Rikito Murakami

Growth and scintillation properties of Ce doped Gd2Si2O7/SiO2 eutectics

Ce:Gd2Si2O7/SiO2 eutectic was grown by the μ-PD method. The square-shape sample with a side of 5 mm and a length of 15 mm was obtained. Two phases of orthorhombic Gd2Si2O7 and SiO2 was observed. Rod-phase was SiO2 and matrix phase was Gd2Si2O7. Ce3+ 4f5d emission have been observed at 400nm. The sample showed light yield of around 16,000 photons/MeV. Scintillation decay time was 46.3ns(21%) 249ns(79%).

Luminescence properties of Pr-doped (La,Gd)2Si2O7 grown by the floating zone method

Scintillation properties of a Pr-doped gadolinium lanthanum pyrosilicate (Pr:La-GPS) crystal grown by the floating zone (FZ) method were investigated, because the Pr3+ 5d–4f transition is expected to show a shorter decay time than the Ce3+ 5d–4f transition. In both α-ray radioluminescence and photoluminescence spectra, the emission peak related to the Pr3+ 5d–4f transition was observed at around 350 nm. The photoluminescence decay time of Pr:La-GPS was found to be as short as ~23 ns, whereas Ce:La-GPS had a decay time of ~31 ns.

Single Crystal Growth and Co-doping Effects of Lanthanum Substituted Gadolinium Pyrosilicate Scintillator

Ca 100, 200, 500, 1000 and 3000 at. ppm co-doped (Ce0.01,La0.3Gd0.69)2Si2O7 single crystals were grown by the μ-PD method. Luminescence and scintillation properties such as radioluminescence spectra, light yield and decay time were evaluated. Expected Ce3+ 4f5d emission have been observed in 350-430nm peaking at 360nm. Emission intensity took maximum at the Ca 100at.ppm co-doped sample and decreased by increasing the Ca concentration. The Ca 100at.ppm co-doped sample showed the highest light yield of around 20,000 photons/MeV. Scintillation decay time was accelerated with increasing Ca concentration. Scintillation decay time of the Ca 0, 100, 200, 1000 and 3000 at. ppm co-doped samples were 66.5ns(21%) 468ns(79%) and 44.0ns(22%) 430ns(78%), respectively.