K Tsutsumi

Publications (7)7.24 Total impact

• Article: Scintillation Properties of Praseodymium Doped LuAG Scintillator Compared to Cerium Doped LuAG, LSO and

  L. Swiderski, M. Moszynski, A. Nassalski, A. Syntfeld-Kazuch, T. Szczesniak, K. Kamada, K. Tsutsumi, Y. Usuki, T. Yanagida, A. Yoshikawa, W. Chewpraditkul, M. Pomorski
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  ABSTRACT: Properties of praseodymium and cerium doped Lutetium Aluminum Garnet (LuAG) were compared with cerium doped Lutetium Oxyorthosilicate (LSO) and Lanthanum Bromide (LaBr₃). Light yield, its non-proportionality relative to 662 keV gamma -rays and the dependence of the energy resolution on energy of the detected gamma -rays were measured. LuAG:Pr turned out to have good proportionality, with deviation from unity around 10% at 16.6 keV and 3% at 59.5 keV. This, together with relatively high light yield of 5600 phe/MeV results in a very good energy resolution of LuAG:Pr of 5.1% measured with 662 keV gamma-rays. The measured time resolution of 308 ps is significantly larger than that of 166 ps obtained for LSO:Ce. This can be explained by smaller light yield of LuAG:Pr and the fact that only about 25% of its scintillation is emitted in short decay time modes of 17.6 ns and 52 ns, while the rest is decaying with long time modes of 1.4 mus and 9 mus.
  IEEE Transactions on Nuclear Science 09/2009; · 1.45 Impact Factor
• Article: Light Yield Non-Proportionality and Energy Resolution of Praseodymium Doped LuAG Scintillator

  L. Swiderski, M. Moszynski, A. Nassalski, A. Syntfeld-Kazuch, T. Szczesniak, K. Kamada, K. Tsutsumi, Y. Usuki, T. Yanagida, A. Yoshikawa
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  ABSTRACT: Scintillation properties of praseodymium doped LuAG have been investigated. The crystal is a dense (6.7 g/cm³) scintillator with a short decay time around 20 ns and wavelength emission spectrum peaked at 310 nm. The tested sample was 10 mm times 10 mm times 5 mm cuboid, polished on all surfaces. The dopant concentration amounts to 0.23 mo1%. A light yield of 16000plusmn1600 ph/MeV was measured using high sensitivity (13.7 muA/1mF) Photonis photomultiplier (PMT) XP5500B. High quantum efficiency of this PMT (35%) allowed us to register 5600plusmn400 phe/MeV using 12 mus shaping time in the spectroscopy amplifier. The measured energy resolution was equal to 5.0plusmn0.1%. Response of LuAG:Pr to gamma-rays was found to be proportional over wide energy range. Deviation from proportionality does not exceed 10% at 16.6 keV. This results in good intrinsic energy resolution of LuAG:Pr amounting to 3.0plusmn0.3%, measured with 662 keV gamma-rays from ¹³⁷Cs.
  IEEE Transactions on Nuclear Science 07/2009; · 1.45 Impact Factor
• Article: Scintillation Properties of 2-Inch-Diameter (LuAG) Single Crystal

  K. Kamada, T. Yanagida, K. Tsutsumi, Y. Usuki, M. Sato, H. Ogino, A. Novoselov, A. Yoshikawa, M. Kobayashi, S. Sugimoto, F. Saito
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  ABSTRACT: Pr:LuAG crystals possess interesting properties, such as high density, high light yield, and very fast 5d-4f emission decay time. Recently, we developed a Pr:LuAG single crystal with a diameter of 2 inches for scintillator applications, such as medical imaging. In this study, Pr-doped Lu₃Al₅O₁₂ (Pr:LuAG) single crystals with a diameter of 2 inches were grown by means of the Czochralski method; a body length of up to 90 mm was achieved. The Pr:LuAG crystals produced a homogeneous light yield with approximately 2.5 times less intensity compared to that produced by a conventional Ce:LSO crystal. A sample with dimensions of 5 mm times 5 mm times 1 mm exhibited energy resolutions of 4.8% at 662 keV, as measured by using a photomultiplier (PMT: Hamamatsu H6531), and 5.8% at 662 keV, as measured by using an Avalanche photodiode (APD: Hamamatsu S8664-55). The Pr:LuAG crystals exhibited a very fast rise time of approximately 0.4 ns, excited by a pulsed X-ray at room temperature. The decay time was approximately 18 ns, along with a noticeable presence of slower decay components (with a decay time of 55.0 ns). Furthermore, the Pr:LuAG crystals showed good linearity between the energy and pulse height within approximately 4% of the standard deviation in the range from 122 keV (¹⁵²Eu) to 1.4 MeV (²⁴¹Am) .
  IEEE Transactions on Nuclear Science 07/2009; · 1.45 Impact Factor
• Source

  Available from: Alan Owens

  Article: Scintillation Properties of Praseodymium Activated Single Crystals

  W. Drozdowski, P. Dorenbos, J.T.M. de Haas, R. Drozdowska, A. Owens, K. Kamada, K. Tsutsumi, Y. Usuki, T. Yanagida, A. Yoshikawa
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  ABSTRACT: Scintillation properties of LuAG:Pr grown by Furukawa Co. Ltd., Japan, have been studied. The best crystals display light outputs up to 19000 ph/MeV and an energy resolution of 4.6% at 662 keV. The scintillation yield is found to be a function of size and temperature of the sample; it can be enhanced by 40% upon heating to 450 K. Radioluminescence spectra show both d - f and f - f transitions of Pr³⁺ ions; the contribution of the latter increases with temperature. The scintillation decays are complex, with a fast decay constant of 20 ns. The presence of ¹⁷⁶Lu induces high background activity.
  IEEE Transactions on Nuclear Science 09/2008; · 1.45 Impact Factor
• Article: Crystal Growth and Scintillation Properties of 2-Inch-Diameter (Pr:LuAG) Single Crystal

  K. Kamada, K. Tsutsumi, Y. Usuki, H. Ogino, T. Yanagida, A. Yoshikawa
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  ABSTRACT: In this work we tried to grow 2-inch-diameter and high quality Pr:LuAG single crystals by the Czochralski (Cz) method. To grow the large diameter Pr:LuAG single crystal, we have optimized growth conditions and the furnace design. As a result, we have succeeded in the growth of 2-inch-diameter Pr:LuAG single crystal with a length of 110 mm. To determine light yield and energy resolution the energy spectra were collected under 662 keV gamma-ray excitation (¹³⁷Cs source) and detection by a photomultiplier (Hamamatsu H7826). The light yield was around three times higher than that of BGO and almost homogeneous with increasing solidification fraction up to 0.32. The energy resolution was around 8%. Furthermore, scintillation decay time was around 23 ns and almost homogeneous all over the crystal.
  IEEE Transactions on Nuclear Science 07/2008; · 1.45 Impact Factor
• Conference Proceeding: Scintillation properties of 2-inch-diameter Pr: Lu 3 A1 5 O 12 single crystal

  K. Kamada, K Tsutsumi, Y Usuki, T Yanagida, M Sato, H Ogino, A. Novoselov, A Yoshikawa, M Kobayashi, S Sugimoto, F. Saito
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  ABSTRACT: Pr:LuAG has interesting properties of high density, high light yield and a very fast 5d-4f emission decay time. Recently we have develop 2-inch-diameter Pr:LuAG single crystal for scintillator applications such medical imaging and high-energy physics. In this report, we study uniformity of the light yield, energy resolution, decay time and gamma-ray response in the range from 59.5 keV (²⁴¹Am) to 1.4 MeV (²⁴¹Am).
  Nuclear Science Symposium Conference Record, 2007. NSS '07. IEEE;
• Conference Proceeding: Basic experiments on radiation imaging by using Pr:Lu3Al5O12 (LuAG) small crystalline pixels with various reflector

  K. Kamada, K. Tsutsumi, C. Suzuki, Y. Usuki, T. Yanagida, A. Yoshikawa, S. Yamamoto, F. Saito
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  ABSTRACT: Pr:LuAG have good scintillation properties of high energy resolution, very fast 5d-4f emission decay time, higher density and high light yield. In order to apply Pr:LuAG to medical imaging application such PET and PEM, the optimization of light output and energy resolution of scintillators is very important. Especially Therefore, to choose a suited reflector is very important because Pr:LuAG has short emission wave length at 310 nm. In this work, we studied spatial and energy resolution of pixilated Pr:LuAG with various reflectors (Teflon tape, ESR, BaSO4) by irradiation of ²²Na source. Using the BaSO₄ reflector, the light output has increased by ~210% compared to the ESR reflector, and ~170% compared to the Teflon tape reflector. The BaSO₄ reflector also resulted in the best improvement of the energy resolution up to 12%.
  Nuclear Science Symposium Conference Record, 2007. NSS '07. IEEE;