Development of a novel macrostructured cathode for large-area neutron detectors based on the B-10-containing solid converter
2013 (English)In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, Vol. 727, 109-125 p.Article in journal (Refereed) Published
We present a novel design for a macrostructured cathode that can be coated with a thin layer of the B-10 solid converter and mounted to replace the Boron-lined flat parallel plates of a proportional counter used for slow neutron detection. The proposed design consists of a 3D regular pattern exhibiting millimeter deep grooves with an opening angle of alpha = 45 degrees, which could be created in the substrate material by milling or forming. When a commonly used coating method like magnetron sputtering is employed to deposit the Boron-layer, due to the line-of-sight distribution of the ions, the thickness of the coating on the side of the grooves will be reduced by a factor similar to sin alpha/2 with respect to the thickness of the layer deposited on a flat surface normal to the ion flux. The effective neutron absorption film thickness is in this case similar for the sidewalls of the grooves and a surface at normal incidence, yielding comparable absorption efficiencies. However, the escape efficiency for the reaction products is higher for the sidewalls, owing to the thinner coating. This leads to a higher overall detection efficiency for the grooved cathode when compared to a flat cathode with the same surface area and coated with a Boron layer with roughly the same thickness. In this paper we present and discuss the GEANT4 simulations performed to optimize the geometry of the cathode, the manufacturing and coating by magnetron sputtering, as well as the proof-of-principle measurements carried out in order to assess the performance of the proposed design.
Place, publisher, year, edition, pages
Elsevier , 2013. Vol. 727, 109-125 p.
Neutron detector, Boron converter, GEANT4, GARFIELD
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-97649DOI: 10.1016/j.nima.2013.06.003ISI: 000323557700017OAI: oai:DiVA.org:liu-97649DiVA: diva2:650007
Funding Agencies|German Federal Ministry of Education and Research (BMBF)|05E10WO1|2013-09-192013-09-192016-08-31