Characterization and Calibration of Novel Semiconductor Detectors of Thermal Neutrons for ESA Space Applications

0385327 - ÚJF 2013 eng C - Conference Paper (international conference)
Kohout, Z. - Granja, C. - Králík, M. - Owens, A. - Venn, R. - Jankowski, L. - Pospíšil, S. - Sopko, B. - Vacík, Jiří
Characterization and Calibration of Novel Semiconductor Detectors of Thermal Neutrons for ESA Space Applications.
2011 IEEE Nuclear Science Symposium Conference Record. IEEE, 2011, s. 400-404. ISBN 978-1-4673-0118-3. ISSN 1082-3654.
[2011 IEEE Nuclear Science Symposium Conference. Valencia (ES), 23.10.2011-29.10.2011]
Grant - others:ESA C22908/09/NL/CBi
Institutional support: RVO:61389005
Keywords : semiconductor detectors * thermal neutrons * space applications
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

For the study and detection of neutrons in space environments such as planetary and earth orbiting missions semiconductor silicon diode detectors have been characterized and calibrated at various thermal neutron sources. Two types of diodes adapted for thermal neutron detection were investigated: silicon MESA planar detectors equipped with thin 6LiF layers and silicon heterodiodes with a layer of natural boron or enriched 10B. The response and absolute detection efficiency have been measured. The influence of bias voltage and converter layer thickness were studied. As neutron sources we used a homogenous isotropic thermal neutron field by a set of PuBe radionuclide sources placed in a graphite pile as well as a parallel thermal neutron beam with high Cd ratio (105) and suppressed gamma background. Depending on the converter layer thickness and/or boron layer thickness as well as the choice of the threshold level, efficiencies of approximately 1% are obtained for both the silicon diodes with thin 6LiF and the boron rich silicon detectors. These values guarantee optimal stability of operation in remote and different environments as well as maximum signal-to-noise ratio by enhanced suppression of unwanted signals and gamma background.
Permanent Link: http://hdl.handle.net/11104/0214613