Gamma Ray Spectra and Shielding Survey of the University of Maryland Reactor

Abstract

The gamma ray spectra of the University of Maryland reactor were measured at the beam tube which extends from the side of the reactor to the core, the thermal column and the top of the reactor. There were three gamma ray spectra measurements at the beam tube : gamma ray spectra recorded by a single-channel spectrometer when the reactor was shut down and when the reactor was operated at different power levels and the gamma ray spectra recorded by a 256-channel spectrometer when the reactor was at different levels of power. However, only the single channel spectrometer was used to measure gamma ray spectra at the thermal column and the top of the reactor; some gamma ray spectra were recorded at the thermal column when the reactor was operated at various power levels and a gamma ray spectrum was recorded at the top of the reactor when the reactor was operated at full licensed power of 10 kw. The gamma ray shielding survey of the reactor was done by a Geiger-Muller survey meter when the reactor was running at full power of 10 kw. The highest level found was about 0.8 millirem per hour which was at the side of the reactor at core level. A calculated gamma ray level was near this value.