DESY - August 7th 2007, Hamburg, Germany 1 Optically Stimulated Luminescence Dosimetry Based on SrS:Ce,Sm Phosphor for High-Energy Physics Applications 1 « RADIAtions et Composants » Research Group Institut d’Électronique du Sud (IES), University of Montpellier II, Montpellier, FRANCE 2 CERN, Geneva, SWITZERLAND D. Benoit 1 , F. Ravotti 1,2 , P. Garcia 1 , J-R. Vaillé 1 , and L. Dusseau 1
13
Embed
Optically Stimulated Luminescence Dosimetry Based on SrS ...
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
DESY - August 7th 2007, Hamburg, Germany 1
Optically Stimulated Luminescence Dosimetry
Based on SrS:Ce,SmPhosphor for High-Energy
Physics Applications
1 « RADIAtions et Composants » Research GroupInstitut d’Électronique du Sud (IES), University of Montpellier II, Montpellier, FRANCE
2 CERN, Geneva, SWITZERLAND
D. Benoit1, F. Ravotti1,2, P. Garcia1, J-R. Vaillé1, and L. Dusseau1
DESY - August 7th 2007, Hamburg, Germany 2
Why OSL ? A bit of History…1950/1960: first suggestion of OSL as a dosimetry tool80’s years:
OSL technique became popular in archeological and geological dating communityDevelopment of OSL imaging technique
In Montpellier80’s years: first research program on OSL phenomenon90’s years: development of OSL materialsConception of dosimeters and developments of applications1998: first paper on OSL dose-mapping2001: first paper on integrated OSL sensor2007: first accepted paper on OSL fibered dosimetry system for RADECS Conference
FeaturesBroad dynamic range: 6 decadesDetection threshold: 10 µGyLinear response with dose up to 500 Gy
OSL Material: SrS:Ce,SmMATERIAL PROPRIETIES
Raw OSLDifferent packagingIntegrated OSL sensor(grain size ~ few 100 µm)OSL Films (grain size ~50 µm)OSL deported by optical fibre(cylindrical shape with a diameter ~900 µm)
Calibration with High Energy X-raysON-LINE DOSIMETRY
Fibre #02 (25 m) Fibre #03 (15 m)UPM (V)
Sensitivity(mV.cGy-1)
0.5 V 0.8 V 0.5 V 0.8 V
4.19 81.9 3.84 74.5
0 1 2 3 4 5 60,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
4,0
4,5
5,0
OS
L S
igna
l (V
)
Dose (Gy)
Fibre n°03. UPM = 0.5 V Fibre n°03. UPM = 0.8 V Fibre n°02. UPM = 0.5 V Fibre n°02. UPM = 0.8 V
Good Linearity up to 6 Gy for the two optical fibres
DESY - August 7th 2007, Hamburg, Germany 12
PrincipleThermal and epithermal neutrons: OSL+B2O3
Fast neutrons: OSL+PERecoil protons following elastic scattering
First Results of two different neutrons fields
OSL Neutron-Sensitive Material
α+→<+ LieVEnB th710 )5.0(
MATERIAL DEVELOPMENT
First measurements match very well with the facility spectra
FACILITIES NEUTRON SPECTRA
OSL+B OSL+PE
CERN IRRAD2Ljubljana TRIGA Reactor
DESY - August 7th 2007, Hamburg, Germany 13
Conclusions & OutlookOSL dosimetry
Interesting properties (sensitivity, dynamics, linear response with dose)OSL Films: spatial distribution of the doseOSL Fibered dosimetry system: real-time measurements in harsh environment
AdvantagesMaterial Advantages
Not needed to heat the sample (Optical readout)High Radiation Hardness
Optical Fibre AdvantagesInsensitive to electro-magnetic interferences
Possibility to build compact, low cost and flexible systems
OutlookComplete characterization of the system ongoing Comparison of results with others dosimetric tools