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Hassan
Amany
Noura
Ahmed
Ali
HANAA* Humans Applying Neutron Activation Analysis
Material Analysis Using Characteristic Gamma Rays from Neutron Induced Nuclear Reactions
Ahmed Abd Elfatah Elhoushy, Nuclear Engineer, Alexandria University, Faculty of Engineering,
Nuclear & Radiation Engineering Department, Prompt Gamma Neutron Activation Analysis in
Mining
Yasser Farrag Ali, Biophysics Laboratory, Physics Dept., Faculty of science, Al-Azhar University,
Shielding of BGO probe from 239Pu-Be neutron-gamma radiation
Noura Hassan, Assistant Lecturer in physics, Faculty of Engineering, Egyptian Russian University,
Feasibility study of humidity of furnace coke by neutrons
Ahmed Mohamed Hassan, Assistant Lecturer, Physics Department, Faculty of Science, Mansoura
University, Measurements of gamma-ray activity of environmental samples from Egypt
Neutron & Gamma
ray Spectrometry
Amany Hamdy Abdullah, Radioactive Isotopes Production Facility, Egyptian Atomic Energy
Authority ETRR-2, Optimizing the shielding of TANGRA NaI(Tl) array
* HANAA means:
Happiness, Bliss, Felicity,
Joy, Peace,….
Measurements of gamma-ray activity of environmental
samples from Egypt
By
Mr/ Ahmed Hassan
Assistant lecturer, Mansoura university, Egypt
Supervision: Dr. Ivan Ruskov, Senior scientist, FLNP
Mr. Constantin Hramko, engineer, FLNP
Aim of the work.
Experimental work.
Sample Preparation and HpGe setup.
Results and discussion.
Conclusions.
References.
Outline
Study of activity concentration of natural radionuclides such
as 226Ra , 232Th and 40K around this area in plant samples to evaluate the potential health hazards on general public.
The Problem
Contamination process due to production operation of certain
components that contain hazard materials around fertilizer
factories area.
Experimental work (samples locations and
preparation)
Plant sample
Washing
Drying
Powder Polyethylene
Container 4W Counting
Results and discussion
This figure shows the variation of
activity concentrations of 226Ra and 232Th at different positions.
This figure shows the variation of
activity concentrations of 40K at
different positions.
The obtained results illustrate the following
observation, the study area is still in the zones of
normal radiation level except position P1L which
are higher than the permissible maximum values
for indoor and outdoor exposures .
It was recommend to avoid this area for public
health.
Conclusions
References
Assessment the shielding property of iron for BGO scintillation detector from 239Pu-Be
neutron source
Shielding of scintillation detectors from direct penetration of neutrons from the source. Especially, when there is willing to study the interaction of fast neutron with medium and heavy nuclei “detect secondary nuclear radiation (neutrons and gamma quanta)”
Elastic scattering Inelastic scattering
Neutron capture
Compound nucleus
239PuBe
Neu
tro
n S
ourc
e
Spontaneous fission of heavy nuclides
Isotopic neutron source
Based on (γ,n) and (α,n) reaction in beryllium
BGO (Ø76 x 65 mm)
Data acquisition system (DAQ): MCA ADCM
and its software main panel LINUX operation system
ADCM – digitizing of the
analog signals and store the
time-amplitude of each of them
in list-mode (one-by-one)
(.DAT)
C++ ROMANA and
TOFANA – analyze the list-
mode .DAT files and create
.ROOT files containing the
histograms (Energy- and Time-
distributions) of the recorded
events.
ROOT scripts – for calculation
of channel-energy calibration
curves and determine the
efficiency of gamma-ray
detectors.
ADCM16-LTC, 16-channel/ 14-bit/100MHz,
ADC-boards from AFI™ Electronics.
Iron of thickness at least 30 cm compared to lead allows
one to achieve the highest suppression factors at for the
count rate.
Based on these results, It is recommended to use iron
instead of lead, because it has many advantages:
• Cheap.
• Has less mass than lead.
By
Amany Hamdy Abdullah
Optimizing the shielding of
TANGRA NaI(Tl) array
Supervisor
Dr. Ivan Ruskov, senior scientist @ FLNP
TANGRA (TAgged Neutrons & Gamma RAys)
TANGRA-project has been recently started in
Frank Laboratory of Neutron Physics (FLNP) of
the Joint Institute for Nuclear Research (JINR)
in Dubna to study some important for
fundamental and applied nuclear physics
reactions (n,n), (n,n'γ), (n,2n), (n,f), (n,gf),
induced by 14.1 MeV neutrons.
Main components:
In the frame of TANGRA-project some experimental
work was done in order to choose the optimum type and
thickness of a shielding to protect NaI(Tl) scintillation
gamma-ray detectors from the ING-27 direct 14.1 MeV
neutrons.
Data acquisition system (DAQ)
LINUX operation system
ADCM – digitizing of the
analog signals and store the
time-amplitude of each of
them in list-mode (one-by-
one) (.DAT)
C++ ROMANA and
TOFANA – analyze the list-
mode .DAT files and create
.ROOT files containing the
histograms (Energy- and
Time-distributions) of the
recorded events.
ROOT scripts – for
calculation of channel-energy
calibration curves and
determine the efficiency of
gamma-ray detectors.
MCA ADCM and its software main panel
The objective of this study was to investigate the
shielding effectiveness of different combination
of layers from lead (Pb), iron (Fe), polyethylene
(PE) and/or borated polyethylene (BPE)
Experimental setup
The shields, composed from layers of different materials,
was positioned between the neutron generator ING-27
and the investigated hexagonal NaI(Tl) scintillation
probe as shown below.
Number of events No and Nd was determined from
the corresponding gamma-ray pulse-height spectra
(number of events per amplitude channel) as a
function of the light output (LO) of the NaI(Tl)
scintillator in MeVee units (equivalent to 1 MeV
electron light output).
Experimental results
Fig. 4. Amplitude distributions of events recorded by NaI(Tl) probe
located behind 10, 20, 30, 40 and 50 cm thick Fe shields, compare with
that of the bare probe, in the NaI(Tl) scintillator light output interval of
LO = 2.0 6.9 MeVee.
2.4 3.2 4.0 4.8 5.6 6.40
2
4
6
8
10 Fe, d
0 cm
10 cm
20 cm
30 cm
40 cm
50 cm
Num
ber o
f eve
nts (
x103 )
Amplitude (MeVee)
Fig. 5. Amplitude distributions of events recorded by NaI(Tl)
probe behind 50 cm thick Fe and Pb shields in the interval of
LO = 2.8 6.9 MeVee. The lowest light output limit was LO =
0.2 MeVee.
2.8 3.6 4.4 5.2 6.0 6.83.2 4.0 4.8 5.6 6.4
200
400
600
800
1000
1200
1400N
umbe
r of
eve
nts
Amplitude (MeVee)
50 cm Fe
50 cm Pb
Fig. 6. Amplitude spectra of events recorded by NaI(Tl) probe behind
50 cm thick.
2.8 3.2 3.6 4.0 4.4 4.8 5.2 5.6 6.0 6.4 6.8
200
400
600
800
1000
1200
1400
Nu
mb
er o
f ev
ents
Amplitude (MeVee)
Fe(40cm)+BPE(10cm)
Fe(30cm)+BPE(10cm)+Pb(10cm)
Fe(20cm)+BPE(10cm)+Pb(20cm)
Fe(10cm)+BPE(10cm)+Pb(30cm)
From Fig.6 one can conclude that
a) In the presents of BPE it is important to have
additional heavy metal shield before NaI(Tl) to
suppress gamma-rays from the interaction of the
moderated (by Fe) neutrons with the BPE-nuclei
and
b) In the case of triple-layer shields, the
complementary thicknesses of Fe and Pb shown
the same level of suppression in the range of
experimental data uncertainties.
Discussion and conclusions A shield with both Fe and BPE could be more effective than just
Fe or BPE alone, because the advantages of both Fe and BPE are
utilized. Iron (Fe) is effective in slowing down high-energy
neutrons (e.g., 14-MeV source neutrons) and attenuating gammas,
while hydrogen of BPE is effective in slowing down fast neutrons
(till a few MeV), and 10B has a high absorption cross section for
thermal neutrons and a low production yield of gammas. So, a
shield made of 30cm Fe followed by a 20 cm BPE-layer can
meet the goal.
According to the experimental results obtained in this
methodological work, three layer shields made of
Fe(30cm)+BPE(10cm)+Pb(10cm) or
Fe(20cm)+BPE(10cm)+Pb(20cm) provided the highest
suppression factors on the hexagonal NaI(Tl) gamma-ray detector
load.
Thank you for your attention
2012
By
Noura Hassan Ibrahim
Physics Demonstrator , ERU
Under Supervision
Prof. Dr. Samir Yousha El-Khamessy
Professor of Nuclear Physics, Physics Dep. , ASU
Dr. Hesham Ibrahim Shahbunder
Assistant Professor of Nuclear Engineering, Physics Dep., ASU
Dr. Ashraf Hamed
Assistant Professor
By
Assistant Lecturer, Faculty of Engineering, Egyptian Russian University
Under supervision
Senior scientist @ Frank Laboratory of Neutron Physics, JINR
OUTLINE
Introduction
Neutron and Gamma-ray Spectrometry.
Literature review.
Aim of the work.
Methodology.
Experimental set-up.
Results & Conclusion.
39
Introduction 40
Gamma-ray spectrometry is an analytical method that allows the identification and quantification of gamma emitting isotopes in a variety of matrices.
Neutron and Gamma-ray Spectrometry 41
Literature Review
A. El Abd; A method for moisture measurement in porous media based on epithermal neutron scattering; Applied Radiation and Isotopes; 2015.
P. Peter; In-Situ element analysis from gamma-ray and neutron spectra using a pulsed neutron source; University of Groningen; 2010.
A. Anaqvi; Moisture measurements of wood and sugar samples using neutron transmission technique; Nuclear instruments and methods in physics research; 2003.
R. Ziemer; Effects of neutron source type on soil moisture measurement; USDA-Cal.
I. Goldeberg, et. al.; measurement of moisture content and density of soil masses using radioactive methods; LUNAR
42
Literature Review 43
Study the possibility of determining the humidity of
furnace coke using 239Pu-Be source
Aim of the Present Work 44
• The proposed method for determining the humidity
of a test sample by the analysis of spectra of prompt
gamma rays that emitted from the test sample after
irradiated by fast neutron.
• The humidity of test sample can be determined from
the characteristic gamma lines of Hydrogen and
Oxygen.
Methodology 45
Interaction of neutron with water 46
Fig. 1: Interaction of Neutron with Nucleus
Neutron capture Fast neutron Inelastic scattering
1H(2223.25 KeV)
16O(6129 KeV)
Experimental Setup
239Pu-Be source (A=5*106n/s)
BGO scintillation detector
Combined shielding bricks
(Fe + Bi).
A computerized 16-channel read out system.
47
Experimental Setup
LINUX operation system ADCM – digitizing of the analog signals and store the time-amplitude of each of them in list-mode (one-by-one) (.DAT) C++ ROMANA and TOFANA – analyze the list-mode .DAT files and create .ROOT files containing the histograms (Energy- and Time-distributions) of the recorded events. ROOT scripts – for calculation of channel-energy calibration curves and determine the efficiency of gamma-ray detectors.
48
Data acquisition system (DAQ): MCA
ADCM and its software main panel
A 2 kg coke sample, containing a variable
amount of water (from 2% up to 80%), was
irradiated with 239Pu-Be neutrons every time for
10 hours
Results and Discussion 49
Results 50
Results 51
Results 52
These measurements show that it is possible to
determine the amount of water, added into the
coke sample, analyzing the characteristic
gamma-ray spectra.
Conclusion 53
54
Prompt-gamma neutron activation analysis in mining
By
Ahmed Abd El fatah Elhoushy Nuclear Engineer ,Faculity Of Engineering, Alexandria University
Supervisor
Dr / Ivan Ruskov Senior Scientist , Frank Laboratory Of Neutron Physics
Outline
• Introduction
• Experimental work
• Results and discussion
• Conclusions
Introduction • What is Neutron Activation
Analysis (NAA)?
NAA is a method for qualitative and quantitative determination of elements based on the measurement of characteristic radiation from radionuclides formed by neutron irradiation of the material.
• According to type of emitted γ-ray measured
If the Prompt γ-ray is the measured radiation
Prompt γ -ray neutron activation analysis (PGNAA)
The measurements take place during irradiation.
If Delayed γ-ray is the measured radiation.
Delayed γ -ray neutron activation analysis (DGNAA)
The measurements take place after a certain decay period.
An experiment for deterimining the elemental composition of material by (PGNAA) using 239Pu-Be neutron source.
used reaction is
Inelastic scattering (n, n’ γ)
Aim of the work
Experimental work
An experiment setup for deterimining the elemental composition of material by (PGNAA)
We use a 239Pu-Be as source of continous neutron flux with energy around 4.2 Mev
To register gamma rays coming from interaction of neutrons with nuclei we use HPGe detector .
To protect the detectors from direct radiation of neutron source we use shielding of Pb/Bi of nearly 30 cm total length
Experimental work Three types of ore samples for analysis
Table 1. Content of different controlled elements in phosphate ore
1. Concentrate sample with high concentration of P2O5-38,95%
2. Tail sample with low concentration of P2O5 – 0,9%
3. X sample (mixture) with concentration of P2O5 between the value of first and second
Tails, mass
%
concentrate,
mass %
Controlled
element
0.90 38.98 P2O5
20.88 0.99 Al2O3
4.90 50.58 CaO
42.16 2.38 SiO2
8.02 0.68 Fe2O3
6.02 0.24 K2O
0.15 0.06 H2O
2.92 0.33 TiO2
10.26 0.50 Na2O
Experimental work
Back ground radiation curve was recorded without sample inside. Important step in work
with any gamma-spectroscopy instrument is to have well done channel-energy calibration.
In our case the calibration was performed by two methods:
1. by standard point sources (60Co & 137Cs)
2. by irradiation of metal samples.
60Co : 1173.2 and 1332.5 KeV
137Cs : 661.7 KeV
The channel-energy calibration curve
Results and discussion
• in the figure below is shown the comparison between gamma-spectra from three irradiated samples (concentrate – black , tails – red, X“mixture” – purple) and background –blue )
Part of gamma-ray energy
spectrum (2.0 - 2.5) MeV
Figure 1. Part of gamma-ray energy spectrum (2.0-2.5 MeV). Figure 2 Comparison of the energy resolutions of HPGe and
BGO detectors.
• In Figure 2 is shown the comparison between the measurements made with different types of detectors:
HPGe (with high resolution)
BGO (with high efficiency)
• Although BGO has a higher efficiency of gamma-ray detection, it has a moderate energy resolution.
• For example: if we compare Figure 1 with Figure 2 especially the interval between 2.20 and 2.25 MeV, .
in case of HPGe we can see that there are three lines from different sources (27Al, background and 31P).
In case of BGO (Figure 2, green and dark-blue lines) these gamma-lines, either from concentrate or from tails samples, can not be divided.
γ-line
energy,
keV
Attachment
(Concentrate
/Tails)
Isotope Table
energy, keV
751 Concentrate SE 31P 1266,13
766 Concentrate 44Ca 761,12
843 Mixture 27Al 56Fe
843,76
846,76
983 Tails 48Ti 983,54
1014 Tails 27Al 1014,52
1156 Concentrate 44Ca 1157,02
1238 Mixture,
Tails
56Fe 1238,27
1266 Concentrate 31P 1266,13
1369 Mixture 56Fe 39K
1360,21
1360,60
1635 Tails 23Na 1635,96
1811 Mixture,
Tails
56Fe 1810,76
2151 Concentrate 31P 2148,40
2213 Tails 27Al 2212,01
γ-line
energy,
keV
Attachment
(Concentrate
/Tails)
Isotope Table
energy,
keV
2237 Concentrate 31P
2233,60
2239,80
2275 Mixture,
Tails
56Fe
23Na
2273,20
2276,13
2263,39
2523 Mixture 56Fe 39K
2523,06
2522,40
2814-
2846
Tails 28Si 27Al 48Ti 39K
2838,29
2836,40
2819,08
2814,24
3132 Concentrate 31P 3134,30
3223 Concentrate SE 40Ca 3736,30
3732 Concentrate 40Ca 48Ti
3736,30
3738,35
7580 Mixture,
Tails
48Ti 7585,00
Some of the Identified Isotopes gamma-lines in the acquired spectra.
Conclusions
• An experimental setup for determining the elemental composition of materials by prompt gamma-ray neutron activation analysis (PGNAA) was commissioned and tested.
• The acquired spectra was processed and decoded successful.
Thank you for your attention