New fast scintillators on the base of BaF2 crystals with increased light yield of 0.9 ns luminescence for TOF PET

Abstract Presently a growing interest to time-of-flight PET is observed in a number of experimental works using LSO as scintillation crystals. We propose to use as scintillators BaF 2 crystals and ceramics produced from identical material but with essentially more high light yield in the fast component of emission spectra. A light yield amplification of BaF 2 single crystal fast component of 2 to 2.5 times is achieved in crystals annealed in CF 4 and doped by scandium at concentration of 0.5 to 2.0 mol%. Ceramics from BaF 2 doped by Sc have amplification factor order of 1.7 to 2.5. One can consider to produce scintillator of size 10×10×20 mm 3 with an improved light transmission of ceramics in the range (200–250) nm up to single crystal level and with a light yield of 0.9 ns component at the level of 3000 to 4000 ph/MeV. Another promising scintillator obtained in our collaboration is BaF 2 :Tm 3+ . In this case one can have a scintillator in UV range with a time decay 0.9 ns and a strongly decreased yield of BaF 2 slow component.