(Lu-Y)AlO$_{3}$:Ce Scintillator for Well Logging

Lutetium Yttrium Perovskite - (Lu
_x
- Y
_1-x
)AlO
₃
: Ce, LuYAP:Ce - is a cerium doped scintillation crystal that offers high light yield and high density. LuYAP:Ce with 70% lutetium content in (Lu-Y) system has been applied for medical imaging. Recently volume crystals with good transparency in the spectral range of scintillation have been obtained. It made possible detailed test of the material for well logging application. A unique combination of the parameters: high stopping power, fast and bright scintillation, light yield increase at high temperature makes them attractive for gamma-ray detection in a wide range of temperatures. Evaluation performance test of (Lu
_0.7
-Y
_0.3
)AIO
₃
: Ce scintillation crystal detector and widely used Nal(Tl), BGO and GSO crystal based detectors of the same size thetas 18 times 60 mm
³
has been performed. All crystals were assembled in aluminium case with light reflective material and attached to a high temperature PMTs. It was found that (Lu
_0.7
-Y
_0.3
)AlO
₃
:Ce based detector exhibits the most impressive set of operational characteristics: highest detection efficiency in integral and spectrometric gamma- and n-gamma well logging, excellent stability of the detector response with clear tendency to increase with temperature raise, stable signal-to-noise ratio in the temperature range 25 degC - 175 degC and high resistance to neutron activation. Shock and vibration tests also showed good mechanical stability of the material. Details of the tests and forthcoming application of the scintillator in well-logging are discussed.