title: A new neutron monitor and extended conversion coefficients for HP(10).
abstract: A new personal dose equivalent monitor for neutrons, the 'HpSLAB', is introduced. The device consists of a 30x30x15 cm3 polymethyl-methacrylate slab hosting a superheated drop detector embedded at a depth of 10 mm. The personal dose equivalent monitor was characterised experimentally with fast neutron calibrations in the 0.144-14.8 MeV range and numerically with Monte Carlo simulations. In order to evaluate the performance of the device, its response was compared to the fluence-to-directional dose equivalent conversion coefficients, hp(10;alpha,E). Since published coefficients only cover neutron angles of incidence up to 75 degrees, a new extended set of coefficients was computed for angles of incidence up to 180 degrees. The method used in these calculations was the very same used in the generation of the dose equivalent coefficients recommended by International Commission on Radiological Protection publication 74. The response of the HpSLAB follows with good approximation the trend of the conversion coefficients for monoenergetic neutrons above approximately 0.5 MeV. The device was extensively tested in broad-spectrum workplace-fields encountered at nuclear installations and its response was on average within a factor 1.4 of the reference personal dose equivalent values, regardless of angle and energy distribution of the neutron fluence.
authors.affiliation: Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, I-56126 Pisa, Italy. francesco.derrico@ing.unipi.it
authors.forename: F
authors.initials: F
authors.lastname: d'Errico
authors.forename: V
authors.initials: V
authors.lastname: Giusti
authors.forename: B R L
authors.initials: BR
authors.lastname: Siebert
mesh_terms: D000465:Algorithms; D004781:Environmental Exposure / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D038622:Internationality; D009502:Neutrons; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000295:instrumentation*; D011835:Radiation Protection / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity