Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy
The values of relative cumulative yields of 12 products (⁸⁵mKr, ⁹¹mY, ⁹²Sr, 97Zr, ⁹⁹Mo, ¹⁰⁵Ru, ¹³³I, ¹³⁴I, ¹³⁵I, ¹³⁸Cs, ¹³⁹Ba, ¹⁴²La, ¹⁴³Ce) of the ²³⁹Pu photofission was measured at a maximum bremsstrahlung energy of 17.5 MeV (average excitation energy ~ 12.03 MeV). ²³⁹Pu photofission reaction was...
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nasplib_isofts_kiev_ua-123456789-1954592025-02-09T20:37:53Z Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy Вихід продуктів фотоподілу ²³⁹Pu при максимальній енергії гальмівного випромінювання 17,5 МеВ Выходы продуктов фотоделения ²³⁹Pu при максимальной энергии тормозного излучения 17,5 МэВ Parlag, O.O. Maslyuk, V.T. Oleynikov, E.V. Pylypchynets, I.V. Lengyel, A.I. Nuclear physics and elementary particles The values of relative cumulative yields of 12 products (⁸⁵mKr, ⁹¹mY, ⁹²Sr, 97Zr, ⁹⁹Mo, ¹⁰⁵Ru, ¹³³I, ¹³⁴I, ¹³⁵I, ¹³⁸Cs, ¹³⁹Ba, ¹⁴²La, ¹⁴³Ce) of the ²³⁹Pu photofission was measured at a maximum bremsstrahlung energy of 17.5 MeV (average excitation energy ~ 12.03 MeV). ²³⁹Pu photofission reaction was stimulated on the electron accelerator of the Institute of Electron Physics NAS of Ukraine – M-30 microtron to simulate the spectra of bremsstrahlung’s photons, secondary electrons, and photoneutrons that hit the ²³⁹Pu target, the GEANT4 code was used. The input of accompanying nuclear reactions to the yield of ²³⁹Pu photofission products for the given experimental parameters was also evaluating. The obtained experimental data of the yields of products ²³⁹Pu photofission were compared with the program codes GEF and Talys1.9.5 simulations. Значення 12-ти відносних кумулятивних виходів продуктів (⁸⁵mKr, ⁹¹mY, ⁹²Sr, 97Zr, ⁹⁹Mo, ¹⁰⁵Ru, ¹³³I, ¹³⁴I, ¹³⁵I, ¹³⁸Cs, ¹³⁹Ba, ¹⁴²La, ¹⁴³Ce) фотоподілу ²³⁹Pu були виміряні при максимальній енергії гальмівного випромінювання 17,5 МеВ (середня енергія збудження ~ 12,03 МеВ). Стимуляція реакції фотоподілу ²³⁹Pu проводилася на прискорювачі електронів Інституту електронної фізики НАН України – мікротроні М-30. Для моделювання спектрів гальмівних фотонів, вторинних електронів і фотонейтронів, що попадали на мішень ²³⁹Pu, використовувався код GEANT4. Було проведено оцінку внеску супутніх ядерних реакцій у виходи продуктів фотоподілу ²³⁹Pu при заданих параметрах експерименту. Отримані експериментальні дані по виходах продуктів фотоподілу ²³⁹Pu порівнювалися з результатами симуляції кодами GEF і Talys1.9.5 Значения 12-ти относительных кумулятивных выходов продуктов (⁸⁵mKr, ⁹¹mY, ⁹²Sr, 97Zr, ⁹⁹Mo, ¹⁰⁵Ru, ¹³³I, ¹³⁴I, ¹³⁵I, ¹³⁸Cs, ¹³⁹Ba, ¹⁴²La, ¹⁴³Ce) фотоделения ²³⁹Pu были измерены при максимальной энергии тормозного излучения 17,5 МэВ (средняя энергия возбуждения ~ 12,03 МэВ). Стимуляция реакции фотоделения ²³⁹Pu проводилась на ускорителе электронов Института электронной физики НАН Украины – микротроне М-30. Для моделирования спектров тормозных фотонов, вторичных электронов и фотонейтронов, попадающих на мишень ²³⁹Pu, использовался код GEANT4. Проведена оценка вклада сопутствующих ядерных реакций в выходы продуктов фотоделения ²³⁹Pu при заданных параметрах эксперимента. Полученные экспериментальные данные по выходам продуктов фотоделения ²³⁹Pu сравнивались с результатами симуляции кодами GEF и Talys1.9.5. The authors would like to express their gratitude to the microtron group (I.I. Hainish, H.F. Pitchenko, O.M. Turkhovskyi) for the smooth operation of the accelerator and I.M. Kushtan for the technical support of experimental research. 2021 Article Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy / O.O. Parlag, V.T. Maslyuk, E.V. Oleynikov, I.V. Pylypchynets, A.I. Lengyel // Problems of Atomic Science and Technology. — 2021. — № 6. — С. 8-12. — Бібліогр.: 18 назв. — англ. 1562-6016 PACS: 24.75.+1, 25.85.-w, 25.85. Ec, 25.85. Ca DOI: https://doi.org/10.46813/2021-136-008 https://nasplib.isofts.kiev.ua/handle/123456789/195459 en Вопросы атомной науки и техники application/pdf Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
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Nuclear physics and elementary particles Nuclear physics and elementary particles |
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Nuclear physics and elementary particles Nuclear physics and elementary particles Parlag, O.O. Maslyuk, V.T. Oleynikov, E.V. Pylypchynets, I.V. Lengyel, A.I. Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy Вопросы атомной науки и техники |
| description |
The values of relative cumulative yields of 12 products (⁸⁵mKr, ⁹¹mY, ⁹²Sr, 97Zr, ⁹⁹Mo, ¹⁰⁵Ru, ¹³³I, ¹³⁴I, ¹³⁵I, ¹³⁸Cs, ¹³⁹Ba, ¹⁴²La, ¹⁴³Ce) of the ²³⁹Pu photofission was measured at a maximum bremsstrahlung energy of 17.5 MeV (average excitation energy ~ 12.03 MeV). ²³⁹Pu photofission reaction was stimulated on the electron accelerator of the Institute of Electron Physics NAS of Ukraine – M-30 microtron to simulate the spectra of bremsstrahlung’s photons, secondary electrons, and photoneutrons that hit the ²³⁹Pu target, the GEANT4 code was used. The input of accompanying nuclear reactions to the yield of ²³⁹Pu photofission products for the given experimental parameters was also evaluating. The obtained experimental data of the yields of products ²³⁹Pu photofission were compared with the program codes GEF and Talys1.9.5 simulations. |
| format |
Article |
| author |
Parlag, O.O. Maslyuk, V.T. Oleynikov, E.V. Pylypchynets, I.V. Lengyel, A.I. |
| author_facet |
Parlag, O.O. Maslyuk, V.T. Oleynikov, E.V. Pylypchynets, I.V. Lengyel, A.I. |
| author_sort |
Parlag, O.O. |
| title |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy |
| title_short |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy |
| title_full |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy |
| title_fullStr |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy |
| title_full_unstemmed |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy |
| title_sort |
product yields for the photofission of ²³⁹pu with bremsstrahlung at 17.5 mev boundary energy |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2021 |
| topic_facet |
Nuclear physics and elementary particles |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/195459 |
| citation_txt |
Product yields for the photofission of ²³⁹Pu with bremsstrahlung at 17.5 MeV boundary energy / O.O. Parlag, V.T. Maslyuk, E.V. Oleynikov, I.V. Pylypchynets, A.I. Lengyel // Problems of Atomic Science and Technology. — 2021. — № 6. — С. 8-12. — Бібліогр.: 18 назв. — англ. |
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Вопросы атомной науки и техники |
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ISSN 1562-6016. ВАНТ. 2021. № 6(136) 8
https://doi.org/10.46813/2021-136-008
PRODUCT YIELDS FOR THE PHOTOFISSION OF
239
Pu
WITH BREMSTRAHLUNG AT 17.5 MeV BOUNDARY ENERGY
O.O. Parlag, V.T. Maslyuk, E.V. Oleynikov, I.V. Pylypchynets, A.I. Lengyel
Institute of Electron Physics, Uzhhorod, Ukraine
E-mail: eugene.oleinikov@gmail.com
The values of relative cumulative yields of 12 products (
85m
Kr,
91m
Y,
92
Sr,
97
Zr,
99
Mo,
105
Ru,
133
I,
134
I,
135
I,
138
Cs,
139
Ba,
142
La,
143
Ce) of the
239
Pu photofission was measured at a maximum bremsstrahlung energy of 17.5 MeV (av-
erage excitation energy ~ 12.03 MeV).
239
Pu photofission reaction was stimulated on the electron accelerator of the
Institute of Electron Physics NAS of Ukraine – M-30 microtron to simulate the spectra of bremsstrahlung’s photons,
secondary electrons, and photoneutrons that hit the
239
Pu target, the GEANT4 code was used. The input of accom-
panying nuclear reactions to the yield of
239
Pu photofission products for the given experimental parameters was also
evaluating. The obtained experimental data of the yields of products
239
Pu photofission were compared with the pro-
gram codes GEF and Talys1.9.5 simulations.
PACS: 24.75.+1, 25.85.-w, 25.85. Ec, 25.85. Ca
INTRODUCTION
Information on the yields of
239
Pu nuclear fission
products plays an important role in the development of
methods for transmutation of spent nuclear fuel (which
in large quantities contains products of (n,f)- and (γ,f)-
reactions) and non-destructive methods of isotope anal-
ysis of fissile nuclear materials. The above mentioned
directions require reliable experimental information on
the yields of
239
Pu photofission products, which is cur-
rently limited both in the range of studied fragments and
in the field of stimulation energies (γ,f)-reactions [1 - 5].
The aim of this work is to experimentally investigate
the yields of the fission products of the
239
Pu nucleus on
an electronic accelerator M-30 microtron at a maxi-
mum bremsstrahlung energy of 17.5 MeV and compare
the obtained data with the results of modeling by mod-
ern calculation codes (phenomenological fission mod-
els) “GEF 2021/1.1” [6] and “Talys 1.95” [7].
To implement this task, the following were per-
formed: modeling of the optimal scheme of the experi-
ment to stimulate the
239
Pu photofission reaction taking
into account the technical characteristics of the M-30
microtron and the parameters of the fission target using
the GEANT4 toolkit [8]; analysis of the contribution of
the outputs of related reactions to the outputs of the pho-
tofission products of
239
Pu; experimental studies of the
relative yields of
239
Pu photofission products by their
gamma radiation; and simulation of product outputs for
the fissible nucleus of
239
Pu* (E* 12.03 MeV) using
"GEF 2021/1.1" [6] and "Talys 1.95" codes [7].
1. MATERIALS AND METHODS
Determination of relative cumulative yields of
239
Pu
photofission products was performed by semiconductor
gamma-ray spectrometry [9 - 11]. The studied value
during measurements is the counting rate in peaks of
total absorption (or peak intensity) of gamma quanta
from individual fission products, which depends on its
activity, absolute measurement efficiency, self-
absorption corrections, and gamma line intensity.
1.1.
239
Pu FISSION TARGET
A target with plutonium isotopes:
239
Pu – 99% and
238
Pu – 1% was used for experimental studies. The ac-
tive layer of plutonium (disc diameter – 11 mm) was
applied to a stainless steel substrate disc with a diameter
of 24 mm and a thickness of 1 mm. The target was
manufactured at the V.G. Khlopin Radium Institute
(Saint Petersburg, Russia). The number of
239
Pu and
238
Pu nuclei was – 1.398xE16 and 1.121x10E7, respec-
tively, at the time of the experiment. The target was not
exposed to radiation before the experimental studies.
1.2. SIMULATION OF THE FISSION TARGET
ACTIVATION PROCESS
The GEANT410.7 computing code was used to sim-
ulate the spectra of bremsstrahlung photons, residual
electrons, and photoneutrons (depending on the energy
normalised per electron) which hit the target. The input
parameters used in the calculations almost completely
reproduced the geometric dimensions (design features)
of the electron output unit and the activation schemes of
fissile nuclei, which was implemented on an electron
accelerator – the M-30 microtron [12] (Fig. 1).
Fig. 1. Scheme of activation of
239
Pu target
on the microtron M-30:
1 output node of the microtron M-30; 2 window
of the output node (ellipse, thickness 50 μm);
3 photons converter (Ta, 100501 mm); 4 filter
B4C (D = 30 mm, thickness = 19 mm); 5 substrate
(stainless steel disc, diameter 24 mm, thickness 1 mm);
6
239
Pu layer; 7 Al collector of fission products
The simulation considered the geometric dimensions
of the original electron beam: the shape – an ellipse, the
dimensions of the semi-axes – 11 and 3 mm) and char-
acteristic of
239
Pu fissioning target. Calculations were
mailto:eugene.oleinikov@gmail.com
ISSN 1562-6016. ВАНТ. 2021. № 6(136) 9
performed for 10E9 electrons in the initial beam on two
computers with 6-core Intel(R) Core(TM) processors
i7-9750HCPU@2.60GHz and 36 GB and 16 GB RAM.
The influence of the elements of the activation cir-
cuit (converter, filter [13], stainless steel substrate) on
the final shape of the spectra of photons, residual elec-
trons and photoneutrons, which hit on the fissile
239
Pu
layer, was established (Fig. 2).
0 5 10 15
10-5
10-4
10-3
10-2
P
h
o
to
n
s
/
e
Ephotons, MeV
- Ta
- Ta+B4C
- Ta+B4C+Steel
a
0 5 10 15 20
10-9
10-7
10-5
10-3 b
E
le
c
tr
o
n
s
/
e
Ee, MeV
- Ta
- Ta+B4C
- Ta+B4C+Steel
0 1 2 3 4 5
2.0x10-8
4.0x10-8
6.0x10-8
c
N
e
u
tr
o
n
s
/
e
En, MeV
- Ta
- Ta+B4C
- Ta+B4C+Steel
Fig. 2. Spectra of photons (a), residual electrons (b) and
photoneutrons (c) on the fissile layer of
239
Pu: square –
Ta-converter – fissile layer; circle – Ta-converter +
B4C filter – fissile layer; triangle – Ta-converter + B4C
filter + stainless steel substrate – fissile layer
As a result of the simulation, the total number of
photons, residual electrons, and photoneutrons normal-
ised per electron hitting a fission target was calculated:
0.12913 photons (with an energy > 6 MeV, involved in
stimulating the photofission reaction – 0.01749);
– 0.01485 electrons (with an energy > 6 MeV
– 0.00571) and ~ 6.1E-7 neutrons.
Residual electrons that fell on the fission assembly
did not affect the results of the experiment.
The obtained results were used to estimate the con-
tribution of the outputs of the concomitant (accompany-
ing) nuclear reactions (
239
Pu(γ,n)
238
Pu →
238
Pu(γ,f);
238
Pu(n,f) and
239
Pu(n,f) to the outputs of the photofis-
sion products. The values of the cross sections of photo-
nuclear ((γ,n)-, (γ,f)-) and neutron ((n,f)- reactions from
the ENDF database) [14] (Fig. 3), were used in the cal-
culations (Fig. 4). The calculations of the number of the
nuclei
238
Pu, which were formed along the reaction
channel
239
Pu(γ,n)
238
Pu during the irradiation time
(0…4 hours) and the dependences of the number of the
photofission and neutron fission acts of the nuclei
238
Pu
and
239
Pu, on the irradiation time (0…4 hours) are rep-
resented in Fig. 4.
2 4 6 8 10 12 14 16 18 20
0.0
0.2
0.4
0.6
s
ig
m
a
,
B
Ephoton, MeV
239Pu(g,f)
239Pu(g,n)238Pu
238Pu(g,f)
0.1 1 10
0.1
1
10
S
ig
m
a
,
b
En, MeV
ENDF/B-VIII.0
239Pu(n,f)
238Pu(n,f)
Fig. 3. Cross sections of photonuclear (up)
and neutron reactions (down) [14]
0 1 2 3 4
10-35
10-29
10-23
10-17
10-11
10-5
Y
ie
ld
/
e
Tirr, h
- 239Pu(g,n)238Pu
- 239Pu(g,f)
- 238Pu(g,f)
- 239Pu(n,f)
- 238Pu(n,f)
Fig. 4. The dependence of the number of nuclei formed
from possible reaction channels, and the reaction rate
from the activation time (0…4 h) upon irradiation
of
239
Pu by bremsstrahlung with an energy of 17.5 MeV
a
b
c
ISSN 1562-6016. ВАНТ. 2021. № 6(136) 10
The analysis indicates the lack of influence of the
yields of the products of concomitant reactions on the
accuracy of the final results.
The results of the calculations allowed to optimize
the scheme of stimulation of the
239
Pu(γ,f) reaction on
the M-30 microtron.
1.3. STIMULATION OF THE
239
Pu
PHOTOFISSION REACTION
To accumulate photofission products during activa-
tion, 0.2 mm thick aluminum foil collectors were used,
which were installed close to the
239
Pu layer.
Irradiation of a fissible assembly (which consisted of
plutonium fissioning target and collector layer) were
performed on an electron accelerator of the Institute of
Electron Physics of the National Academy of Sciences
of Ukraine – an M-30 microtron (electron energy
E=17.5 MeV, average beam current ~ 4 μA) (see Fig. 1).
The instability of the electron energy during target irra-
diation did not exceed 0.04 MeV [12].
To generate bremsstrahlung, a tantalum converter
was used (thickness – 1 mm), located at a distance of
22 mm from the output window (Ta, thickness – 50 mi-
crons) of the electron output unit. The fission assembly
was installed perpendicular to the beam axis at a dis-
tance of 75 mm from the Ta converter. The filter of re-
sidual electrons and photoneutrons (B4C) was installed
close to the Ta-converter perpendicular to the axis of the
beam [13]. The irradiation time of the fission assembly
were – 3.5 and 3.75 hours. The choice of time parame-
ters (irradiation, cooling, and measurement times) was
made considering the half-lives of the studied photofis-
sion products and their precursors (the so-called “par-
ent” products) along the isobaric chain.
1.4. GAMMA-RAY SPECTROMETRIC STUDIES
OF
239
Pu PHOTOFISSION PRODUCTS
At the end of the accumulation of fragments, alumi-
num collectors measured their gamma activity for from
0.25 to 70 hours after the end of irradiation. The dura-
tion of individual measurements varied from 0.5 to
3 hours. For the research, spectrometric complexes
based on semiconductor detectors were used: HPGe
(Ortec) and Ge (Li), the volumes of which were 150 and
100 cm
3
with an energy resolution of ~ 2.45 and
~ 3.5 keV for the line
60
Co (1.332.5 keV) [15, 16].
When studying the relative cumulative yields of fission
products, the final error of the obtained results is pri-
marily affected by the error value of the measured ener-
gy efficiency of the detector.
The energy dependence of the peak efficiency of
gamma-ray quantum registration was determined using
a set of standard certified point sources
22
Na,
57
Co,
60
Co,
109
Cd,
133
Ba,
137
Cs,
151
Eu,
241
Am (produced by
D.I. Mendeleev Institute for Metrology, Saint Peters-
burg, Russia). The value of the statistical measurement
error during the calibration procedure did not exceed
4%.
Gamma-ray spectra from photofission products were
measured in real time. The dead time of the spectrome-
ter did not exceed 5…8% during all measurements.
During the measurements, the drift of the energy scale,
resolution and recording efficiency of the spectrometric
complex were constantly monitored using point stand-
ard gamma-active source
60
Co. The drift of these pa-
rameters did not exceed 1%. Spectroscopic information
was processed using the Winspectrum software package
[17]. Fission fragments were identified by the energies
of their characteristic gamma lines, considering their
half-lives and measurement, accumulation, and cooling
times. Additionally, the half-lives of their predecessors
along isobaric chains were considered. The values of
nuclear spectroscopic data of the identified fission
products (energies and intensities of gamma lines, half-
lives of the formed products and their precursors along
the isobaric chain) were taken for calculations from the
“Decay Radiation database” [18].
RESULTS AND DISCUSSION
During the experiment, we measured the peak inten-
sity of gamma lines belonging to the following products
of the
239
Pu nuclear photofission:
85m
Kr (151.2),
91m
Y
(555.6),
92
Sr (1383.9),
97
Zr (743.4),
99
Mo (739.5),
105
Ru
(724.3),
133
I (529.9),
134
I (847.0; 884.1),
135
I (1260.4),
138
Cs (1435.8),
139
Ba (165.9),
142
La (641.3),
143
Ce
(293.3). The energies of gamma lines are presented in
parentheses (in keV). The statistical error of measure-
ments of the peak intensity of gamma product lines used
in the analysis did not exceed 5% for the entire time
interval of measurements. Cumulative yields were de-
termined relative to the yields of the
97
Zr reference
product (4.63% [1]). The total error of relative cumula-
tive yields was estimated considering statistical errors of
peak intensity of gamma product lines, analysis of time
dependencies, spread of values averaged over individual
measurements, as well as errors of interpolated efficien-
cy values and nuclear physical constants (energy and
intensity of gamma lines, half-lives of products). The
total error in determining the relative cumulative yields
of fission fragments did not exceed 10%.
Due to the small size of the plutonium sample, a lim-
ited number of fission products were measured.
Experimental values of yields of
239
Pu photofission
products at a maximum bremsstrahlung photon energy
of 17.5 MeV are shown in Fig. 5 by black circle.
Squares and up triangles represent yields of fission
products at a maximum bremsstrahlung photon energy
of 28 and 30 MeV [1, 2]. Rombes and down triangles –
at 11 and 13 MeV with monoenergetic photons [4, 5].
At close excitation energies, our data agree with the
existing experimental data.
Fig. 5 also show the yields of fission products for a
239
Pu* fission nucleus at an excitation energy of
~ 12.03 MeV, calculated by the GEF code [6] (solid
curve) and Talys 1.95 code [7] (dashed line). The ob-
tained theoretical output values calculated using the
GEF 2020/1.1 code adequately describe the mass distri-
bution of
239
Pu photofission products. Talys 1.95 codes
describe in general terms the mass distribution of
239
Pu
photofission products only.
ISSN 1562-6016. ВАНТ. 2021. № 6(136) 11
80 100 120 140 160
0
2
4
6
8
10
- 17.5 MeV
- 28 Mev [1]
- 30 Mev [2]
- 11 MeV [4]
- 13 MeV [5]
- GEF [6]
- Talys [7]
Y
ie
ld
s
,
%
Mass, a.m.u.
Fig. 5. Yields of
239
Pu photofission products
CONCLUSIONS
Results of simulation the characteristics of brems-
strahlung radiation beam and its components (relation of
photons, residual electrons, and photoneutrons which
hit the target for M-30 microtron (taking into account
the constructive features of its electrons output node and
the characteristics of the fissile target), with help the
Geant 4 toolkit, allowed to develop an optimal scheme
for stimulating the reaction of the
239
Pu photofission,
which ensures the lack of exposure to the yields of re-
lated reactions to the precision of the final results.
The cumulative yields of 14
239
Pu photofission
products were determined by semiconductor gamma
spectroscopy at the maximum bremsstrahlung photon
energy of 17.5 MeV (E* ~ 12.03 MeV). The simulations
performed using the GEF and Talys1.95 codes describe
and predict of mass distributions for a fissile
239
Pu* nu-
cleus at an average excitation energy of ~ 12.03 MeV.
ACKNOWLEDGEMENTS
The authors would like to express their gratitude to
the microtron group (I.I. Hainish, H.F. Pitchenko,
O.M. Turkhovskyi) for the smooth operation of the ac-
celerator and I.M. Kushtan for the technical support of
experimental research.
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Article received 11.10.2021
ВЫХОДЫ ПРОДУКТОВ ФОТОДЕЛЕНИЯ
239
Pu ПРИ МАКСИМАЛЬНОЙ ЭНЕРГИИ
ТОРМОЗНОГО ИЗЛУЧЕНИЯ 17,5 МэВ
О.А. Парлаг, В.Т. Маслюк, Е.В. Олейников, И.В. Пилипчинец, А.И. Лендел
Значения 12-ти относительных кумулятивных выходов продуктов (
85m
Kr,
91m
Y,
92
Sr,
97
Zr,
99
Mo,
105
Ru,
133
I,
134
I,
135
I,
138
Cs,
139
Ba,
142
La,
143
Ce) фотоделения
239
Pu были измерены при максимальной энергии тормозного
излучения 17,5 МэВ (средняя энергия возбуждения ~ 12,03 МэВ). Стимуляция реакции фотоделения
239
Pu
проводилась на ускорителе электронов Института электронной физики НАН Украины – микротроне М-30.
Для моделирования спектров тормозных фотонов, вторичных электронов и фотонейтронов, попадающих на
мишень
239
Pu, использовался код GEANT4. Проведена оценка вклада сопутствующих ядерных реакций в
выходы продуктов фотоделения
239
Pu при заданных параметрах эксперимента. Полученные эксперимен-
тальные данные по выходам продуктов фотоделения
239
Pu сравнивались с результатами симуляции кодами
GEF и Talys1.9.5.
ВИХОДИ ПРОДУКТІВ ФОТОПОДІЛУ
239
Pu ПРИ МАКСИМАЛЬНІЙ ЕНЕРГІЇ
ГАЛЬМІВНОГО ВИПРОМІНЮВАННЯ 17,5 МeВ
О.О. Парлаг, В.Т. Маслюк, Є.В. Олейніков, І.В. Пилипчинець, О.І. Лендел
Значення 12-ти відносних кумулятивних виходів продуктів (
85m
Kr,
91m
Y,
92
Sr,
97
Zr,
99
Mo,
105
Ru,
133
I,
134
I,
135
I,
138
Cs,
139
Ba,
142
La,
143
Ce) фотоподілу
239
Pu були виміряні при максимальній енергії гальмівного випромі-
нювання 17,5 МеВ (середня енергія збудження ~ 12,03 МеВ). Стимуляція реакції фотоподілу
239
Pu проводи-
лася на прискорювачі електронів Інституту електронної фізики НАН України – мікротроні М-30. Для моде-
лювання спектрів гальмівних фотонів, вторинних електронів і фотонейтронів, що попадали на мішень
239
Pu,
використовувався код GEANT4. Було проведено оцінку внеску супутніх ядерних реакцій у виходи продуктів
фотоподілу
239
Pu при заданих параметрах експерименту. Отримані експериментальні дані по виходах проду-
ктів фотоподілу
239
Pu порівнювалися з результатами симуляції кодами GEF і Talys1.9.5.
https://www-nds.iaea.org/exfor/endf.htm
https://www-nds.iaea.org/exfor/endf.htm
https://www.nndc.bnl.gov/nudat2/indx_dec.jsp
|