(Gd,Lu)3(Ga,Al)5O12:Ce (GLuGAG) is a gamma-ray scintillator from the garnet family. It has high light yield and density, good energy resolution, fast response, and good coincident timing resolution. These properties make it a very promising scintillator for high energy radiography and Position Emission Tomography (PET) applications.
High-energy radiography (in MeV range) requires high stopping power defined by high density and effective Z. GLuGAG offers a good combination of stopping power and light yield making it an excellent alternative for CsI(Tl), CdWO4 and PbWO4. Its low afterglow allows for high repetition rates.
Fast counting and positron emission tomography (PET) are additional applications. High light yield combined with fast decay time can produce sub-nanosecond timing resolution, currently benchmarked at approximately 500 ps (FWHM) using a PMT (improved results are expected utilizing red-sensitive SiPMs.) It can also be used for neutron detection, as it has a high cross-section for thermal neutron absorption (48,890 barns). Thermal neutron capture generates a peak in the pulse height spectrum at ~70 keV. Thin layers of GLuGAG can be also be used for thermal neutron imaging.
GLuGAG is a stable and non-hygroscopic material. Its cubic crystal structure enables fabrication of large, uniform Transparent Optical Ceramic specimens. The properties of ceramic GLuGAG:Ce are nearly identical to single crystal GLuGAG, which is more difficult to grow in large sizes and requires longer, higher temperature processes to produce. RMD’s configurations include 1”x 1” right cylinders, 2.5” disks, 2”x 2”x 1.5” cuboid samples and arrays of different sizes for various applications.
GLuGAG Pixel Bars for Nuclear Imaging
Material: (Gd,Lu)3(Ga,Al)5O12:Ce (GLuGAG)
Melting Point: 1930°C
Density: 6.8 g/cm3
Crystal Structure: Cubic Water
Emission Spectral Range: 450-750 nm
Peak Scintillation Wavelength: 545nm
Decay Constants (Ce3+): 75 ns, 190 ns, 1300 ns
Scintillation Light Yield: 50,000 ph/MeV GEE for Thermal
Neutrons: 71 KeV X-ray
Absorption Coef. at 100 KeV: 12.6 cm-1 X-ray
Absorption Coef. at 662 KeV: 0.07 cm-1
Radiation Length: 1.26 cm
Refractive Index: 1.81±0.02 @480 nm