title: A telescope-design directional neutron spectrometer.
abstract: A directional spectrometer that uses a superheated emulsion of dichlorotetrafluoroethane at the centre of a 30 cm diameter moderating-sphere of nylon-6. The system has a telescope-design wherein the detector views a narrow solid angle of about 1/6 steradians. The hydrogenous sphere effectively attenuates laterally incident neutrons, thus providing a strong angular dependence of the response. The central detector is sequentially operated at seven temperatures between 25 and 55 degrees C in order to generate a matrix of nested response functions suitable for few-channel spectrometry. The response matrix of the system has been determined by calibrations with monoenergetic neutrons and by Monte Carlo neutron transport calculations. The double-differential unfolding method developed for this system applies the principle of maximum entropy and allows for the rigorous use of all a priori information. The spectrometer is intended for use in the mixed neutron/photon fields encountered in the nuclear power industry, being suitable for spatially distributed radiation sources with maximum neutron energies up to 10 MeV.
authors.affiliation: Department of Therapeutic Radiology, Yale University School of Medicine, 333 Cedar St, New Haven, CT 06510, USA. francesco.derrico@yale.edu
authors.forename: F
authors.initials: F
authors.lastname: d'Errico
authors.forename: V
authors.initials: V
authors.lastname: Giusti
authors.forename: M
authors.initials: M
authors.lastname: Reginatto
authors.forename: B
authors.initials: B
authors.lastname: Wiegel
mesh_terms: D016880:Anisotropy; D001822:Body Burden; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D018499:Linear Energy Transfer; D009502:Neutrons; D011829:Radiation Dosage; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D012062:Relative Biological Effectiveness; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000295:instrumentation* / Q000379:methods