By Martin Freer, Ben Phoenix and Stuart Green
The High Flux Accelerator-Driven Neutron Facility will support the study of neutron interactions in materials for the nuclear sector, ranging from fission to fusion. In particular, this facility will offer a broader programme relating to the understanding of neutron interactions with materials with applications extending to nuclear medicine and space.
Based at the University of Birmingham, this is the first UK neutron facility capable of providing fluxes for the characterisation of degradation of materials in the reactor periphery. The high flux proton/deuteron beam will create neutrons through the interaction with a high power target. It will also be the first UK facility to possess a dual beam ion facility capable of providing the necessary fluxes to easily simulate the damage incurred by highly irradiated components such as cladding in current generation plant or structural materials in Gen IV or fusion reactors.
The new irradiation capability of this facility will combine with the existing high-energy light-ion accelerator to create a single UK user irradiation facility. This will form the most intense accelerator driven neutron source worldwide.
For the University of Birmingham, this new facility will create a new international research capability, and an opportunity to collaborate on more programmes on a national and international scale and train a new generation of researchers in state-of-the-art techniques.
There are also opportunities to develop a wider community which draws in those interested in fundamental nuclear physics, cancer therapy (e.g. BNCT), development of high power targets and radiobiology.
The project is funded through the National Nuclear User Facility Scheme (NNUF).
The facility is designed around an accelerator produced by Neutron Therapeutics which will be housed in a purpose built underground bunker. The accelerator will accelerate a high intensity proton beam which is converted to neutrons using a rotating lithium target. The new facility will include:
- Accelerator maximum proton current and energy: >30mA DC / 2.6 MeV.
- 100kW beam dump for tuning at full beam current.
- Designed for continuous operation aiming for uptime > 95% between service intervals
- Initial guaranteed neutron yield > 2.5e13 primary neutrons
- Neutron target performance maintained for >25 hours at full power with <10% yield loss.
Progress to date
The scheme achieved planning approval from Birmingham City Council on 22nd May 2020. Work commenced on site in September 2020. The excavation adjacent to the existing accelerator building for the new accelerator bunker is close to complete (see photograph) which has involved removal of the sandstone bedrock. The installation of the formwork for the building will commence shortly. The building will be complete Summer 2021 with the installation and commissioning of the accelerator then proceeding up to the end of the year. The facility will become operational early 2022.
Experimental program
The work to develop experimental end stations on the facility for neutron irradiation is now being started and the team would welcome input to help define those stations. There is a need to start to develop an experimental programme for the facility. This includes the existing MC40 cyclotron and the newly constructed High Flux Accelerator-Driven Neutron Facility. Please contact M.Freer@bham.ac.uk for discussions. Please also note that there is a national access funding programme for NNUF facilities, details are available via the NNUF website.