1997 年度実績報告書

高エネルギー粒子検出器用酸化物シンチレータ結晶の開発

研究課題

研究課題/領域番号	08555156
研究機関	湘南工科大学
研究代表者	石井満湘南工科大学, 工学部, 教授 (80212827)
研究分担者	薄善行古河機械金属(株), いわき工場, 主任研究員石橋浩之日立化成工業(株), 筑波開発研究所, 研究員原和彦筑波大学, 物理学系, 講師 (20218613) 小林正明高エネルギー加速器研究機構素粒子原子核研究所, 教授 (40013388)
キーワード	タングステン酸鉛 / 珪酸ガドリニウム / 引き上げ法 / シンチレータ特性 / 放射線損傷 / 蛍光減衰 / 光透過率
研究概要	1.PWO(PbWO_4)に関する研究 (1)PWO結晶のシンチレータ特性は、結晶中の不純物の低減とPb欠損に対する電荷補償によって改善されることを見い出した。すなはちPWOにPb^<2+>よりも原子価数が大きい不純物を添加すると、結晶の光透過率は向上し、蛍光の減衰および蛍光出力が改善される補ほか、放射線照射による劣化がなくなる。この事実からPWOはシンチレータとして実用化できると結論した。不純物の添加については、その他に発光機構やガンマ線照射後の熱ルミネッセンスの測定からその機構を検討した。 (2)結晶成長については、φ65mmx280mmLの大型結晶(La:80ppm)を育成し、実用的な20x20x230xmmLのシンチレータを採取・試作し、光学特性、シンチレータ特性、ガンマ線照射による劣化特性を測定評価した。この試作により、大型PWO結晶の育成、切断ならびに研磨加工技術も実証された。試作した大型シンチレータの傾向出力は7.2pe/MeVであり、10^7Radsのr線を照射すると6pe/MeVに減少したが、十分な信頼性があると結論できる。 2.GSO:Ce(Gd_2SiO_5:Ce)に関する研究 (1)大型結晶の育成については成長条件を検討し、φ80x300mmLの大型結晶が育成できる技術を確立した。 (2)上記の技術を応用して、Ceが0.5および1.5mo1%の二種のGSOを育成し、これから25x25x260mmの実用的寸法のシンチレータを採取して、評価した。長い結晶の蛍光出力の均一性は0.5mo1%Ceでは±4%、1.5mol%では17%であったが、エネルギ分解能はそれぞれ12%および15%であった。 (3)GSOにガンマ線を照射すると、蛍光出力が照射量とともに増加するPositive hysterisisがある。この現象は0.5mol%では10^5radsまでは15%増加し、照射量がさらに増すとますとますと減少する。これに対してCe1.5%ではhysteresis認められなかった。

研究成果

(34件)

すべてその他

すべて文献書誌 (34件)

[文献書誌] M.Ishii,et al.: "Mechanical Properties of PbWO_4 Scintillating Crystals." Nucl.Instr.Meth.A376. 203-207 (1997)
[文献書誌] M.Kobayashi,et al.: "Improvement in Transmittance and Decay Time of PbWO_4 Scintillating Crystals by La-doping." Nucl.Instr.Meth.A399. 261-268 (1997)
[文献書誌] S.Baccaro,et al.: "Influence of La^<3+> Doping on Radiation Hardness and Thermoluminescence Characteristics of PbWO_4" phys.stat.Sol.(a)16. R5-R6 (1997)
[文献書誌] M.Nikl et al.: "Decay Kinetics and Thermoluminescence of PbWO_4:La^<3+>" Appl.Phys.Letter.71(26). 3755-3757 (1997)
[文献書誌] M.Kobayashi,et al.: "Improvement of Radiation Hardness of PbWO_4 Scintillating Crystals by La-doping." Nucl.Instr.Meth.A404. 149-156 (1998)
[文献書誌] S.Baccaro,et al.: "Radiation Damage and Thermoluminescence of Gd-doped PbWO_4" Submitted to phys.Stat.Sol.,. (In press). (1997)
[文献書誌] M.Kobayashi,et al.: "Comparison of Radiation Damages of Different PbWO_4 Scintillating Crystals." Submitted to Nucl.Instr.Meth.,KEK Preprint. 97-144(In press). (1997.)
[文献書誌] V.V.Laguta,et al.: "Polaronic WO_4^<3-> Centers in PbWO_4 Single Crystals." J.Phys.Cond.Mat.,. (In press). (1998)
[文献書誌] K.Kurashige,et al.: "Mechanical Properties of a Gd_2SiO_5 Single Crystal." Japan,J.Appl.Phys.,. 36. 4122-2246. (1997)
[文献書誌] M.Tanaka,et al.: "Application of Cerium-doped Gadolinium Silicate Gd_2SiO_5:Ce Scintillator to Calorimeters in High Radiation Environment." Nucl.Instr.Meth.,. A404. 1998 (1998)
[文献書誌] H.Ishibashi,et al.: "Scintillation Performance of Large Ce-doped Gd_2SiO_5(GSO)Single Crystal." IEEE Nucl.Sci.Symp. & Medical Imag.Conf.Albuquerque,Nov.(In press). (1997)
[文献書誌] K.Kurashige,et al.: "Surface Polish of GSO Scintillator using Chemical Process," ibid.(In press). (1997)
[文献書誌] S.Yamamoto,et al.,: "A GSO Depth of Interaction Detector for PET." ibid.,. (In press). (1997)
[文献書誌] H.Murayama,et al.,: "A Depth Encoding in Multicrystal detector for PET." ibid.,. (In press). (1997)
[文献書誌] M.Kobayashi,et al.: "Large-size Bismuth Silicate(Bi_4Si_<13>O_<12>)Scintillating Crystals of Good Quality," Nucla.Instr.Meth.,. A400. 392-400 (1997)
[文献書誌] 寒川真樹ほか: "BSO-BGO固溶体シンチレータ結晶の可能性." Proc.of Workshop on Scintillating Crystals,High Energy Accelerator Res.Organ.(KEK),Tsukuba. 49-56. (1997)
[文献書誌] 廣瀬義朗ほか: "大型BSO(Bi_4Si_3O_<12>)単結晶の試作." Proc.of Workshop on Scintillating Crystals.57-64. (1997)
[文献書誌] H.Ishibashi,et al.,: "Large Ce-doped Gd_2SiO_5(GSO) Single Crystals 80 mm in Diameter." Pro.Workshop on Scintillating Crystals,ibid.69-71 (1997)
[文献書誌] H.Kurashige,et al.,: "Monte Carlo Simulation of Scintillator Efficiency for GSO Single Crystal." Pro.Workshop on Scintillating Crystals,ibid. 204-206 (1997)
[文献書誌] Y.Usuki,et al.,: "Proc.Workshop on Scintillating Crystals" Pro. Workshop on Scintillating Crystals,ibid. 207-216 (1997)
[文献書誌] M.Kobayashi,et al.,: "Recent Development in PbWO_4 Crystal Scintillators." Proc.Workshop on Scintillating Crystals,. 217-228 (1997)
[文献書誌] M.Ishii,et al.,: "Recent R&D on Oxide Scintillation Cryatals for Radiation Detectors." Proc.4^<th> Korea-Japan Electronic Materials Growth Symp.,Soul,. 131-134 (1997)
[文献書誌] M.Kobayashi.,et al.,: "Improvement in Scintillation Characteristics of PbWO_4 Scintillating Crystals by La-doping." SCINT'97,Proc.Inter.Conf.Inorganic Scintilators and Their Applications,Shanghai,P.R,China.Sept.22-25,1997.(In press). (1997)
[文献書誌] M.Tanaka,et al.,: "Stability of Ce doped Gd_2SiO_5(GSO) Scintillator under Irradiation." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] H.Ishibashi,et al.,: "Large Ce-Doped Gd_2SiO_5(GSO) Single Crystal 80 mm in diameter and its Performance." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] M.Nikl,et al.,: "Luminescence and Scintillation Decay Kinetics of PbWO_4 Single Crystals." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] S.Baccaro,et al.,: "Radiation Hardness Characteristics of PbWO_4 Single Crystals." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] M.Ishii,et al.,: "Growth and Characterization of Large BSO(Bi_4Si_3O_<12>) Crystals for Radiation Detectors." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] Fei Yiting,et al.,: "Phase Relation and Crystallization Behavior of Bi_2O_3-SiO_2 System." SCINT'97,ibid.,. (In press). (1997)
[文献書誌] Y.Usuki,et al.,: "Crystal Growth and Scintillation Characteristics of La doped PbWO_4 for High Energy Physics Experiments." Proc.Inter.Symp.Laser and Nonlinear Optical Materials,Singapore,Nov.3-5,1997,. 342-345 (1997)
[文献書誌] M.Kobayashi.,et al.,: "Scintillating Characteristics of Highly Concentrated Solid Soution Bal._xCexF_2+x with 0.1≦X≦0.45." SCINT'97,Proc.Inter.Conf.Inorganic Scintillators and Their Applications,Shanghai,P.R.China.Sept.22-25,1997.(In press). (1997)
[文献書誌] M.Kobayashi,et al.,: "Recent R&D Results on Heavy,Fast and Radiation-Hard Scintillating Crystals Based on Oxides." SSD-97,Yekaterinburg,Russia,Nov.28,1997.(In press). (1998)
[文献書誌] M.Kobayashi,et al.: "Scintillating Characteristics of Non-storichometric Phases Formed in MF_2-GdF_3-CeF_3 Systems with M=Ba,Sr and Ca." SSD-97,Yekaterinburg,Russia,Nov.28,1997.(In press). (1998)
[文献書誌] M.Kobayashi: "The PHOSPHORHANDBOOK (Ed.S.Shioya and W.M.Yen)" CRC Press,Inc., 541-550 (1998)

1997 年度 実績報告書

高エネルギー粒子検出器用酸化物シンチレータ結晶の開発

研究代表者

石井 満 湘南工科大学, 工学部, 教授 (80212827)

研究成果

[文献書誌] M.Ishii,et al.: "Mechanical Properties of PbWO_4 Scintillating Crystals." Nucl.Instr.Meth.A376. 203-207 (1997)

[文献書誌] M.Kobayashi,et al.: "Improvement in Transmittance and Decay Time of PbWO_4 Scintillating Crystals by La-doping." Nucl.Instr.Meth.A399. 261-268 (1997)

[文献書誌] S.Baccaro,et al.: "Influence of La^<3+> Doping on Radiation Hardness and Thermoluminescence Characteristics of PbWO_4" phys.stat.Sol.(a)16. R5-R6 (1997)

[文献書誌] M.Nikl et al.: "Decay Kinetics and Thermoluminescence of PbWO_4:La^<3+>" Appl.Phys.Letter.71(26). 3755-3757 (1997)

[文献書誌] M.Kobayashi,et al.: "Improvement of Radiation Hardness of PbWO_4 Scintillating Crystals by La-doping." Nucl.Instr.Meth.A404. 149-156 (1998)

[文献書誌] S.Baccaro,et al.: "Radiation Damage and Thermoluminescence of Gd-doped PbWO_4" Submitted to phys.Stat.Sol.,. (In press). (1997)

[文献書誌] M.Kobayashi,et al.: "Comparison of Radiation Damages of Different PbWO_4 Scintillating Crystals." Submitted to Nucl.Instr.Meth.,KEK Preprint. 97-144(In press). (1997.)

[文献書誌] V.V.Laguta,et al.: "Polaronic WO_4^<3-> Centers in PbWO_4 Single Crystals." J.Phys.Cond.Mat.,. (In press). (1998)

[文献書誌] K.Kurashige,et al.: "Mechanical Properties of a Gd_2SiO_5 Single Crystal." Japan,J.Appl.Phys.,. 36. 4122-2246. (1997)

[文献書誌] M.Tanaka,et al.: "Application of Cerium-doped Gadolinium Silicate Gd_2SiO_5:Ce Scintillator to Calorimeters in High Radiation Environment." Nucl.Instr.Meth.,. A404. 1998 (1998)

[文献書誌] H.Ishibashi,et al.: "Scintillation Performance of Large Ce-doped Gd_2SiO_5(GSO)Single Crystal." IEEE Nucl.Sci.Symp. & Medical Imag.Conf.Albuquerque,Nov.(In press). (1997)

[文献書誌] K.Kurashige,et al.: "Surface Polish of GSO Scintillator using Chemical Process," ibid.(In press). (1997)

[文献書誌] S.Yamamoto,et al.,: "A GSO Depth of Interaction Detector for PET." ibid.,. (In press). (1997)

[文献書誌] H.Murayama,et al.,: "A Depth Encoding in Multicrystal detector for PET." ibid.,. (In press). (1997)

[文献書誌] M.Kobayashi,et al.: "Large-size Bismuth Silicate(Bi_4Si_<13>O_<12>)Scintillating Crystals of Good Quality," Nucla.Instr.Meth.,. A400. 392-400 (1997)

[文献書誌] 寒川 真樹ほか: "BSO-BGO固溶体シンチレータ結晶の可能性." Proc.of Workshop on Scintillating Crystals,High Energy Accelerator Res.Organ.(KEK),Tsukuba. 49-56. (1997)

[文献書誌] 廣瀬 義朗ほか: "大型BSO(Bi_4Si_3O_<12>)単結晶の試作." Proc.of Workshop on Scintillating Crystals.57-64. (1997)

[文献書誌] H.Ishibashi,et al.,: "Large Ce-doped Gd_2SiO_5(GSO) Single Crystals 80 mm in Diameter." Pro.Workshop on Scintillating Crystals,ibid.69-71 (1997)

[文献書誌] H.Kurashige,et al.,: "Monte Carlo Simulation of Scintillator Efficiency for GSO Single Crystal." Pro.Workshop on Scintillating Crystals,ibid. 204-206 (1997)

[文献書誌] Y.Usuki,et al.,: "Proc.Workshop on Scintillating Crystals" Pro. Workshop on Scintillating Crystals,ibid. 207-216 (1997)

[文献書誌] M.Kobayashi,et al.,: "Recent Development in PbWO_4 Crystal Scintillators." Proc.Workshop on Scintillating Crystals,. 217-228 (1997)

[文献書誌] M.Ishii,et al.,: "Recent R&D on Oxide Scintillation Cryatals for Radiation Detectors." Proc.4^<th> Korea-Japan Electronic Materials Growth Symp.,Soul,. 131-134 (1997)

[文献書誌] M.Kobayashi.,et al.,: "Improvement in Scintillation Characteristics of PbWO_4 Scintillating Crystals by La-doping." SCINT'97,Proc.Inter.Conf.Inorganic Scintilators and Their Applications,Shanghai,P.R,China.Sept.22-25,1997.(In press). (1997)

[文献書誌] M.Tanaka,et al.,: "Stability of Ce doped Gd_2SiO_5(GSO) Scintillator under Irradiation." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] H.Ishibashi,et al.,: "Large Ce-Doped Gd_2SiO_5(GSO) Single Crystal 80 mm in diameter and its Performance." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] M.Nikl,et al.,: "Luminescence and Scintillation Decay Kinetics of PbWO_4 Single Crystals." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] S.Baccaro,et al.,: "Radiation Hardness Characteristics of PbWO_4 Single Crystals." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] M.Ishii,et al.,: "Growth and Characterization of Large BSO(Bi_4Si_3O_<12>) Crystals for Radiation Detectors." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] Fei Yiting,et al.,: "Phase Relation and Crystallization Behavior of Bi_2O_3-SiO_2 System." SCINT'97,ibid.,. (In press). (1997)

[文献書誌] Y.Usuki,et al.,: "Crystal Growth and Scintillation Characteristics of La doped PbWO_4 for High Energy Physics Experiments." Proc.Inter.Symp.Laser and Nonlinear Optical Materials,Singapore,Nov.3-5,1997,. 342-345 (1997)

[文献書誌] M.Kobayashi.,et al.,: "Scintillating Characteristics of Highly Concentrated Solid Soution Bal._xCexF_2+x with 0.1≦X≦0.45." SCINT'97,Proc.Inter.Conf.Inorganic Scintillators and Their Applications,Shanghai,P.R.China.Sept.22-25,1997.(In press). (1997)

[文献書誌] M.Kobayashi,et al.,: "Recent R&D Results on Heavy,Fast and Radiation-Hard Scintillating Crystals Based on Oxides." SSD-97,Yekaterinburg,Russia,Nov.28,1997.(In press). (1998)

[文献書誌] M.Kobayashi,et al.: "Scintillating Characteristics of Non-storichometric Phases Formed in MF_2-GdF_3-CeF_3 Systems with M=Ba,Sr and Ca." SSD-97,Yekaterinburg,Russia,Nov.28,1997.(In press). (1998)

[文献書誌] M.Kobayashi: "The PHOSPHORHANDBOOK (Ed.S.Shioya and W.M.Yen)" CRC Press,Inc., 541-550 (1998)

1997 年度実績報告書

石井満湘南工科大学, 工学部, 教授 (80212827)

[文献書誌] 寒川真樹ほか: "BSO-BGO固溶体シンチレータ結晶の可能性." Proc.of Workshop on Scintillating Crystals,High Energy Accelerator Res.Organ.(KEK),Tsukuba. 49-56. (1997)

[文献書誌] 廣瀬義朗ほか: "大型BSO(Bi_4Si_3O_<12>)単結晶の試作." Proc.of Workshop on Scintillating Crystals.57-64. (1997)