Abstract
This thesis was performed in the context of a project aiming to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute. Two aspects have been studied: The detection and the polarization analysis of ultracold neutrons. Three types of detectors have been tested at the Institut Laue-Langevin (ILL): The Cascade-U (GEM technology), the {sup 3}He gas detector and {sup 6}Li-doped glass scintillators (GS family). Their detection efficiency and their background sensitivity have been measured. The GS10 scintillator is competitive with the {sup 3}He gas detector under the conditions realized with the EDM spectrometer. A GS3/GS20 scintillator stack has enabled to improve the neutron/gamma discrimination. It has been found 20% less efficient than the {sup 3}He gas detector under the EDM spectrometer. The Cascade-U detector has been observed to be 20% less efficient than a 500 microns thick GS10 glass as confirmed by simulations. A new system for simultaneous spin analysis is presented. It consists of two independent detection systems (arms) which are each made of an adiabatic spin flipper, a spin analyzer, and a detector. The arms detect opposite spin components, allowing the simultaneous counting of both neutron spin orientations. A prototype mounted in horizontal configuration
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Citation Formats
Rogel, Gwendal.
Development of ultracold neutron detectors and a polarization analyzing system for the measurement of the neutron electric dipole moment; Developpement de detecteurs de neutrons ultra-froids et d'un systeme d'analyse de polarisation pour la mesure du moment electrique dipolaire du neutron.
France: N. p.,
2009.
Web.
Rogel, Gwendal.
Development of ultracold neutron detectors and a polarization analyzing system for the measurement of the neutron electric dipole moment; Developpement de detecteurs de neutrons ultra-froids et d'un systeme d'analyse de polarisation pour la mesure du moment electrique dipolaire du neutron.
France.
Rogel, Gwendal.
2009.
"Development of ultracold neutron detectors and a polarization analyzing system for the measurement of the neutron electric dipole moment; Developpement de detecteurs de neutrons ultra-froids et d'un systeme d'analyse de polarisation pour la mesure du moment electrique dipolaire du neutron."
France.
@misc{etde_22630238,
title = {Development of ultracold neutron detectors and a polarization analyzing system for the measurement of the neutron electric dipole moment; Developpement de detecteurs de neutrons ultra-froids et d'un systeme d'analyse de polarisation pour la mesure du moment electrique dipolaire du neutron}
author = {Rogel, Gwendal}
abstractNote = {This thesis was performed in the context of a project aiming to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute. Two aspects have been studied: The detection and the polarization analysis of ultracold neutrons. Three types of detectors have been tested at the Institut Laue-Langevin (ILL): The Cascade-U (GEM technology), the {sup 3}He gas detector and {sup 6}Li-doped glass scintillators (GS family). Their detection efficiency and their background sensitivity have been measured. The GS10 scintillator is competitive with the {sup 3}He gas detector under the conditions realized with the EDM spectrometer. A GS3/GS20 scintillator stack has enabled to improve the neutron/gamma discrimination. It has been found 20% less efficient than the {sup 3}He gas detector under the EDM spectrometer. The Cascade-U detector has been observed to be 20% less efficient than a 500 microns thick GS10 glass as confirmed by simulations. A new system for simultaneous spin analysis is presented. It consists of two independent detection systems (arms) which are each made of an adiabatic spin flipper, a spin analyzer, and a detector. The arms detect opposite spin components, allowing the simultaneous counting of both neutron spin orientations. A prototype mounted in horizontal configuration has been tested at ILL. The analyzing power of both arms has been measured to be 80%. The transmission of the system without spin analyzers has been found to be 50%. (author) [French] Cette these s'inscrit dans un nouveau projet de mesure du moment dipolaire electrique (EDM) du neutron a l'institut Paul Scherrer. Deux aspects ont ete etudies ici: la detection et l'analyse de polarisation de neutrons ultra-froids. Trois types de detecteurs ont ete testes a l'Institut Laue-Langevin (ILL): le Cascade-U (technologie GEM), le compteur a gaz {sup 3}He et des scintillateurs dopes au {sup 6}Li (type GS). Leur efficacite de detection ainsi que leur sensibilite au bruit de fond ont ete mesurees. Sous les conditions experimentales du spectrometre EDM, le scintillateur GS10 s'est montre competitif avec le detecteur a gaz {sup 3}He. Un systeme de double scintillateur GS3/GS20 a permis d'ameliorer la separation entre signaux neutrons et gammas. Il s'est avere 20% moins efficace que le detecteur a gaz 3He sous le spectrometre EDM. Le Cascade-U a, quant a lui, montre qu'il etait 20% moins efficace qu'un GS10 de 500 microns d'epaisseur comme l'ont conrme des simulations. Un nouveau systeme d'analyse simultanee de spin est presente. Il consiste en deux systemes de detection (bras) possedant chacun un spin flipper adiabatique, un analyseur de spin, et un detecteur. Les bras detectent chacun une composante de polarisation, permettant ainsi un comptage des deux etats de spin du neutron. Des tests d'un prototype monte en situation horizontale a l'ILL ont montre que le pouvoir d'analyse des bras etait de 80%. La transmission du systeme sans analyseurs est de 50%. (auteur)}
place = {France}
year = {2009}
month = {Oct}
}
title = {Development of ultracold neutron detectors and a polarization analyzing system for the measurement of the neutron electric dipole moment; Developpement de detecteurs de neutrons ultra-froids et d'un systeme d'analyse de polarisation pour la mesure du moment electrique dipolaire du neutron}
author = {Rogel, Gwendal}
abstractNote = {This thesis was performed in the context of a project aiming to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute. Two aspects have been studied: The detection and the polarization analysis of ultracold neutrons. Three types of detectors have been tested at the Institut Laue-Langevin (ILL): The Cascade-U (GEM technology), the {sup 3}He gas detector and {sup 6}Li-doped glass scintillators (GS family). Their detection efficiency and their background sensitivity have been measured. The GS10 scintillator is competitive with the {sup 3}He gas detector under the conditions realized with the EDM spectrometer. A GS3/GS20 scintillator stack has enabled to improve the neutron/gamma discrimination. It has been found 20% less efficient than the {sup 3}He gas detector under the EDM spectrometer. The Cascade-U detector has been observed to be 20% less efficient than a 500 microns thick GS10 glass as confirmed by simulations. A new system for simultaneous spin analysis is presented. It consists of two independent detection systems (arms) which are each made of an adiabatic spin flipper, a spin analyzer, and a detector. The arms detect opposite spin components, allowing the simultaneous counting of both neutron spin orientations. A prototype mounted in horizontal configuration has been tested at ILL. The analyzing power of both arms has been measured to be 80%. The transmission of the system without spin analyzers has been found to be 50%. (author) [French] Cette these s'inscrit dans un nouveau projet de mesure du moment dipolaire electrique (EDM) du neutron a l'institut Paul Scherrer. Deux aspects ont ete etudies ici: la detection et l'analyse de polarisation de neutrons ultra-froids. Trois types de detecteurs ont ete testes a l'Institut Laue-Langevin (ILL): le Cascade-U (technologie GEM), le compteur a gaz {sup 3}He et des scintillateurs dopes au {sup 6}Li (type GS). Leur efficacite de detection ainsi que leur sensibilite au bruit de fond ont ete mesurees. Sous les conditions experimentales du spectrometre EDM, le scintillateur GS10 s'est montre competitif avec le detecteur a gaz {sup 3}He. Un systeme de double scintillateur GS3/GS20 a permis d'ameliorer la separation entre signaux neutrons et gammas. Il s'est avere 20% moins efficace que le detecteur a gaz 3He sous le spectrometre EDM. Le Cascade-U a, quant a lui, montre qu'il etait 20% moins efficace qu'un GS10 de 500 microns d'epaisseur comme l'ont conrme des simulations. Un nouveau systeme d'analyse simultanee de spin est presente. Il consiste en deux systemes de detection (bras) possedant chacun un spin flipper adiabatique, un analyseur de spin, et un detecteur. Les bras detectent chacun une composante de polarisation, permettant ainsi un comptage des deux etats de spin du neutron. Des tests d'un prototype monte en situation horizontale a l'ILL ont montre que le pouvoir d'analyse des bras etait de 80%. La transmission du systeme sans analyseurs est de 50%. (auteur)}
place = {France}
year = {2009}
month = {Oct}
}