The application of a new geometry correction function for the calibration of neutron spherical measuring devices using large volume neutron sources

A new geometry correction function for the calibration of spherical dose equivalent survey meters, using large volume neutron sources, has been developed and is presented. This is a modification of the geometry factor formalism developed by Hunt for the correction of non-parallelism of the field which is usually produced by a small neutron source near a spherical detector. This function is used to obtain a functional distance parameter specifying the source virtual centre and the geometry correction factor. The consistency of this correction factor and the source virtual centre, derived in this study, have been investigated by analysing the data of close and far distances using two calibration models applicable in these ranges of distances. (author)