The Scintillation Counter
The scintination counter is a relatively new instrument for the detection and measurement of nuclear and atomic radiations. Light produced in a fluorescent material by the incident particle or quantum Is picked up by a photomultiplier tube. The resultant photoelectric emission is amplified in the photomultiplier by a series of secondary-emission stages. This paper is a review of the present state of knowledge regarding the characterstics of the counter and the details of Its operation.
SCINTILLATION COUNTERS FOR SLOW NEUTRONS
The suitability of boric oxide glass containing phosphorescent materials for use as scintillation counters for slow neutrons is investigated both theoretically and experimentally. A theory is developed which can be used for predicting counting efficiencies of the phosphor disks given optical data and neutron absorption properties of the materials present, and physical details of the experimental arrangement. This is compared to experiment in one case with good agreement. It is shown that there are serious practical difficulties in the use of a boric glass phosphor as a slow neutron detector.
Cathodo-luminescence: part I. Growth and decay processes
The active centre theory of luminescence, with certain assumptions, leads to the expectation of exponential growth and decay processes in light emission. Measurement has shown the widespread occurrence of exponential processes, though the details are much more complex than the simple theory would suggest. The effects of changing current density and temperature were examined. The phosphors studied fell into two classes, distinguished mainly by the rates of the processes measured. Some non-exponential processes were found, especially in long time decay, but none were definitely bimolecular.