Senior Research Fellow

As part of our Fusion Science for Clean Energy program at Nanyang Technological University, Singapore, we have an opening for a Senior Research Fellow to undertake experimental gamma-ray spectroscopy measurements on Runaway Electron (RE) beams at the WEST tokamak, which has a full tungsten first wall and divertor configuration with superconducting magnets. Gamma-ray emissions from fusion plasmas occur either due to relativistic runaway electrons born in disruptions, or to nuclear reactions involving fast ions. For example, fast alpha-particles emitted from DT reactions cause ⁹Be(α,n+γ)¹²C reactions producing Eγ = 4.4 MeV gamma-rays. At WEST, the RE beam current can be several 100 kA with electron energies up to about 25 MeV. These RE beams produce intense gamma-ray emission via bremsstrahlung scattering in the plasma and tungsten wall. A GRS system based on large-volume LaBr3(Ce) scintillation detectors with digital pulse processing is being developed to cope with high count-rates and a wide range of gamma-ray energies Eγ = 2 to 20 MeV produced by runaway electron bremsstrahlung. LaBr3(Ce) detector response to both gamma-rays and neutrons will be studied by Monte Carlo simulation using MCNP6 or GEANT4. The Senior Research Fellow will split their time between two locations. Part of their time will be spent at NTU in Singapore, developing and testing GRS diagnostics, performing simulations and data analysis. Part of their time will be spent at Cadarache, France, fielding the GRS diagnostics and participating in experimental campaigns on the WEST tokamak.

Gamma-Ray Spectroscopy (GRS) diagnostics are of expanding importance for tokamaks as runaway electron beams carry a large amount of energy, which represent a risk of damage to the machine. This risk increases as the size of machine increases, so the importance of gamma-ray diagnostics will continue to develop over the coming decades as the size of fusion devices increases.

Requirements for Senior Research Fellow Position

• Experience developing gamma-ray, neutron or charged-particle scintillation detectors
• Experience with modern scintillators like LaBr3(Ce), CeBr3, YAP(Ce), LYSO, or CLYC
• Knowledge of nuclear electronics
• Knowledge of digital pulse processing for radiation detectors
• Experience performing Monte Carlo simulations using MCNP or GEANT4 is desirable
• Have preferably three years of relevant experience beyond PhD in physics, nuclear engineering, or a related field
• Have excellent English written and verbal communication skills
• Have good organizational skills
• Able to travel internationally, especially between Singapore and France

Responsibilities

• Work on development of Gamma Ray Spectroscopy (GRS) diagnostics
• Perform GRS measurements during WEST experimental campaigns
• Perform Monte Carlo simulations using GEANT4 or MCNP
• Analyze GRS data to obtain the Runaway Electron energy spectra
• Contribute substantially to publication of GRS experimental results
• Assist with project management: from procurement of equipment and consumable to report writing