=Paper=
{{Paper
|id=Vol-2267/195-199-paper-36
|storemode=property
|title=NRV web knowledge base: scientific and educational applications
|pdfUrl=https://ceur-ws.org/Vol-2267/195-199-paper-36.pdf
|volume=Vol-2267
|authors=Alexander V. Karpov,Andrey S. Denikin,Viacheslav V. Samarin,Mikhail A. Naumenko, Alexander P. Alekseev,Vladimir A. Rachkov,Viacheslav V. Saiko,Leslie М. Lekala,Bahati Mukeru.
}}
==NRV web knowledge base: scientific and educational applications==
https://ceur-ws.org/Vol-2267/195-199-paper-36.pdf
Proceedings of the VIII International Conference "Distributed Computing and Grid-technologies in Science and
Education" (GRID 2018), Dubna, Moscow region, Russia, September 10 - 14, 2018
NRV WEB KNOWLEDGE BASE: SCIENTIFIC AND
EDUCATIONAL APPLICATIONS
A. V. Karpov 1, 2, a, A. S. Denikin 1, 2, V. V. Samarin 1, 2, M. A. Naumenko 1,
A. P. Alekseev 3, V. A. Rachkov 1, 2, V. V. Saiko 1, 2, L. M. Lekala 4,
B. Mukeru 4
1
Joint Institute for Nuclear Research, 6 Joliot-Curie st., Dubna, Moscow reg., 141980, Russia
2
Dubna State University, 19 Universitetskaya st., Dubna, Moscow reg., 141982, Russia
3
Chuvash State University, 15 Moskovskiy av., Cheboksary, Chuvash Republic, 428015, Russia
4
University of South Africa, P.O. Box 392, Pretoria, 0003, South Africa
E-mail: a karpov@jinr.ru
The NRV web knowledge base on low-energy nuclear physics has been created in the Joint Institute
for Nuclear Research. This knowledge base working through the Internet integrates a large amount of
digitized experimental data on the properties of nuclei and nuclear reaction cross sections with a wide
range of computational programs for modeling of nuclear properties and various processes of nuclear
dynamics which run directly in the browser of a remote user. Today, the NRV knowledge base is both
a powerful tool for nuclear physics research and an educational resource. The system is widely used,
as evidenced by the large number of user queries to its resources and the number of references to the
knowledge base in the articles published in scientific journals. The practical usage of the NRV
knowledge base for both scientific and educational applications is demonstrated.
Keywords: web knowledge base, low-energy nuclear physics, nuclear data, nuclear reactions
© 2018 Alexander V. Karpov, Andrey S. Denikin, Viacheslav V. Samarin, Mikhail A. Naumenko,
Alexander P. Alekseev, Vladimir A. Rachkov, Viacheslav V. Saiko, Leslie М. Lekala, Bahati Mukeru.
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Proceedings of the VIII International Conference "Distributed Computing and Grid-technologies in Science and
Education" (GRID 2018), Dubna, Moscow region, Russia, September 10 - 14, 2018
1. Introduction
The NRV web knowledge base on low-energy nuclear physics [1-3] has been created in the
Joint Institute for Nuclear Research under the leadership of Prof. V.I. Zagrebaev. This knowledge base
working through the Internet integrates a large amount of digitized experimental data on the properties
of nuclei and nuclear reaction cross sections with a wide range of computational programs for
modeling of nuclear properties and various processes of nuclear dynamics which run directly in the
browser of a remote user. Today, the NRV knowledge base is both a powerful tool for nuclear physics
research and an educational resource.
The practical usage of the NRV knowledge base for scientific purposes is demonstrated in
detail on the example of the analysis of synthesis of heavy and superheavy nuclei in fusion reactions.
The practical usage of the NRV knowledge base for educational purposes illustrated on the example of
the analysis of elastic scattering.
2. Analysis of formation of neutron-enriched heavy and superheavy nuclei
in fusion reactions
The production and study of heavy and superheavy elements is one of the most important
problems in modern nuclear physics. Figure 1 shows the upper part of the map of nuclei. It can be seen
that only neutron-deficient nuclei were synthesized for elements heavier than fermium, while the
region of heavy neutron-enriched nuclei remains unstudied. This region is highly important for
astrophysical research, in particular, for understanding the possibility of formation of superheavy
elements in the astrophysical r-process.
Figure 1. Upper part of the map of nuclei
To reach this region, one can use fusion reactions with more neutron-rich nuclei. For example,
in Ref [4] it was proposed to synthesize neutron-enriched isotopes of nuclei with Z of 102–108 using
fusion reactions of stable (22Ne) and radioactive (23Ne, 20O) neutron-rich projectiles with actinide
targets 248Cm, 249Bk, and 249Cf, followed by the evaporation of charged particles (proton or α particle)
and neutrons from the compound nucleus. In Ref [4], predictions for the above-mentioned fusion cross
sections were made using the NRV web knowledge base on low-energy nuclear physics. Figure 2
shows the results of calculation of cross sections for formation of new isotopes of superheavy
elements in the xn, pxn, and αxn evaporation channels of fusion reactions.
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Proceedings of the VIII International Conference "Distributed Computing and Grid-technologies in Science and
Education" (GRID 2018), Dubna, Moscow region, Russia, September 10 - 14, 2018
Figure 2. Results of calculation of cross sections for formation of new isotopes of superheavy elements in the xn,
pxn, and αxn evaporation channels of fusion reactions performed in Ref [4] using the NRV web knowledge base
The use of the NRV web knowledge base for the analysis of the fusion reaction 16O + 150Nd
and calculation of evaporation residues cross sections is illustrated in Figure 3. The left-hand side
window shows the web dialog for choosing the parameters of the channel coupling model [5] applied
to calculation of the fusion cross section. It should be mentioned that experimental data on nuclear
properties available in the knowledge base the can be used to determine the model parameters. This
possibility significantly simplifies the use of many theoretical models. In addition, the knowledge base
also contains detailed descriptions of the models and parameters used. The right-hand side window
shows the results of calculation of evaporation residues. The obtained results may be saved in the text
(tabular) or in the graphical formats on the user’s computer.
Figure 3. Use of the NRV web knowledge base for the analysis of the fusion reaction 16O + 150Nd
In addition to the possibility of performing calculations of fusion and fusion-evaporation cross
sections, the NRV web knowledge base contains more than 1600 experimental fusion excitation
functions and more than 300 experimental evaporation residues cross sections including references to
original papers, which makes it a unique source of information on the current state of research in this
field. The experimental databases are constantly updated.
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Proceedings of the VIII International Conference "Distributed Computing and Grid-technologies in Science and
Education" (GRID 2018), Dubna, Moscow region, Russia, September 10 - 14, 2018
3. Study of elastic scattering of nuclei in optical model
Elastic scattering is one the simplest processes among all channels of nucleus-nucleus
collisions, therefore the corresponding section of the NRV web knowledge base is widely used for
educational purposes. Students may study the application of both classical mechanics and quantum
mechanics to the scattering problem as well as the quasiclassical limit in the transition from light
nuclei to heavy nuclei.
Figure 4 shows the web dialog for choosing the parameters of the optical model and starting
calculation for the reaction 6Li + 28Si. The results of calculations are shown in Figure 5. It can be seen
that with the chosen parameters the optical model code describes the experimental elastic scattering
cross section rather well. The NRV web knowledge base contains more than 1200 experimental elastic
scattering cross sections.
Figure 4. Web dialog for choosing the parameters of the optical model and starting calculation
Figure 5. Results of optical model calculation
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Proceedings of the VIII International Conference "Distributed Computing and Grid-technologies in Science and
Education" (GRID 2018), Dubna, Moscow region, Russia, September 10 - 14, 2018
One of the great advantages of the code is the possibility of automatic fitting of the model
parameters, which significantly simplifies its use, especially for unexperienced users.
Due to the wide use of the optical model by Russian-speaking students, tutorial in Russian on
the optical model is also available at http://nrv.jinr.ru/nrv/OM-Tutorial.pdf.
For scientific purposes, the optical model of the NRV web knowledge base was successfully
used, e.g., in Ref. [6] for studying total cross sections for reactions 4,6He + 28Si and 6,7,9Li + 28Si.
4. Conclusions
In this work, practical usage of the NRV web knowledge base was demonstrated on the
example of the analysis of synthesis of heavy and superheavy in fusion reactions and example of the
analysis of elastic scattering.
The web knowledge base is an efficient tool for acquisition and development of skills of work
with modern theoretical approaches to the description of properties of individual nuclides, modeling of
the dynamics of nuclear collisions, as well as the skills of work with experimental data and their
systematization. The development of manuals and guidelines for the implementation of practical work
may effectively introduce the NRV web knowledge base in the educational process of any university
preparing students in the field of nuclear physics.
At present, the NRV web knowledge base is widely used for educational purposes, e.g., by
students of Dubna State University (Dubna, Russia), Moscow State University (Moscow, Russia),
National Research Nuclear University MEPhI (Moscow, Russia), University of South Africa (South
Africa), Karadeniz Technical University (Trabzon, Turkey), L.N. Gumilyov Eurasian National
University (Astana, Kazakhstan), and Nazarbayev University (Astana, Kazakhstan). It is also used by
students visiting Joint Institute for Nuclear Research for various student practice.
The further development of the NRV knowledge base is planned in the following directions:
(1) filling and updating of the existing nuclear databases as well as adding new ones;
(2) implementation of new physical models as well as extending the possibilities of the existing ones;
(3) modernization of the user interface; (4) preparing new tutorials in Russian and in English.
Acknowledgements
The work was supported by RSA-JINR (Dubna) Cooperation program.
References
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Samarin V.V., Saiko V.V. NRV Web Knowledge Base on Low-Energy Nuclear Physics.
http://nrv.jinr.ru/.
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Nuclei in Fusion Reactions // Phys. Part. Nucl. Lett. 2018. Vol. 15. P. 247–256.
[5] Samarin V.V., Zagrebaev V.I. Channel Coupling Analysis of Initial Reaction Stage in Synthesis of
Super-Heavy Nuclei // Nucl. Phys. A. 2004. Vol. 734. P. E9–E12.
[6] Penionzhkevich Yu. E., Sobolev Yu. G., Samarin V. V., Naumenko M. A. Peculiarities in Total
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