Abstract
A 4{pi} anticoincidence, low-background counting system consisting of two specially designed parallel plate counters and a bridge anticoincidence circuit is described. Each counter is of a flat, mica window ''pancake'' type. The diameter of the counters is much larger than the gap between the plates. Good counting properties are obtained in spite of the unusual counter geometry, owing to the flexibility of the counter shape design when a neon-halogen mixture is used. The counters are so arranged that both windows face the sample, leaving a narrow slit for the sample holder. The sample is spread on a thin metalized plastic film. The pulses from both counters due to beta-particles coming from the sample are recorded, giving a 4{pi} counting geometry. The pulses due to cosmic particles triggering both counters simultaneously cancel out in a simple bridge anticoincidence arrangement, thus eliminating the need for an electronic circuit. Furthermore, the parallel plate counters used here for beta-particle counting possess a markedly reduced sensitivity to gamma-rays near the threshold voltage, resulting in a further lowering of the background. Sources of beta-particles of higher energies, as well as gamma-ray sources, can also be measured by the described system, because in the proposed geometry there
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Srdoc, D.
[1]
- Institute ''Ruder Boskovic'', Zagreb, Yugoslavia (Croatia)
Citation Formats
Srdoc, D.
A 4{pi} Anticoincidence Arrangement for Measurements of Beta-Ray Emitting Isotopes; Montage a Anticoiencidence 4{pi} pour la Mesure des Radioisotopes Emetteurs Beta; 4{pi} sistema schetchikov antisovpadenij dlya izmerenij beta-izluchayushchikh izotopov; Aparato de Recuento 4{pi} en Anticoincidencia para Medir Emisores Beta.
IAEA: N. p.,
1965.
Web.
Srdoc, D.
A 4{pi} Anticoincidence Arrangement for Measurements of Beta-Ray Emitting Isotopes; Montage a Anticoiencidence 4{pi} pour la Mesure des Radioisotopes Emetteurs Beta; 4{pi} sistema schetchikov antisovpadenij dlya izmerenij beta-izluchayushchikh izotopov; Aparato de Recuento 4{pi} en Anticoincidencia para Medir Emisores Beta.
IAEA.
Srdoc, D.
1965.
"A 4{pi} Anticoincidence Arrangement for Measurements of Beta-Ray Emitting Isotopes; Montage a Anticoiencidence 4{pi} pour la Mesure des Radioisotopes Emetteurs Beta; 4{pi} sistema schetchikov antisovpadenij dlya izmerenij beta-izluchayushchikh izotopov; Aparato de Recuento 4{pi} en Anticoincidencia para Medir Emisores Beta."
IAEA.
@misc{etde_22131304,
title = {A 4{pi} Anticoincidence Arrangement for Measurements of Beta-Ray Emitting Isotopes; Montage a Anticoiencidence 4{pi} pour la Mesure des Radioisotopes Emetteurs Beta; 4{pi} sistema schetchikov antisovpadenij dlya izmerenij beta-izluchayushchikh izotopov; Aparato de Recuento 4{pi} en Anticoincidencia para Medir Emisores Beta}
author = {Srdoc, D.}
abstractNote = {A 4{pi} anticoincidence, low-background counting system consisting of two specially designed parallel plate counters and a bridge anticoincidence circuit is described. Each counter is of a flat, mica window ''pancake'' type. The diameter of the counters is much larger than the gap between the plates. Good counting properties are obtained in spite of the unusual counter geometry, owing to the flexibility of the counter shape design when a neon-halogen mixture is used. The counters are so arranged that both windows face the sample, leaving a narrow slit for the sample holder. The sample is spread on a thin metalized plastic film. The pulses from both counters due to beta-particles coming from the sample are recorded, giving a 4{pi} counting geometry. The pulses due to cosmic particles triggering both counters simultaneously cancel out in a simple bridge anticoincidence arrangement, thus eliminating the need for an electronic circuit. Furthermore, the parallel plate counters used here for beta-particle counting possess a markedly reduced sensitivity to gamma-rays near the threshold voltage, resulting in a further lowering of the background. Sources of beta-particles of higher energies, as well as gamma-ray sources, can also be measured by the described system, because in the proposed geometry there is no possibility of triggering both counters simultaneously, as is the case with the conventional guard-counter arrangements. (author) [French] Le memoire decrit un ensemble de mesure a anticolhcidence 4{pi}, ayant un faible bruit de fond, compose de deux compteurs speciaux a plateaux paralleles relies par un pont d'anticofncidence. Ces deux compteurs sont de type circulaire plat a fenetre de mica. Le diametre du compteur est tres superieur a l'espace entre les plaques. Malgre sa geometrie inusitee, l'appareil a des proprietes de comptage satisfaisantes en raison de la souplesse que lui conferent ses caracteristiques lorsqu'on utilise un melange halogene-neon. Les compteurs sont disposes de maniere que les fenetres se trouvent l'une et l'autre en face de l'echantillon, un espace etroit etant menage pour le porte-echantillon. L'echantillon est etale sur une mince pellicule de matiere plastique metallisee. Les impulsions fournies par les deux compteurs en presence des particules beta provenant de l'echantillon sont enregistrees, donnant une geometrie de comptage 4{pi}. Les impulsions dues aux particules cosmiques actionnant les deux compteurs simultanement sont annulees par un simple dispositif d'anticofncidence a pont, ce qui supprime la necessite d'un circuit electronique selecteur. En outre, les compteurs a plateaux paralleles utilises pour la mesure des particules beta sont peu sensibles aux rayonnements gamma a proximite du seuil de tension, ce qui contribue a reduire encore le bruit de fond. Le montage decrit permet aussi de mesurer l'activite de sources beta de haute energie et de sources gamma, etant donne que la geometrie proposee empeche le declenchement simultane des deux compteurs, lequel se produit, par contre, dans les ensembles de comptage classiques a anneau de garde. (author) [Spanish] La memoria describe un aparato de recuento 4{pi} en anticoincidencia, de baja actividad de fondo, formado por dos contadores especiales de placas paralelas y un circuito de anticoincidencia en puente. Los contadores son del tipo 'oblea', planos, con ventana de mica. Su diametro es mucho mayor que el espacio que media entre las placas. Pese a la geometria peculiar de los contadores sus propiedades de recuento son satisfactorias gracias a la flexibilidad lograda al emplear una mezcla de neon y halogeno. Los contadores estan dispuestos de manera que ambas ventanas miran hacia la muestra, dejando una ranura estrecha para el portamuestras. La muestra se extiende sobre una delgada pelicula de material plastico metalizado. Se registran los impulsos que originan en ambos contadores las particulas beta emitidas por la muestra, obteniendose una geometria de recuento 4{pi}, Los rayos cosmicos disparan simultaneamente ambos contadores y los impulsos a que dan lugar se anulan en un sencillo dispositivo de anticoincidencia en puente, merced al cual se puede prescindir de un circuito electronico. Ademas, los contadores de placas paralelas que se emplean para el recuento de particulas beta poseen una sensibilidad notablemente reducida frente a los rayos gamma en las proximidades de la tension umbral, lo que aminora aun mas la actividad de fondo. El sistema descrito permite medir fuentes beta de energias mas elevadas y fuentes gamma dado que la geometria propuesta impide que ambos contadores sean disparados simultaneamente, como sucederia con los aparatos convencionales de contadores protegidos. (author) [Russian] Opisyvaetsja 4{pi} sistema schetchikov antisovpadenij s nizkim fonom, sostojashhaja iz 2 special'no skonstruirovannyh schetchikov s parallel'nymi plastinami i mostovoj shemy scheta antisovpadenij. Kazhdyj schetchik predstavljaet soboj plastinu so sljudjanym okoshkom, imejushhuju toroidal'no-diskovuju formu. Diametr schetchikov namnogo prevyshaet rasstojanie mezhdu plastinami. Poluchaetsja horoshaja schetnaja harakteristika, nesmotrja na neobychnuju geometriju schetchika, blagodarja gibkoj konstrukcii formy schetchika, kogda ispol'zuetsja neono-gelogennaja smes'. Schetchiki raspolagajut takim obrazom, chto oba okoshka obrashheny v storonu obrazca, pri jetom ostaetsja uzkaja shhel' dlja derzhatelja obrazca. Obrazec nanosjat na tonkuju plastmassovuju plenku s metallicheskoj osnovoj. Registrirujut impul'sy iz oboih schetchikov, voznikajushhie za schet beta-chastic, kotorye ispuskaet obrazec, v rezul'tate chego poluchaetsja 4{pi} geometrija scheta. Impul'sy za schet kosmicheskih chastic, zapuskajushhie oba schetchika odnovremenno, pogashajutsja v prostoj mostovoj sisteme schetchikov antisovpadenij i tem samym ustranjaetsja neobhodimost' v jelektronnoj sheme. Krome togo, schetchiki s parallel'nymi plastinami, kotorye ispol'zujutsja zdes' dlja scheta beta-chastic, imejut javno oslablennuju chuvstvitel'nost' k gamma-izlucheniju vblizi porogovogo naprjazhenija, v rezul'tate chego proishodit dal'nejshee snizhenie fona. Istochniki beta-chastic s bolee vysokimi jenergijami, a takzhe istochniki gamma-izluchenija mozhno tozhe izmerit' s pomoshh'ju opisannoj sistemy, poskol'ku v predlagaemoj geometrii otsutstvuet vsjakaja vozmozhnost' odnovremennogo zapuska oboih schetchikov, kak jeto imeet mesto v obychnyh sistemah schetchikov s blokirovkoj. (author)}
place = {IAEA}
year = {1965}
month = {Oct}
}
title = {A 4{pi} Anticoincidence Arrangement for Measurements of Beta-Ray Emitting Isotopes; Montage a Anticoiencidence 4{pi} pour la Mesure des Radioisotopes Emetteurs Beta; 4{pi} sistema schetchikov antisovpadenij dlya izmerenij beta-izluchayushchikh izotopov; Aparato de Recuento 4{pi} en Anticoincidencia para Medir Emisores Beta}
author = {Srdoc, D.}
abstractNote = {A 4{pi} anticoincidence, low-background counting system consisting of two specially designed parallel plate counters and a bridge anticoincidence circuit is described. Each counter is of a flat, mica window ''pancake'' type. The diameter of the counters is much larger than the gap between the plates. Good counting properties are obtained in spite of the unusual counter geometry, owing to the flexibility of the counter shape design when a neon-halogen mixture is used. The counters are so arranged that both windows face the sample, leaving a narrow slit for the sample holder. The sample is spread on a thin metalized plastic film. The pulses from both counters due to beta-particles coming from the sample are recorded, giving a 4{pi} counting geometry. The pulses due to cosmic particles triggering both counters simultaneously cancel out in a simple bridge anticoincidence arrangement, thus eliminating the need for an electronic circuit. Furthermore, the parallel plate counters used here for beta-particle counting possess a markedly reduced sensitivity to gamma-rays near the threshold voltage, resulting in a further lowering of the background. Sources of beta-particles of higher energies, as well as gamma-ray sources, can also be measured by the described system, because in the proposed geometry there is no possibility of triggering both counters simultaneously, as is the case with the conventional guard-counter arrangements. (author) [French] Le memoire decrit un ensemble de mesure a anticolhcidence 4{pi}, ayant un faible bruit de fond, compose de deux compteurs speciaux a plateaux paralleles relies par un pont d'anticofncidence. Ces deux compteurs sont de type circulaire plat a fenetre de mica. Le diametre du compteur est tres superieur a l'espace entre les plaques. Malgre sa geometrie inusitee, l'appareil a des proprietes de comptage satisfaisantes en raison de la souplesse que lui conferent ses caracteristiques lorsqu'on utilise un melange halogene-neon. Les compteurs sont disposes de maniere que les fenetres se trouvent l'une et l'autre en face de l'echantillon, un espace etroit etant menage pour le porte-echantillon. L'echantillon est etale sur une mince pellicule de matiere plastique metallisee. Les impulsions fournies par les deux compteurs en presence des particules beta provenant de l'echantillon sont enregistrees, donnant une geometrie de comptage 4{pi}. Les impulsions dues aux particules cosmiques actionnant les deux compteurs simultanement sont annulees par un simple dispositif d'anticofncidence a pont, ce qui supprime la necessite d'un circuit electronique selecteur. En outre, les compteurs a plateaux paralleles utilises pour la mesure des particules beta sont peu sensibles aux rayonnements gamma a proximite du seuil de tension, ce qui contribue a reduire encore le bruit de fond. Le montage decrit permet aussi de mesurer l'activite de sources beta de haute energie et de sources gamma, etant donne que la geometrie proposee empeche le declenchement simultane des deux compteurs, lequel se produit, par contre, dans les ensembles de comptage classiques a anneau de garde. (author) [Spanish] La memoria describe un aparato de recuento 4{pi} en anticoincidencia, de baja actividad de fondo, formado por dos contadores especiales de placas paralelas y un circuito de anticoincidencia en puente. Los contadores son del tipo 'oblea', planos, con ventana de mica. Su diametro es mucho mayor que el espacio que media entre las placas. Pese a la geometria peculiar de los contadores sus propiedades de recuento son satisfactorias gracias a la flexibilidad lograda al emplear una mezcla de neon y halogeno. Los contadores estan dispuestos de manera que ambas ventanas miran hacia la muestra, dejando una ranura estrecha para el portamuestras. La muestra se extiende sobre una delgada pelicula de material plastico metalizado. Se registran los impulsos que originan en ambos contadores las particulas beta emitidas por la muestra, obteniendose una geometria de recuento 4{pi}, Los rayos cosmicos disparan simultaneamente ambos contadores y los impulsos a que dan lugar se anulan en un sencillo dispositivo de anticoincidencia en puente, merced al cual se puede prescindir de un circuito electronico. Ademas, los contadores de placas paralelas que se emplean para el recuento de particulas beta poseen una sensibilidad notablemente reducida frente a los rayos gamma en las proximidades de la tension umbral, lo que aminora aun mas la actividad de fondo. El sistema descrito permite medir fuentes beta de energias mas elevadas y fuentes gamma dado que la geometria propuesta impide que ambos contadores sean disparados simultaneamente, como sucederia con los aparatos convencionales de contadores protegidos. (author) [Russian] Opisyvaetsja 4{pi} sistema schetchikov antisovpadenij s nizkim fonom, sostojashhaja iz 2 special'no skonstruirovannyh schetchikov s parallel'nymi plastinami i mostovoj shemy scheta antisovpadenij. Kazhdyj schetchik predstavljaet soboj plastinu so sljudjanym okoshkom, imejushhuju toroidal'no-diskovuju formu. Diametr schetchikov namnogo prevyshaet rasstojanie mezhdu plastinami. Poluchaetsja horoshaja schetnaja harakteristika, nesmotrja na neobychnuju geometriju schetchika, blagodarja gibkoj konstrukcii formy schetchika, kogda ispol'zuetsja neono-gelogennaja smes'. Schetchiki raspolagajut takim obrazom, chto oba okoshka obrashheny v storonu obrazca, pri jetom ostaetsja uzkaja shhel' dlja derzhatelja obrazca. Obrazec nanosjat na tonkuju plastmassovuju plenku s metallicheskoj osnovoj. Registrirujut impul'sy iz oboih schetchikov, voznikajushhie za schet beta-chastic, kotorye ispuskaet obrazec, v rezul'tate chego poluchaetsja 4{pi} geometrija scheta. Impul'sy za schet kosmicheskih chastic, zapuskajushhie oba schetchika odnovremenno, pogashajutsja v prostoj mostovoj sisteme schetchikov antisovpadenij i tem samym ustranjaetsja neobhodimost' v jelektronnoj sheme. Krome togo, schetchiki s parallel'nymi plastinami, kotorye ispol'zujutsja zdes' dlja scheta beta-chastic, imejut javno oslablennuju chuvstvitel'nost' k gamma-izlucheniju vblizi porogovogo naprjazhenija, v rezul'tate chego proishodit dal'nejshee snizhenie fona. Istochniki beta-chastic s bolee vysokimi jenergijami, a takzhe istochniki gamma-izluchenija mozhno tozhe izmerit' s pomoshh'ju opisannoj sistemy, poskol'ku v predlagaemoj geometrii otsutstvuet vsjakaja vozmozhnost' odnovremennogo zapuska oboih schetchikov, kak jeto imeet mesto v obychnyh sistemah schetchikov s blokirovkoj. (author)}
place = {IAEA}
year = {1965}
month = {Oct}
}