DESIGN OF THE LOCAL GAMMA COUNTER SHIELD FOR THE INSTALLATION - - PowerPoint PPT Presentation
DESIGN OF THE LOCAL GAMMA COUNTER SHIELD FOR THE INSTALLATION INTENDED FOR THE IDENTIFICATION OF HIDDEN EXPLOSIVES AND DRUGS Participants: Supervisor: Michal Kesina , Ekaterina Lesovaya, University of West Bohemia in Pilsen Joint Institute
Supervisor: Ekaterina Lesovaya, Joint Institute for Nuclear Research in Dubna Participants: Michal Křesina, University of West Bohemia in Pilsen Anna Borkowska Michał Nowakowski Jagiellonian University in Cracow
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Design of the local gamma counter shield...
en.wikipedia.org siliconangle.com www.pittsburghcoalitionforsecurity.org
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Design of the local gamma counter shield...
Airport scanners Complex for monitoring vehicles Mobile complex
Variants for detecting hidden drugs and explosives “Rapiscan Systems” (USA)
1 2 3 4 5 6 7 8 9 50 100 150 200
4.44 MeV cross section, mbarn Е, MeV
12C 1 2 3 4 5 6 7 8 9 20 40 60 80 100 120 140 160 180
7.12 6.92 6.13 4.44 3.86 3.69 3.09 2.75 1.76 cross section, mbarn Е, MeV
16O
1 2 3 4 5 6 7 8 9 10 20 30 40 50 60
2.13 3.09 6.1 6.45 6.73 7.03 5.11 4.44 3.86 3.69 2.32 1.64 cross section, mbarn Е, MeV
14NGamma ray lines produced by 14.1 MeV neutron irradiation of carbon, nitrogen and oxygen
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Design of the local gamma counter shield...
www.wisegeek.com
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Design of the local gamma counter shield...
The calculations have been carried
(MC)-based MCNP4C code. The MCNP code, developed and maintained by Los Alamos National Laboratory, is the internationally recognized code for the MC analysis of neutron and gamma ray transport (hence NP for neutral particles).
greatlakesgeomatics.com
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Design of the local gamma counter shield...
Mode n p IMP:n,p 1 1 0 1 0 1 1 SDEF cel=4 pos=0.01 0 0 vec=1 0 0 dir=d1 par=1 erg=14 wgt=5e+6 SI1 0 1 SP1 0 1 M1 6000.60c 0.3333 1001.60c 0.6667 $ Polyethylene M3 82000.60c 1 $ Pb-nat M2 26000.50c 1 $ Fe-nat F1:n (7 8 9) 7 fq1 e f F11:p (7 8 9) 7 fq11 e f E1 1e-9 1.585e-9 2.512e-9 3.981e-9 6.31e-9 1e-8 1.585e-8 2.512e-8 3.981e-8 6.31e-8 1e-7 1.585e-7 2.512e-7 3.981e-7 6.31e-7 1e-6 1.585e-6 2.512e-6 3.981e-6 6.31e-6 1e-5 1.585e-5 2.512e-5 3.981e-5 6.31e-5 1e-4 1.585e-4 2.512e-4 3.981e-4 6.31e-4 1e-3 1.585e-3 2.512e-3 3.981e-3 6.31e-3 1e-2 1.585e-2 2.512e-2 3.981e-2 6.31e-2 1e-1 1.585e-1 2.512e-1 3.981e-1 6.31e-1 1e-0 1.585e-0 2.512e-0 3.981e-0 6.31e-0 1e+1 11 12 13 13.9 14 E11 0.5 474i 10 4i 20 NPS 2000000000 CTME 60 c ===cells=== 1 2 -7.8 1 -12 -5 6 2 -4 $ Fe 2 2 -7.8 11 -13 -5 6 2 -4 3 0 -7 9 -8 $ BGO 4 0 -10 (-1:3:5:-6:-2:4) (7:8:-9) 5 0 10 6 2 -7.8 12 -11 -5 6 2 -4 7 2 -7.8 13 -3 -5 6 2 -4 c ===== SURFACES ==== 1 px 5 2 p 0.15 1 0 0 3 px 30 4 p -0.15 1 0 0 5 p -0.15 0 1 0 6 p 0.15 0 1 0 7 c/z 33.82 0 3.81 8 pz 3.81 9 pz -3.81 10 so 100 11 px 17.5 12 px 11.25 13 px 23.75
Monte Carlo simulations for the
for gamma-detector cell card- used to specify volume surface card- used to specify surfaces geometry data card- contains any data that is needed for the problem
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Design of the local gamma counter shield...
L/2 2 4,5,6 x y z 5 cm L/4 L=25 cm, 35 cm, 45 cm 7.62 cm 3.81 cm 12 1 11 13 3 9 7 8 BGO S 1 6 2 7 Homogenous shield Polyethylene (CH2, ρ=0.94 g/cm3) Iron (Fe, ρ=7.8 g/cm3) Lead (Pb, ρ=11.4 g/cm3) Heterogeneous shield CH2- Fe and Fe- CH2 CH2- Pb and Pb- CH2
1E-9 1E-6 1E-3 1 0.01 0.1 1 10 100 1000
Polyethylene Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
1E-3 0.1 10 0.1 1 10 100 1000
25 cm 35 cm 45 cm Iron Number of neutrons in the bin E[MeV]
0.01 0.1 1 10 0.1 1 10 100 1000
Lead Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
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Design of the local gamma counter shield...
Fe Pb Pol
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Design of the local gamma counter shield...
Fe Pb
1E-9 1E-6 1E-3 1 0.01 0.1 1 10 100 1000
Lead-Polyethylene
Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
1E-3 1 1E-3 0.01 0.1 1 10 100 1000
Polyethylene-Lead
Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
1E-9 1E-6 1E-3 1 0.01 0.1 1 10 100 1000
Iron-Polyethylene
Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
1E-6 1E-4 0.01 1 1E-3 0.01 0.1 1 10 100 1000
Polyethylene-Iron
Number of neutrons in the bin E[MeV] 25 cm 35 cm 45 cm
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Design of the local gamma counter shield...
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Design of the local gamma counter shield...
1 2 3 4 5 6 7 4 8 12 16 18
Iron Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
1 2 3 4 5 6 2 4 10.0 10.2 10.4 10.6 10.8 11.0
Lead Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
1 2 3 4 5 6 0.00 0.05 0.10 0.15 0.20 0.25 120 130
Polyethylen Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
Fe Pb Pol
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Design of the local gamma counter shield...
Pb Fe
1 2 3 4 5 6 7 8 9 10 3 6 34
Iron - Polyethylen Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
1 2 3 4 5 6 2 45 54
Lead - Polyethylen Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
1 2 3 4 5 6 7 8 9 10 20 45.0 45.5 46.0 46.5 47.0 47.5 48.0
Polyethylen - Iron Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
1 2 3 4 5 6 2 4 6 16 18
Polyethylen - Lead Number of gamma rays in the bin E [MeV] 25cm 35cm 45cm
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Design of the local gamma counter shield...
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Design of the local gamma counter shield...
and heterogeneous shields made of CH2, Fe, Pb, and their combinations with a thickness of 25, 35, and 45 cm towards the gamma-spectrometer. The neutrons hitting the shielding had an energy
number of background counts.
5.11 MeV 14N,6.13 16O).
and γ rays because:
by the last layer of the shield matter.
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Design of the local gamma counter shield...
http://homepages.cae.wisc.edu/~bohm/neep412/lucasMCNPTutorialspring2010.pdf
Version 5, 24 April 2013, http://www.nucleonica.net/wiki/images/8/89/MCNPvolI.pdf
www.creativindie.com
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Design of the local gamma counter shield...