Testing of small detectors with glass rod light guides for multiplicity measurement purposes

Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2012

In this paper we investigate the applicability of small scintillators with glass rod light guides to measure both neutrons and gamma rays from the sample. Experimental test of these detectors and their suitability for the task can be performed at Lund University using natural uranium rods, therefore the MCNPX simulation set-up corresponds to the Lund con- figuration. The long-term goal of this research is to develop a method of joint-multiplicity counting for fuel evaluation into a technology capable of quantifying plutonium in the fuel pool, where a lot of factors, such as presence of neutron absorbers (boron acid), can affect al- most all parameters, such as multiplication etc. Therefore, part of the present investigations was devoted to the development of a direct method for determination of the concentration of boron acid in the fuel pool using scintillation detectors with further correction of mea- surement results. For this purpose we suggest a method which utilizes a relation between gamma lines with energy of 480 keV and 2.23 MeV for the direct evaluation of concentration of boron acid in water. Test results of the new method, and an answer to questions regarding the ability to measure both neutron and gamma rays using small scintillation detectors with glass rod light guides are provided in this paper.