Photoluminescence and radiation response properties of Ce³⁺-doped CsCaCl₃crystalline scintillator

Abstract

In this paper, we report on the photoluminescence and scintillation properties of a newly developed CsCaCl 3 :Ce (0.5 mol%) crystalline scintillator grown by the vertical Bridgman method. The fluorescence quantum efficiency for the Ce 3+ characteristic emission bands centered at around 350-400 nm was 76% under excitation at 330 nm light. The photoluminescence decay time of the Ce 3+ was approximately 32 ns. When x-ray excited the crystal, intense emission bands were observed at 350-400 nm, and could be attributed to the Ce 3+ emission. The scintillation light yield of the developed crystal was ∼7600 ph MeV −1 compared to a NaI:Tl commercial scintillator, and the principal scintillation decay time was approximately 340 ns plus two fast components of around 1.6 ns and 45 ns.

Inorganic scintillating materials and scintillation detectors

“…With the knowledge of a similar compound, Cs 2 ZrCl 6 , the emission origin was blamed for the charge-transfer luminescence of the [HfCl 6 ] 2− anion complex. Motivated by this work, we have further developed non-hygroscopic halide scintillators, including Tl- and In-doped CsCl, 119) TlCdCl 3 , 120) Tl- and Ce-doped Cs 2 HfCl 6 , 121) Rb 2 HfCl 6 , 122) Ce-doped CsCaCl 3 123) and TlMgCl 3 . 124) Among these newly developed scintillators, especially TlMgCl 3 shows the most promising properties of a high light yield (46,000 ph/MeV), a high energy resolution (5% at 662 keV) and a relatively fast decay (60 ns).…”

Characterizations of CsSrCl3:Ce Crystalline Scintillator

“…From the calculation, the decay time was found to be approximately 28 ns, which is close to the value for CsCaCl 3 :Ce (τ = ~32 ns) reported in a previous study. (22) Figure 4 illustrates the scintillation spectrum of CsSrCl 3 :Ce (0.5 mol%). The spectrum shows intense emission bands peaking at 360 and 385 nm, and can be assigned to the transitions from the 5d 1 excited state to the 4f ( 2 F 5/2 , 2 F 7/2 ) ground states owing to the Ce…”

“…In addition, a weak emission band peaking at 300 nm was observed, which appears to be similar to that of CsCaCl 3 :Ce reported previously. (22) Macdonald et al studied the intrinsic luminescence properties including radiative core-valence luminescence (CVL) in an undoped CsSrCl 3 crystal. They observed the intrinsic emission peaking at 250-400 nm under excitation by X-rays.…”

“…The result is similar to the decay components for Cs 2 LiYCl 6 :Ce, Cs 2 LiYBr 6 :Ce, and CsCaCl 3 :Ce. (22,30) Further experimental investigations are required for the confirmation of the proposed scintillation mechanisms behind the decay time. Figure 6 illustrates the 137 Cs-gamma-ray-induced pulse height spectra for CsSrCl 3 :Ce (0.5 mol%) and the NaI:Tl commercial scintillator.…”

“…Auger-free luminescence (AFL), that is, radiative electric transition from the valence band to the outermost core band, in undoped CsMgCl 3 , CsCaCl 3 , and CsSrCl 3 crystals have been intensely studied because of their interesting characteristics such as fast decay times with high thermal stability. (6)(7)(8)(9) The rare-earth-, transition-metal-, and s 2 -ion-doped perovskite chloride crystals have attracted the most attention as the phosphor, (10)(11)(12)(13)(14)(15) magnetic material, (16)(17)(18)(19) and scintillator, (19)(20)(21)(22)(23) and then their crystal growth and characterizations have been reported by some researchers. Among the rare-earth-doped crystals, CsCaCl 3 :Eu and CsSrCl 3 :Eu are proposed to be promising X-ray and gamma-ray scintillators because of their high light yield (~18000 photons/MeV) owing to a 5d-4f allowed transition of Eu…”