Development of a spatially resolving, high-magnetic-field compatible detector for ultracold neutrons

• Applicant: Professor Dr. Tobias Reich, since 3/2023
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 447846734

In this project, a spatially resolving, high-magnetic-field compatible detector for ultracold neutrons (UCN) will be developed.Silicon Photomultipliers will be used to detect light generated in ZnS(Ag) scintillator foils, which will be coated with a thin layer of 10B.While UCN detectors based on 10-boron coatings already exist, no large area, pixelated and magnetic field compatible detector exists yet. However such a detector will be highly versatile and useful for e.g. neutron EDM and neutron lifetime measurements, as in such experiments high magnetic fields are present for UCN spin analysis or UCN confinement, and spatial resolution is necessary in order to push systematic effects to the lowest possible levels.In the framework of a PhD thesis the project will be tackled in 3 phases, a 1-pixel prototype, afterwards a 25 pixel prototype and finally a detector with an area of about 100 x 100 mm2 and 100 pixels, a spatial resolution of 10 mm, will be developed.For the first two phases, pre-experiments with alpha sources instead of boron and neutrons will be performed, to establish light collection efficiency and light range.The Detectors will be repeatedly tested with ultracold neutrons (UCN) at the UCN source at the TRIGA Mainz research reactor at Johannes Gutenberg University Mainz and their efficiency will be compared to existing detectors.The final detector will also be compared to 3He based detectors in a beamtime at Paul Scherrer Institute, Switzerland, which are being developed there.The detectors of phase 2 and 3 need high performance readout electronics. Initially, external commercially available readout electronics will be used for development and testing, later dedicated in-situ readout electronics based on ASIC technology and FPGAs will be be developed and tested.

• DFG Programme: Research Grants
• International Connection: Switzerland
• Cooperation Partner: Dr. Bernhard Lauss
• Ehemaliger Antragsteller: Professor Dr. Dieter Ries, until 3/2023