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Reference : UMR7588-IANVIC-001
Workplace : PARIS
Date of publication : Friday, September 11, 2020
Type of Contract : FTC Scientist
Contract Period : 15 months
Expected date of employment : 2 November 2020
Proportion of work : Full time
Remuneration : between 2728 and 3146 € gross monthly, according to experience
Desired level of education : PhD
Experience required : 1 to 4 years
We are looking for M/F post-doctoral scientist to participate in the development of a system to detect and map characteristic soft Xrays emitted by a solid under MeV proton irradiation (Particle Induced Xray Emission PIXE).
One of the constraints in detecting proton-beam induced soft (<~1keV)Xrays with a semiconductor detector is the need to stop elastically scattered MeV protons from entering the detector. This is usually accomplished by placing a low Z filter (for example Be) in front of the detector, sufficiently thick to stop the protons, but sufficiently thin to limit attenuation of the proton-induced Xrays. However any such filters always completely eliminate the low energy (<1 keV) soft Xrays. An alternative is to use a magnetic deflector in front of the Xray detector. The project concerns the design and implementation of a magnetic filter based on a micropore filter which will allow PIXE of soft Xrays. The micropore filter will also enable mapping of the soft Xrays with an Xray camera (Andor IKON-M). The system will thus open the way for PIXE mapping of characteristic Xrays from light elements such as carbon, nitrogen, oxygen, with applications envisaged in geology, materials science, cultural heritage materials or biology. The proposed work includes the design and building of the system, and also the detailed interpretation of the Xray spectra obtained, and the imaging properties of the system for light elements.
- High level of knowledge of particle-matter interactions, with knowledge of the physics of the emission of Xrays from solid targets bombarded by MeV protons beams desirable.
- Practical experience in the detection of Xrays with semiconductor detectors
- Independence, organisational and reporting capabilities
- Ability to adapt, be creative, learn, and develop new skills
- Basic knowledge in computer programming with a common language such as Python, C++, Delphi, Fortran …
Within the RADIATE (https://www.ionbeamcenters.eu/radiate/) EU project, INSP proposes to develop soft PIXE imaging capability, and is recruiting a post-doctoral researcher as part of that program. As part of the INSP, a mixed CNRS / Sorbonne University research unit on the Jussieu campus in central Paris, the SAFIR platform develops and applies ion beam analytical methods around a 2.5 MV Van de Graaff accelerator. We have recently developed a new PIXE method using Kossel diffraction with an Xray camera [1,2]. The present project will build on this success, with the help of a team of engineers (vacuum/UHV, mechanical, electronic) and of the scientific team which has a long experience in Ion Beam Analysis.
Constraints and risks
Work with a particle accelerator that produces ionising radiation
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