Detection of fast neutrons with the Medipix-2 pixel detector
Nucl. Instr. and Meth. A, Volume: 591, Issue:1, Pages: 71-74, doi: 10.1016/j.nima.2008.03.027
Neutron radiography using thermal and fast neutrons is becoming increasingly important for scientific, technical, security and other applications. In the past, the Medipix-2 imaging detector was successfully adapted for thermal neutron imaging in our group by adding a 6LiF neutron converter. Recently, the Medipix-2 detector was modified for fast neutron imaging. The Medipix-2 device consists of a silicon pixel detector (256 x 256 square pixels, 55 um x 55 um each) which is bump-bonded to a readout chip. Fast neutrons are detected through proton recoil from a 1 mm thick polyethylene layer placed on the detector surface. Basic detection and imaging properties of the detector were calculated, simulated and measured. The measurements were done using an AmBe neutron source, as well as external neutron beams of the Sparrow reactor at the Czech Technical University in Prague and of the high-flux reactor at Institut Laue-Langevin (ILL) in Grenoble, respectively. The detector provided a reasonable signal to background ratio of about eight at the neutron beam of ILL’s Neutrograph neutron radiography and tomography station. The estimated spatial resolution was at a level of 100 um. A demonstrational image of a sample taken with fast neutrons will be presented as well.
Cite article as:
Z. Vykydal, "Detection of fast neutrons with the Medipix-2 pixel detector", Nucl. Instr. and Meth. A, Volume: 591, Issue:1, Pages: 71-74, doi: 10.1016/j.nima.2008.03.027 (2008)