Calibration of scintillation crystals for air kerma rate castle
-
Upload
leishman-associates -
Category
Technology
-
view
477 -
download
1
Transcript of Calibration of scintillation crystals for air kerma rate castle
CALIBRATION OF SCINTILLATION CRYSTALS FOR AIR KERMA RATE
Loch Castle, Scott Muston, Stephen Marks and Dr Stephen [email protected]
2
DETECTOR BASICS
Scintillation Crystal PMT MCA
GPS
PC
INTEGRATED ARPANSA GAMMA MAPPING SYSTEM (AGMS)
N
E
γ
3
SOFTWARE INTERFACE
4
MAPPING PRODUCTS
5
SCINTILLATION CRYSTAL TYPES
1x4 inch LaBr
(Lanthanum Bromide)
6x4 inch NaI
(Sodium Iodide)
4x4x16 inch NaI
(Sodium Iodide)
6
CONTRIBUTING RADIATION COMPONENTS
TERRESTRIAL
COSMIC
INTERNAL CONTAMINATIONSOURCE
7
DOSE RATE – AIR KERMA RELATIONSHIP
ii ENDdetDdet(Absorbed Dose in Detector)
Air Kerma Kair(Absorbed Dose in Air) nnn
nnair
ENwENwENwDwDwDwK
......
222111
2211
1keV = 1.6 x 10‐16J
8
ENERGY RESPONSE
SCINT
9
REGIONS OF INTEREST
SCINT
10
SOURCES COVERING THE REGIONS OF INTEREST
241Am 57Co 137Cs133Ba 60Co
SCINT
11
LINKING SOURCE AIR KERMA RATES
Source Air Kerma Rate Γδ(uGy.m-2.GBq-1.h-1)
241Am 3.58957Co 13.074133Ba 47.178137Cs 75.86160Co 306.400
12
SHADOW‐SHIELD TECHNIQUE
13
RESIDUAL PHOTOPEAK RELATES TO AIR KERMA RATE
14
ORIGINAL SETUP BY GRASTY ET AL
15
ARPANSA SETUP
16
SOLVING CALIBRATION COEFFICIENTS
wn = nGy.h-1/keV.s-1
17
AIR KERMA RATE COEFFICIENTS
18
TERRESTRIAL MEASUREMENTS
19
CARI‐6 COSMIC MEASUREMENTS
20
COSMIC SPECTRA
21
INTERNAL CONTAMINATION
22
INTERNAL CONTAMINATION
23
COMPONENT AIR KERMA RATES
24
CORRECTION FACTORS
25
CONFIRMATION OF RESULTS
26
END RESULT
27
QUESTIONS
28
PHOTOS
29
PHOTOS
30
PHOTOS