Development of BaF2 crystals for scintillators
Creators
- Fogel, William
- Institut National Polytechnique de Grenoble - INPG (France)
- Commissariat a l'energie atomique et aux energies alternatives - CEA, Centre d'Etudes Nucleaires de Grenoble, Service d'Etudes Analytiques, Section de Recherches et Controles Analytiques (France)
- CEA Grenoble, Division Leti (France)
Description
This paper concerns the elaboration by the Bridgman method of BaF2 crystals with the required properties (optical transparency and absence of gaseous inclusions) for scintillating applications. Absorptions in the near ultraviolet were linked to contaminations with oxygen anions and could be eliminated by a refining of the melted bath at about 200 deg. C above the fluoride fusion temperature. The presence of inclusions, due to the release of dissolved gases (argon of the atmosphere) at the time of solidification, was linked to oxygen pollutants and to certain crystal growth conditions (high solidification speed, large diameter of crystals). It could be avoided by a fluoride gas treatment of powders prepared by precipitation in aqueous environments.
Abstract (French)
Ce memoire concerne l'elaboration par la methode Bridgman de cristaux de BaF2 ayant les proprietes requises (transparence optique et absence d'inclusions gazeuses) pour application scintillateur. Les absorptions dans le proche ultra-violet ont ete reliees a des contaminations en anions oxygenes et ont pu etre eliminees par un affinage du bain fondu a environ 200 deg. C au dessus de la temperature de fusion du fluorure. La presence des inclusions, liberation de gaz dissous (argon de l'atmosphere de croissance) au moment de la solidification, a ete reliee d'une part a des polluants oxygenes, et d'autre part a certaines conditions de cristallogenese (vitesse de solidification elevee, grand diametre des cristaux). Elle a pu etre evitee par un traitement au fluor gazeux de poudres preparees par precipitation en milieux aqueux. Les cristaux ainsi elabores ont la qualite optique exigee pour etre employes comme scintillateurs. (auteur)Files
51109413.pdf
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Additional details
Additional titles
- Original title (French)
- Elaboration de cristaux de BaF2 pour scintillateurs
Publishing Information
- Imprint Pagination
- 198 p.
- Report number
- FRCEA-TH--12207
INIS
- Country of Publication
- France
- Country of Input or Organization
- France
- INIS RN
- 51109413
- Subject category
- S36: MATERIALS SCIENCE; S46: INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY;
- Resource subtype / Literary indicator
- Thesis
- Descriptors DEI
- ABSORPTION; BARIUM FLUORIDES; BRIDGMAN METHOD; CRYSTAL DEFECTS; CRYSTAL GROWTH; CRYSTALLIZATION; FABRICATION; INCLUSIONS; PHOSPHORS; POWDERS; REFINING; SOLID SCINTILLATION DETECTORS; ULTRAVIOLET RADIATION
- Descriptors DEC
- ALKALINE EARTH METAL COMPOUNDS; BARIUM COMPOUNDS; BARIUM HALIDES; CRYSTAL GROWTH METHODS; CRYSTAL STRUCTURE; ELECTROMAGNETIC RADIATION; FLUORIDES; FLUORINE COMPOUNDS; HALIDES; HALOGEN COMPOUNDS; MEASURING INSTRUMENTS; PHASE TRANSFORMATIONS; PROCESSING; RADIATION DETECTORS; RADIATIONS; SCINTILLATION COUNTERS; SORPTION
Optional Information
- Notes
- 58 refs.; Available from the INIS Liaison Officer for France, see the INIS website for current contact and E-mail addresses