The use of a calorimeter for neutron dosimetry.
The dose given to a polythene energy absorber in the radiation field from a 14 MeV neutron generator has been measured calorimetrically. The calorimeter was calibrated by giving the energy absorber a known dose of gamma-rays. The dose measured in this way was compared with that determined with a polythene-ethylene ionization chamber, and the two results agreed to better than 1%, though the estimated uncertainties on the calorimeter and ionization chamber results were each about 4%. This result can be used to determine a value of the ratio Wn/We, for 14 MeV neutrons in ethylene, where Wn is the W value for the charged particles generated in the neutron field in ethylene, and We is the W value for electrons in the same gas. The measured value of Wn/We was found to be 1.07 plus or minus 3.9%. The significance of the 'thermal defect' in polythene is discussed.
D002151:Calorimetry; D003037:Cobalt Radioisotopes; D005030:Ethylenes / Q000528:radiation effects; D005214:Fast Neutrons; D009502:Neutrons; D009686:Nuclear Physics; D009688:Nuclear Reactors; D011829:Radiation Dosage; D013696:Temperature
D003037:Cobalt Radioisotopes; D005030:Ethylenes