Prospects for dense, infrared emitting scintillators

We present results from an ongoing search for inorganic scintillators for X-ray and gamma-ray detection. We measure the scintillation properties (luminous efficiency, decay time, and emission wavelength) of powdered samples excited by brief X-ray pulses. To find scintillators that are compatible with silicon photodetectors, we have tested over 1,100 samples using a photomultiplier tube with a GaAs:Cs photocathode, which is sensitive to 200-950 nm emissions. Optical filters are used to block emissions that are observable with bialkali PMTs. Several lanthanide and transition metal ions, molecular complexes, and II-VI compounds are known to have strong emissions at wavelengths >500 nm. We find that several compounds exhibit emission intensities comparable to commercial phosphors in the 600-900 nm range, including Eu and Sm doped LuPO/sub 4/, ScPO/sub 4/, and YPO/sub 4/. Significant emissions are also observed from Tb, Dy, Er, Pr, and Tm doped phosphates, as well as several intrinsic compounds, notably Hg/sub 2/Cl/sub 2/. Scintillation characteristics of promising compounds (in powdered or small crystal form) are presented.

[1]  K. Petermann,et al.  UV-spectroscopy and band structure of Ti:YAlO3 , 1997 .

[2]  A. Gruzintsev Investigation of complex anisotropic centers of blue and green luminescence of SrS:Ce by the method of the polarized intracentral photoexcitation , 1997 .

[3]  H. Schulz,et al.  Infra-red luminescence of mercurous chloride crystals , 1996 .

[4]  T. Iguchi,et al.  The use of 1.5 /spl mu/m infrared light from a cooled scintillator for optical fiber based system , 1995, 1995 IEEE Nuclear Science Symposium and Medical Imaging Conference Record.

[5]  W. Moses,et al.  Scintillator characterization using the LBL pulsed X-ray facility , 1995 .

[6]  W. W. Moses,et al.  Internet access to data for scintillation compounds , 1995 .

[7]  W. Moses,et al.  A room temperature LSO/PIN photodiode PET detector module that measures depth of interaction , 1995 .

[8]  W. Moses,et al.  LuAlO/sub 3/:Ce-a high density, high speed scintillator for gamma detection , 1995 .

[9]  W. Moses,et al.  Characterization Of A Pulsed X-ray Source For Fluorescent Lifetime Measurements , 1993, 1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference.

[10]  W. Moses,et al.  Design of a pulsed X-ray system for fluorescent lifetime measurements with a timing accuracy of 109 PS , 1992, IEEE Conference on Nuclear Science Symposium and Medical Imaging.

[11]  P. Dorenbos,et al.  Detection of CdS(Te) and ZnSe(Te) scintillation light with silicon photodiodes , 1992 .

[12]  W. Moses,et al.  X-ray fluorescence measurements of 412 inorganic compounds , 1991, Conference Record of the 1991 IEEE Nuclear Science Symposium and Medical Imaging Conference.

[13]  W. Moses,et al.  Prospects for new inorganic scintillators , 1990 .

[14]  W. Moses,et al.  Cerium fluoride, a new fast, heavy scintillator , 1989 .

[15]  G. Mageras,et al.  A measurement of the light yield of common inorganic scintillators , 1988 .

[16]  T. Hoshina,et al.  Red luminescence of Ce3+ due to the large stokes shifts in Y2O2S and Lu2O2S , 1981 .

[17]  W. H. Turner Photoluminescence of color filter glasses. , 1973, Applied optics.

[18]  W. Lehmann,et al.  Fast Cathodoluminescent Calcium Sulfide Phosphors , 1972 .

[19]  G. E. Thomas,et al.  Measurement of the Time Dependence of Scintillation Intensity by a Delayed‐Coincidence Method , 1961 .

[20]  A. Kaminskiĭ,et al.  Crystalline Lasers: Physical Processes and Operating Schemes , 1996 .