ATF demo with 4 mirror system – Omori 2010/11 demo with new cavities of high gamma flux at ATF 5

Polarisation Polarisation change with collimator aperture/beam position jitter (0.5 sigma jitter in electron position and angle) - ANL Close contact with IP group polarimeter (Tony) Ensure spin survives to DR Close contact with simulations group – spin track to IP Confirm investigation showing we can destroy polarisation in DR completely Electron spin survival within undulator – Des Study performance of spin rotator design, jitter effects etc (5GeV) 6

Collimation High power photon collimator needs to be studied Positron collimation – design documented, needs updating as source evolves Variable aperture collimator needed for polarisation upgrade (Electron collimation before undulator – BDS group?) 7

Target Complete Eddy current tests at Daresbury – Ian Store target properly – Ian/Jim Generate simulations to compare with experimental results – (Jeff/Tom) Ian/RAL Measuring conductivity of target material - Mike Pressure shock wave analysis – Stephan to pass on all files to Ian/Sabine (wiki) and write up/document and numerical modelling later Energy compression before DR to be studied to improve yield – Wan Ming Vacuum seal & water union tests – LLNL Ferrofluid radiation tests Beam tests on Ti (also W) samples (~100J/g) – ANL/LLNL/DESY/Ian to check what beam is suitable and make appropriate proposal (also 250 GeV beam collimators) Lifetime studies of target (LLNL) Alternative liquid metal & window (BINP/KEK tests) – Junji Engineered solution, including prototype tests – water, vacuum, … 8

OMD Li Lens - Cornell Evaluate level of radiation damage in window & implications for lifetime Stress-strain in window with liquid flow Thermal cycling fatigue Cavitation wear on windows Proton beam tests? Assess KEKB BN window tests - Omori Discuss funding with M Harrison – Marc/Nick Concern with liquid li containment in steel (Pavel) Flux Concentrator Complete design – LLNL Build prototype 9

Remote Handling RH scenarios refined Changeover times (requirement ties in with lifetime of kit in RH) Replacement of pillow seals? Pillow seals need R&D Need engineered design compatible with source layout (remove inconsistencies!) If yield increases then RH not needed (limited only?) Use detailed target, RF, etc model in Fluka 10

EDMS work package Report back on EDMS status – ongoing action Ian/Lars Put instructions on the wiki - Ian Use the wiki instead! 11

Auxiliary Source Is electron beam dump ok for AS? How to separate electron drive beam? Where do particles get lost? Intensity requirements vs BPM resolution How many bunches are needed ? Nick says Aim for 5% intensity 12

10 Hz Source Check cooling system of target – LLNL/ANL Put holes in target to let unwanted gamma beam through? Assess other options? Generate consistent layout showing extra electron dump, drive beam line to dump etc

Thanks to Gudi and Sabine for organising this workshop Thanks to you all for participating!