Thermal and epithermal neutron flux distributions measurement in thermal column of TRR using an experimental-simulation method.
For designing an appropriate neutron beam, the determination of neutron flux at any irradiation facility is an important key factor. Due to the importance of determining the thermal and epithermal neutron fluxes in a typical thermal column of a reactor, a simple and accurate technique is introduced in this study. Absolute thermal and epithermal fluxes were measured experimentally at a certain point using the foil activation method by neutron bombardment of bare and cadmium covered Au foils. The relative neutron fluxes were also derived simply by means of Monte Carlo simulation by accurate modelling of the reactor components. Finally, by normalization of the relative distribution flux with regard to information about the absolute neutron flux, the accurate thermal and epithermal neutron distributions were derived, separately.
Thermal neutron imaging through XRQA2 GAFCHROMIC films coupled with a cadmium radiator
Abstract A simple and inexpensive method to perform passive thermal neutron imaging on large areas was developed on the basis of XRQA2 GAFCHROMIC films, commonly employed for quality assurance in radiology. To enhance their thermal neutron response, the sensitive face of film was coupled with a 1 mm thick cadmium radiator, forming a sandwich. By exchanging the order of Cd filter and sensitive film with respect to the incident neutron beam direction, two different configurations (beam-Cd-film and beam-film-Cd) were identified. These configurations were tested at thermal neutrons fluence values in the range 109–1010 cm−2, using the ex-core radial thermal neutron column of the ENEA Casaccia – TRIGA reactor. The results are presented in this work.
The three dimensional map of dose components in a head phantom for boron neutron capture therapy
The in-phantom measurement of physical dose distribution and construction of 
 a convenient phantom is very important for boron neutron capture therapy 
 planning validation. In this study we have simulated a head phantom, 
 suggested for construction in boron neutron capture therapy facilities, and 
 calculated all relevant dose components inside of it using the Monte Carlo 
 code MCNPX. A “generic” epithermal neutron beam with a broad neutron 
 spectrum, similar to beams used for neutron capture therapy clinical trials, 
 was used. The calculated distributions of all relevant dose components in 
 brain tissue equivalent were compared with those in water. The results show 
 that water is a suitable dosimetry material and that the simulated head 
 phantom is a suitable design for producing accurate three-dimensional maps 
 of dose components at enough points inside of the phantom for boron neutron 
 capture therapy dosimetry measurements and the use of these dose maps in beam 
 development and benchmarking of computer-based treatment codes.