Presentation Transcript

1. Proposal for continuation of generic high power target studies Rob Edgecock (Huddersfield & STFC) on behalf of the UK High Power Target Group (UKHPT)
2. Outline Introduction Motivation for the proposal UKHPT WPs: - Motivation - External context Milestones Cost Conclusions
3. Introduction Our charge: propose generic high power target programme Used this as an opportunity: combine 4 separate target groups Unique in the world Broad range of skills and experience Apply to find solutions for important HP targets
4. High Power Targets WP1: Generic tools for high power target development and operation WP2: ISIS upgrades WP3: Thorium energy amplifiers (ADSR) WP4: Neutrino Factory solid target WP5: Low energy thermal neutron production WP6: Conventional neutrino and super-beams WP7:Muon to electron conversion experiments WP8: Generic fluidised powder target research
5. High Power Targets WP1:Generic tools for high power target development and operation WP2: ISIS upgrades WP3: Thorium energy amplifiers (ADSR) WP4: Neutrino Factory solid target WP5: Low energy thermal neutron production WP6: Conventional neutrino and super-beams WP7:Muon to electron conversion experiments WP8:Generic fluidised powder target research
6. High Power Targets WP1:Generic tools for high power target development and operation WP2: ISIS upgrades WP3: Thorium energy amplifiers (ADSR) WP4: Neutrino Factory solid target WP5:Low energy thermal neutron production WP6: Conventional neutrino and super-beams WP7:Muon to electron conversion experiments WP8:Generic fluidised powder target research
7. High Power Targets WP1:Generic tools for high power target development and operation WP2: ISIS upgrades WP3: Thorium energy amplifiers (ADSR) WP4: Neutrino Factory solid target WP5:Low energy thermal neutron production WP6:Conventional neutrino and super-beams WP7:Muon to electron conversion experiments WP8:Generic fluidised powder target research Note: Many of the HP target problems are common (generic). Broad range of skills are required to solve them. This proposal makes them available for each target. Not possible with individual proposals.
8. WP1: Generic Tools for High Power Targets Efficient, reliable and safe operation of high power targets requires: - thorough understanding of the target material operational limits - good real-time condition monitoring of the target Even more important for future higher power targets! Recent experience shows benefits of solid targets Need to assess true limits of solids: - R&D - measurements from existing targets, e.g. TS1, TS2, T2K Improved temperature measurement: - improved confidence in target condition monitoring - extended operating life for targets - reduced frequency of target replacement and disposal Monitoring of target and target cladding erosion: - erosion issues with cladding in high velocity coolant environment - careful control of target containment vessel atmosphere
9. WP1: Generic Tools for High Power Targets Aims: Develop tools based on new technology Better reliability and performance in extreme environments In particular: - Temperature measurement - Target structural integrity eg cladding condition - Heat transfer integrity - Erosion/corrosion of target and cladding - Long term strain measurement Maximum allowable temperature and thermal shock for solid targets Evaluation of erosion/corrosion rates of targets and cladding materials
10. WP2: ISIS Upgrades 180 MeVlinac: 0.5 MW 3.3 GeV ring: >1 MW 800 MeVlinac: ~5 MW Current focus: accelerators. Target(s) need work as well. Current idea: exploit developments elsewhere.
11. WP2: ISIS Upgrades UKHPT has much relevant expertise, e.g. - long term operation of tungsten target, inc. radiation damage - helium cooling - thermal shock - neutron production - moderation, etc
12. WP2: ISIS Upgrades Aims: Assess existing TS1 for operation at 0.5 MW and modifications required Contribute to ESS target activities: - Need to start soon as ESS moving “Pre-construction” to “Construction” - Limited discussion so far - Possibility of external funding in the future? Apply knowledge gained to ISIS Conceptual design for: - 1 MW - 5 MW
13. WP3: Thorium Energy Amplifiers Thorium as a nuclear fuel: - identified reserves would power the world for 10000 years - nuclear proliferation resistant (no Pu) - 0.6% of waste for storage cf Uranium - but..........sub-critical Make neutrons via spallation- Higher safety margins Accelerator requirements are tough: - >4 MW - 99.9% duty cycle due to thermal stress, power production Significant interest world-wide
14. WP3: Thorium Energy Amplifiers Aker Solutions (bought by Jacobs Engineering Group) ADTR Searching for partners – academic & industry, mainly UK In discussion with us re target and beam window
15. WP3: Thorium Energy Amplifiers Aims: Determine target and beam window requirements for ADTR Study: - Potential target materials - Solid vs liquid - Thermal shock issues - Whether more than one target feasible - Integration of target(s) within reactor - Neutron delivery to fuel - Operation of target(s) within reactor Produce conceptual target design Design for a target beam window
16. WP5: Low Energy Thermal Neutron Production Use compact, DC, possibly electrostatic, cheap accelerators to produce high flux of thermal neutrons commercially Li(p,n) looks attractive Possible applications: - BNCT - Moly99 production - Security Emphasis here on first two - Check whether third improved
17. WP5: Low Energy Thermal Neutron Production Boron Neutron Capture Therapy Very good for aggressive tumours, particularly infiltrating healthy tissue Complementary to other therapies Most studied: Glio-blastomamultiforme (GBM); kills 2000/year in UK 2 year survival: Current neutrons sources: test reactors For accelerators: - 5-10 mA DC - ~ 3 MeV - solid target Best currently: ~1 mA using Dynamitron (IBA) in Birmingham
18. WP5: Low Energy Thermal Neutron Production BNCT Aims: ”Proof-of-principle” project funded by STFC Implementation, testing and running for clinical trials Commercialisation: - Siemens ONIAC - IBA Dynamitron Modelling and tests: possible external funding Implementation in Birmingham(?)
19. WP5: Low Energy Thermal Neutron Production Moly Aims: 99Mo is used for 99mTc: used is 85% of medical tracer applications Current source: 5 reactors, all >40 years old; two recently off Possible to make via accelerators, but needs to be commercially viable Low energy (low cost!) option studied here: - 50-100 mA at 5 MeV - flowing lithium target Aims: - Determination of requirements - Modelling of neutron production, heat deposition and transfer - Neutron capture and delivery - Extraction of moly Possible external funding: NHS for - Moly extraction test in Bham - Prototype
20. WP4: Neutrino Factory Solid Target Baseline target: free mercury jet But: - selected in 2006 - much progress since then on solid option - trend away based on problems at 2 contained mercury targets - plus heat load.........
21. WP4: Neutrino Factory Solid Target Solid baseline option: tungsten Much progress: - sufficient yield strength, melting point, lifetime - radiation damage tested at ISIS Lower Z interesting to reduce neutron production and heat load But: - must be strong enough - have a high enough melting point - produce as many pions
22. WP4: Neutrino Factory Solid Target Aims: For W or ? - test bulk samples in HiRadMat at CERN - determine effect of radiation on strength - verify solid target change mechanism NB: shock test rig of interest to others and may become commercial facility
23. WP6: Conventional Neutrino and Super-Beams Recent indications from T2K and MINOS that sin22θ13 ≥ ~0.01 make long baseline SuperBeams a most attractive option for first searches for CP violation in the neutrino sector. UKHPT members were responsible for T2K target (PPARC grant funded), and design studies for LBNE target (FNAL funded) and CERN SPL-based SB target (FP7 funded). Request for participation in three possible next generation facilities: - LBNE at FNAL (0.7 – 2 MW) - LBNO in CERN (2 MW) - T2K upgrade in Japan (1.66 MW) Funding this research will give the UK increased leverage for wider access for UK physicists to whichever of these facilities is constructed.
24. WP6: Conventional Neutrino and Super-Beams Primary purpose: multi-strand SB target development programme: - Targets will be required to operate at limits of static and dynamic mechanical stresses, heat transfer and radiation damage. - Off-line testing of designs is required to check simulations and identify limits where simulations alone are insufficient. - On-line testing e.g. at the HiRadMat facility in CERN. Packed bed cannister with symmetrical transverse flow configuration
25. WP6: Conventional Neutrino and Super-Beams Aims: Specification of preferred candidate materials for targets and beam windows Specification of off-line tests required to determine material lifetimes Beam window design Operating limits for helium cooled graphite targets Detailed design of a beryllium target Detailed design of packed bed target using Ti or Be Determination of preferred target technology for each facility Generic conceptual design of SB target station Off-line heating and cooling tests
26. WP7: Muon to Electron Conversion Experiments UKHPT members have been asked to contribute to the target development for both the Mu2e and COMET experiments. Initial design work to the 10% level for CD-1 has been carried out under an Accord with Fermilab. The next stage will be the major work, and it is unlikely further funding from the US for a UK group will be forthcoming. UK funding for this work on Mu2e would be part of a wider collaboration on accelerator R&D between STFC and Fermilab, enhancing the scientific reputation of the UK in the US and increasing access to the facility for UK physicists. Contribution to COMET in this area would strengthen the roles of the Imperial College and UCL university groups already involved. It would seem likely that only one of these experiments would be built. Consequently this programme would be highly likely to be implemented in whichever experiment is constructed.
27. WP7: Muon to Electron Conversion Experiments COMET. Water cooled tungsten rod. 8 GeV, 56 kW. Detector Solenoid Spectrometer Solenoid radiation shield pion production target Muon Transport Solenoid Mu2e target station. Uses water cooled thin gold rod. Designed by RAL group. proton beam Pion Capture Solenoid
28. WP7: Muon to Electron Conversion Experiments Aims: Engineering design of production target. Design of production target support and integration system within solenoid. Engineering design of target handling, replacement and disposal system. Beam window/end cap design. Conceptual design of Target Station. Prototyping of target manufacture. Prototyping of target support and integration system.
29. WP8: Generic Fluidised Powder Target Research Generic flowing powder target research programme proposed for the highest power densities. Potential applications include a neutrino factory, muon collider, superbeam or spallation neutron source. Flowing powder targets are suggested to have the following potential attractions: Shock waves Powdered material is intrinsically damage proof No cavitation, splashing or jets as for liquids High power densities can be absorbed without material damage Shock waves constrained within material grains, c.f. sand bags used to absorb impact of bullets Heat transfer High heat transfer both within bulk material and with pipe walls - so the bed can dissipate high energy densities, high total power, and multiple beam pulses Quasi-liquid Target material continually reformed Can be pumped away, cooled externally & re-circulated Material easily replenished Other Can exclude moving parts from beam interaction area Low eddy currents i.e. low interaction with NF solenoid field Fluidised beds/jets are a mature technology Most issues of concern can be tested off-line -> experimental programme
30. 2 1 3 4 WP8: Generic Fluidised Powder Target Research Still images from video clips of tungsten power flowing from 1.2 m long x 2 cm diameter pipes Open jet Contained discontinuous dense phase Contained continuous dense phase 1. Suction / Lift 2. Load Hopper 3. Pressurise Hopper 4. Powder Ejection and Observation
31. WP8: Generic Fluidised Powder Target Research This new technology has already overcome initial scepticism in the community. However to maintain momentum and, for example, to become the baseline technology for a NF/MC, will require the following programme to be pursued: Optimise gas lift system Attempt to generate stable solid dense phase flow Investigate low-flow limit Carry out long term erosion tests and study mitigation Implement CW operation Develop diagnostics for monitoring and control Study heat transfer between pipe wall and powder Demonstrate magnetic fields/eddy currents are not a problem Use of high field solenoid? Investigate active powder handling issues (cf mercury?) Demonstrate interaction with pulsed proton beam does not cause a problem First experiment on HiRadMat facility at CERN planned for autumn Future experiment planned using LDV to measure dynamic response of pipe wall. This experiment would be carried out together with a packed bed sample. Study low Z target material (e.g. graphite powder) for a 4 MW SuperBeam
32. Costs FY 12/13 FY 13/14 FY 14/15 FY 15/16 Totals/£k
33. Milestones WP4 is 1 year (for IDS RDR); all others are 4 year Main deliverables are conceptual designs of targets and target stations
34. Conclusions Targets are increasingly becoming the limiting factor in future projects High power targets present significant challenges Target R&D and target station design require a broad range of skills In this proposal, we are: - bringing together 4 existing target groups with this broad range- thereby creating a unique group - developing generic tools for target design and operation - undertaking R&D on targets well beyond the state-of-the-art - creating collaborations with external groups from hospitals to industry - seeding external funding for further development Projects range from Particle Physics to STFC Grand Challenges All will benefit from the generic approach proposed here
35. High Power Target Issues Modelling of beam energy deposition Modelling of secondary particle production Modelling of target material response using FEA codes Target cooling or replacement Activation and radiation damage everywhere Thermal shock Target lifetime Particle capture, moderation and delivery Beam windows Target station design, inc. shielding, RH, licensing, etc Diagnostics in high radiation environments Demanding environmental and safety requirements
36. WP5: Low Energy Thermal Neutron Production Boron Neutron Capture Therapy
37. WP5: Low Energy Thermal Neutron Production Security Aims: Scanning cargo containers Shielded nuclear material Requirements: - 100% efficiency - diverse material - 1 minute/container - low error rate Aims: - Determine beam requirements - Assess above targets - Compare with other projects
38. WP4: Neutrino Factory Solid Target Solid baseline option: tungsten Much progress: - sufficient yield strength, melting point, lifetime - radiation damage tested at ISIS Lower Z interesting to reduce neutron production and heat load But: - must be strong enough - have a high enough melting point - produce as many pions