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Title: Scintillation materials for medical applications. Annual progress report, January 1, 1991--December 31, 1992

Abstract

Scintillators are beginning to attract renewed attention because modern High Energy Physics accelerators are placing unprecedented demands of quantity and quality of detector materials and Positron Emission Tomography (PET), used by the medical field. Both applications required materials for scintillator detectors with properties beyond those delivered by traditional scintillators. Thallium doped halides are very efficient, but slow and chemically unstable. Two modern developments, namely the very fast BaF{sub 2}, which owed its success to the newly discovered crossover transitions, and CeF{sub 3}, which carried a promise of fast components, more practical wavelengths and attractive efficiency. Since traditional scintillators (Tl doped halides) are very efficient, and could be even more efficient at larger concentrations of Tl, if it were not for concentration quenching. However Tl transitions are spin forbidden and slow. Both ills could be remedied by replacing Tl with Ce, whose transitions are allowed and which is known to form fully concentrated compounds of high photoluminescent efficiency and no quenching. These materials, plus new Ce-doped materials, exhibiting highly promising properties for medical applications, became the target of our studies.

Authors:
;
Publication Date:
Research Org.:
Boston Univ., MA (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10159424
Report Number(s):
DOE/ER/61033-3
ON: DE93015356
DOE Contract Number:
FG02-90ER61033
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: [1992]
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; 59 BASIC BIOLOGICAL SCIENCES; POSITRON COMPUTED TOMOGRAPHY; PHOSPHORS; CERIUM FLUORIDES; PHOSPHORESCENCE; CERIUM PHOSPHATES; LANTHANUM FLUORIDES; LANTHANUM PHOSPHATES; RARE EARTH COMPOUNDS; PROGRESS REPORT; COMPARATIVE EVALUATIONS; 550601; 550501; 550201; UNSEALED RADIONUCLIDES IN DIAGNOSTICS; TRACER TECHNIQUES

Citation Formats

Lempicki, A., and Wojtowicz, A.J. Scintillation materials for medical applications. Annual progress report, January 1, 1991--December 31, 1992. United States: N. p., 1992. Web. doi:10.2172/10159424.
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Lempicki, A., & Wojtowicz, A.J. Scintillation materials for medical applications. Annual progress report, January 1, 1991--December 31, 1992. United States. doi:10.2172/10159424.
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Lempicki, A., and Wojtowicz, A.J. Thu . "Scintillation materials for medical applications. Annual progress report, January 1, 1991--December 31, 1992". United States. doi:10.2172/10159424. https://www.osti.gov/servlets/purl/10159424.
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@article{osti_10159424,
title = {Scintillation materials for medical applications. Annual progress report, January 1, 1991--December 31, 1992},
author = {Lempicki, A. and Wojtowicz, A.J.},
abstractNote = {Scintillators are beginning to attract renewed attention because modern High Energy Physics accelerators are placing unprecedented demands of quantity and quality of detector materials and Positron Emission Tomography (PET), used by the medical field. Both applications required materials for scintillator detectors with properties beyond those delivered by traditional scintillators. Thallium doped halides are very efficient, but slow and chemically unstable. Two modern developments, namely the very fast BaF{sub 2}, which owed its success to the newly discovered crossover transitions, and CeF{sub 3}, which carried a promise of fast components, more practical wavelengths and attractive efficiency. Since traditional scintillators (Tl doped halides) are very efficient, and could be even more efficient at larger concentrations of Tl, if it were not for concentration quenching. However Tl transitions are spin forbidden and slow. Both ills could be remedied by replacing Tl with Ce, whose transitions are allowed and which is known to form fully concentrated compounds of high photoluminescent efficiency and no quenching. These materials, plus new Ce-doped materials, exhibiting highly promising properties for medical applications, became the target of our studies.},
doi = {10.2172/10159424},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 31 00:00:00 EST 1992},
month = {Thu Dec 31 00:00:00 EST 1992}
}
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Technical Report:
View Technical Report (0.51 MB)
DOI:  10.2172/10159424
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