Speaker
Description
In order to perform measurements of high-energy neutron fields, it is necessary to calibrate instruments in reference fields at energies from 20 MeV up to an energy approaching 1 GeV.
The calibration of instrumentation for high-energy neutrons can be achieved in iThemba Laboratory for Accelerator-Based Sciences (TLABS) where a relatively high yield of quasi-monoenergetic neutrons up to 200 MeV can be produced via the 7Li(p,n) reaction.
However, several technical limitations of the neutron beam facility impair accurate measurements so that upgrading the facility is needed. The most important improvement necessary at the present neutron beam facility in vault D is the reduction of the neutron background.
This work aims at estimating the neutron background in different location of the present experimental area of iThemba Labs (i.e. vaultD) by simulating neutron transport with MCNPX for neutrons generated by irradiation of a lithium target with incident proton beams of 66 MeV and 200 MeV. The identification of the main neutron leakage paths will also be investigated. These results combined with measurements (planned in January 2019) of the neutron background in vaultD will provide a first step to a full set of recommendations for the upgrade of the facility.
