APPLICABILITY OF GSO SCINTILLATORS FOR WELL LOGGING

Cerium-doped gadolinium oxyorthosilicate (GSO:Ce) was developed as a scintillating material for application in positron emission tomography. We have studied the fundamental properties of this material, with particular attention to properties relevant to nuclear well logging applications and their temperature dependence. Initial evaluations indicated that this material had a number of properties which seemed to make it a favorable candidate for well logging applications, such as the reported decay time constant of 60 ns. Subsequent studies showed the presence of a longer, 600 ns, decay constant, which coupled with its extremely high thermal neutron absorption cross section and relatively low light output, raised questions about its suitability. We have studied the temperature dependence of GSO:Ce to better evaluate its applicability as a gamma-ray detector for nuclear well logging applications.