Development of a large-area monolithic 4×4 MPPC array for a future PET scanner employing pixelized Ce:LYSO and Pr:LuAG crystals

33000 photons per MeV from mixed (Lu_075Y_025)_3Al_5O_12:Pr scintillator crystals

“…Since the overall scintillation properties of LuAG:Pr were clearly better than those of its isostructural counterpart Y 3 3 Al 5 O 12 :0.2%Pr crystals with 0.9 ≤ x < 1 and observed light outputs between 15000 and 16500 ph/MeV. More promising results were reported by Kamada et al [7] for μPD-grown Lu 2 YAl 5 O 12 :1%Pr samples, displaying yields up to 24500 ph/MeV.…”

“…1. The values of scintillation yield and energy resolution of all the studied crystals, derived from their spectra, are summarized in Table 2 On the way to explain our motivation to grow and investigate the (Lu x Y 1-x ) 3 Al 5 O 12 :Pr crystals and to get across the reported enhancement of yield in LuYAG:Pr compared to LuAG:Pr we remind that the precedent studies on the light output of LuAG:Pr used to indicate some room for improvement. In particular, it was noticed that at 450 K the yield of LuAG:Pr was higher by about 40% than at RT [9].…”

“…The crystals of (Lu x Y 1-x ) 3 Al 5 O 12 :Pr (x = 0.25, 0.50, 0.75) were grown at ITME, Warsaw, by the Czochralski method using the Cyberstar Oxypuller 05-03 equipment with an inductive Hüttinger generator. The thermal system consisted of a ∅50 × 50 mm 3 iridium crucible embedded in a Zircar zirconia grog, a ∅60 × 80 mm 3 passive iridium afterheater placed around the crucible top on the grog, and alumina heat shields around the afterheater.…”

“…The thermal system consisted of a ∅50 × 50 mm 3 iridium crucible embedded in a Zircar zirconia grog, a ∅60 × 80 mm 3 passive iridium afterheater placed around the crucible top on the grog, and alumina heat shields around the afterheater. The growth processes were performed in pure nitrogen atmospheres with a pulling rate of 1.0-1.5 mm/h, a rotation rate of 15-20 rpm, and a post-growth cooling time of at least 24 h. In this way optically high-quality single crystals with diameters up to 1 inch and about 2 inch long were obtained.…”

“…With a density of 6.7 g/cm 3 , an exquisite energy resolution of 4.6% (at 662 keV), and a fast decay constant of 20 ns, it quickly attracted a lot of attention and was considered and/or implemented into diverse applications, mostly in the field of medical diagnostics [2,3]. Among a few weaker points of LuAG:Pr there was its scintillation light yield which, not exceeding 20000 ph/MeV, rather failed to measure up to present-day standards and expectations.…”