A neutron irradiation facility based on four 241Am–Be sources, each one with an activity of 111 GBq, placed in Plexiglas pipes inside a tank filled with water used both as a moderator and a biological shielding, has been realized at the Engineering Department of Palermo University. In view of its use as a testing tool in various research activities, a characterisation of the irradiator has been carried out through the determination of neutron and gamma-ray flux profiles, the evaluation of the thermal to total neutron flux percentage ratio and of the epithermal neutron shaping factor. To this aim, results of a Monte Carlo (MCNP5 code) simulation based on a previously validated source model have been compared with the experimental results obtained from TLD dosimeters and activated gold foils. Experimental values show a good agreement with MCNP5 evaluations, highlighting a gradually decreasing of dose values as a function of the distance from the lying plane of sources. Maximum values of experimental neutron fluxes have been found to be (3.73 ± 0.38) × 104 cm−2 s−1 (thermal) and (2.13 ± 0.25) × 104 cm−2 s−1 (epithermal and fast), with a percentage of 64% of thermal to total neutron flux and epithermal neutron shaping factor equal to −0.16 ± 0.04. Both neutron and gamma fluxes for the most used positions inside the irradiation channel can then be provided and the main parameters for any irradiation plane can be easily established.

Marchese N., Fiore D., Cottone D., Parlato A., Tomarchio E. (2020). Neutron and gamma-ray radiation fields characterisation in a 241Am–Be irradiator in view of its use as research testing tool. RADIATION PHYSICS AND CHEMISTRY, 170, 108705 [10.1016/j.radphyschem.2020.108705].

Neutron and gamma-ray radiation fields characterisation in a 241Am–Be irradiator in view of its use as research testing tool

Parlato A.;Tomarchio E.
2020-01-01

Abstract

A neutron irradiation facility based on four 241Am–Be sources, each one with an activity of 111 GBq, placed in Plexiglas pipes inside a tank filled with water used both as a moderator and a biological shielding, has been realized at the Engineering Department of Palermo University. In view of its use as a testing tool in various research activities, a characterisation of the irradiator has been carried out through the determination of neutron and gamma-ray flux profiles, the evaluation of the thermal to total neutron flux percentage ratio and of the epithermal neutron shaping factor. To this aim, results of a Monte Carlo (MCNP5 code) simulation based on a previously validated source model have been compared with the experimental results obtained from TLD dosimeters and activated gold foils. Experimental values show a good agreement with MCNP5 evaluations, highlighting a gradually decreasing of dose values as a function of the distance from the lying plane of sources. Maximum values of experimental neutron fluxes have been found to be (3.73 ± 0.38) × 104 cm−2 s−1 (thermal) and (2.13 ± 0.25) × 104 cm−2 s−1 (epithermal and fast), with a percentage of 64% of thermal to total neutron flux and epithermal neutron shaping factor equal to −0.16 ± 0.04. Both neutron and gamma fluxes for the most used positions inside the irradiation channel can then be provided and the main parameters for any irradiation plane can be easily established.
Settore ING-IND/20 - Misure E Strumentazione Nucleari
www.elsevier.com/locate/radphyschem
Marchese N., Fiore D., Cottone D., Parlato A., Tomarchio E. (2020). Neutron and gamma-ray radiation fields characterisation in a 241Am–Be irradiator in view of its use as research testing tool. RADIATION PHYSICS AND CHEMISTRY, 170, 108705 [10.1016/j.radphyschem.2020.108705].
File in questo prodotto:
File Dimensione Formato  
RPC 2020 - Proc ICDA-3.pdf

Solo gestori archvio

Tipologia: Versione Editoriale
Dimensione 2.17 MB
Formato Adobe PDF
2.17 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/400710
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 1
  • ???jsp.display-item.citation.isi??? 1
social impact