UKHPT Proposal for continuation of generic high power target studies Rob Edgecock (Huddersfield & STFC) on behalf of the UK High Power Target Group (UKHPT)

UKHPT Outline  Introduction  Reminder: motivation for the proposal  UKHPT  WPs: - Summary - What we think is to be funded  Costs  Conclusions

UKHPT Introduction  Our charge: propose generic high power target programme  Used this as an opportunity: combine 4 separate target groups GroupMain recent activities HPTG Technology DepartmentT2K, Super-beams, muon production, powder targets Huddersfield GroupADSR, ESS, muon production ISIS GroupTS1, TS2 UKNF Target GroupNeutrino Factory, thermal neutrons  Unique in the world  Broad range of skills and experience  Apply to find solutions for important HP targets

UKHPT 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, fatigue  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

UKHPT 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

UKHPT 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

UKHPT 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

UKHPT 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.

UKHPT 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

UKHPT High Power Targets  WP1: Generic tools for high power target development and operation  WP2: ISIS upgrades  WP3: Thorium energy amplifiers (ADSR)  WP5: Low energy thermal neutron production  WP8: Generic fluidised powder target research Moly99 only Start early Delayed

UKHPT 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

UKHPT WP1: Generic Tools for High Power Targets  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 Aims:

UKHPT WP2: ISIS Upgrades (1)180 MeV linac: 0.5 MW (2)3.3 GeV ring: >1 MW (3)800 MeV linac: ~5 MW Current focus: accelerators. Target(s) need work as well. Current idea: exploit developments elsewhere.

UKHPT 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

UKHPT WP2: ISIS Upgrades  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 Aims:

UKHPT WP3: Thorium Energy Amplifiers  Thorium as a nuclear fuel: - identified reserves would power the world for 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 % duty cycle due to thermal stress, power production  Significant interest world-wide

UKHPT 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

UKHPT WP3: Thorium Energy Amplifiers  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 Aims:

UKHPT 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

UKHPT 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 PoP underway

UKHPT 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-blastoma multiforme (GBM); kills 2000/year in UK  2 year survival: RadiotherapyRadiotherapy + TemozolomideBNCT + Radiotherapy 10.4%26.5%45.7%  Current neutrons sources: test reactors  For accelerators: mA DC - ~ 3 MeV - solid target  Best currently: ~1 mA using Dynamitron (IBA) in Birmingham

UKHPT WP5: Low Energy Thermal Neutron Production  ”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(?) BNCT Aims:

UKHPT WP5: Low Energy Thermal Neutron Production  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: 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 Moly Aims:

UKHPT 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

UKHPT 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 Suction / Lift 2. Load Hopper 3. Pressurise Hopper 4. Powder Ejection and Observation Open jet Contained discontinuous dense phase Contained continuous dense phase

UKHPT 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

UKHPT Costs FY 12/13FY 13/14FY 14/15FY 15/16Totals/£k WP1 University grants STFC Non staff Sub total WP2 University grants STFC Non staff Sub total WP8 University grants STFC Non staff Sub total WP3 University grants STFC Non staff Sub total WP5 University grants STFC Non staff Sub total TOTAL

UKHPT Conclusions  Targets are increasingly becoming the limiting factor in future projects  High power targets present significant challenges  They tend to be neglected, particularly in UK  Target R&D and target station design require a broad range of skills  Somewhat different from other accelerator R&D  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