Conference papers
Implementation of an imaging spectrometer for localization and identification of radioactive sources
Abstract : Spatial localization of radioactive sources is currently a main issue interesting nuclear industry as well as homeland security applications, and can be achieved using gamma cameras. For several years, CEA LIST has been designing a new system, called GAMPIX, with improved sensitivity, portability and ease of use. The main remaining limitation is the lack of spectrometric information, preventing radioactive materials identification.
This article describes the development of an imaging spectrometer based on the GAMPIX technology. Experimental tests have been carried out according to both spectrometric methods enabled by the pixelated Timepix readout chip used in the GAMPIX gamma camera. The first method is based on the size of the impacts produced by a gamma-ray energy deposition in the detection matrix. The second one uses the Time over Threshold (ToT) mode of the Timepix chip and deals with time spent by pulses generated by charge preamplifiers over a user-specified threshold. Both energy resolution and sensitivity studies proved the superiority of the ToT approach that will consequently be further explored. Energy calibration, tests of several pixel sizes and use of the Medipix3 readout chip are tracks to improve performances of the newly implemented imaging spectrometer.
Keywords :
Calibration
imaging spectrometer
Sensitivity
Cameras
Time over Threshold
Timepix
GAMPIX
Gamma imaging
Detectors
Dispersion
national security
nuclear electronics
preamplifiers
radioactive sources
readout electronics
spectrometers
imaging spectrometer implementation
radioactive source localization
radioactive source identification
radioactive sources spatial localization
nuclear industry
homeland security applications
CEA LIST
system design
spectrometric information limitation
radioactive materials identification
imaging spectrometer development
GAMPIX technology
experimental tests
spectrometric methods
pixelated Timepix readout chip
GAMPIX gamma camera
impact size
gamma-ray energy deposition
detection matrix
time over threshold mode
ToT mode
pulse time spent
charge preamplifiers
user-specified threshold
energy resolution
energy sensitivity
ToT approach superiority
energy calibration
pixel size tests
Medipix3 readout chip
newly implemented imaging spectrometer improve performances
Cited literature [33 references]
http://hal.in2p3.fr/in2p3-00840026
Contributor : Sandrine Guesnon <>
Submitted on : Friday, May 3, 2019 - 8:35:05 AM
Last modification on : Monday, February 10, 2020 - 6:14:14 PM
Long-term archiving on: : Wednesday, October 9, 2019 - 12:26:19 PM
Contributor : Sandrine Guesnon <>
Submitted on : Friday, May 3, 2019 - 8:35:05 AM
Last modification on : Monday, February 10, 2020 - 6:14:14 PM
Long-term archiving on: : Wednesday, October 9, 2019 - 12:26:19 PM
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