Pepan Letters
Annual Reports
To Authors

Preprints and Communications

Here you can find JINR preprints and communications in pdf format starting from 1999.
File size is given in bytes in round brackets.

Subject Categories for JINR Publications Archive (1999 - 2020)

P13-2021-30 (3.512.569)
Pepelyshev Yu. N., Sumkhuu D.
Optimization of Automatic Power Control System of the IBR-2M Pulsed Reactor in the Presence of Instability

The paper presents the main results of computational and experimental optimization of the automatic power control system (AR) of the IBR-2M pulsed reactor in the presence of a high level of oscillatory instability. Optimization of the parameters of the AR made it possible to significantly reduce the influence of random and deterministic oscillations of reactivity on the noise of the pulse energy, as well as to sharply reduce the manifestation of the oscillatory instability of the reactor. As a result, the safety and reliability of operation of the reactor has increased substantially.

P13-2021-29 (4.037.416)
Pepelyshev Yu.N., Tsogtsaikhan Ts.
The Dynamics of Oscillation Instability of the IBR-2M Reactor. The Noise Analysis

The results of the study on noise dynamics and self-oscillations of the pulse energy in the IBR-2M for period from 2012 at the power of 2 MW until the middle of 2021 are presented. It is shown that with an increase in fuel burnup, the power spectral density of the pulse energy noise becomes more complicated and the amplitude of self-oscillations grows. Based on the data obtained, a strategy was developed to suppress the oscillatory instability of the IBR-2M, up to the life of the reactor in 2036. The need to continue research on the noise dynamics and oscillatory instability of the IBR-2M reactor was shown

P16-2021-25 (2.063.403)
Mokrov Yu. V., Morozova S. V., Schegolev V. Yu.
Determination of Correction Factors for Correction of the Individual Albedo Neutron Dosimeter DVGN-01 Readings in the Field of the DC-280 Accelerator

The paper presents the results of determining the correction coefficients for individual albedo neutron dosimeters DVGN-01 of the AKIDK-301 complex for correcting their readings when used by personnel in the field of the DC-280 accelerator. The correction coefficients have been determined using a spherical albedo system under irradiation at four points: in the accelerator hall near the radiation monitor and in front of the shield door from the accelerator hall (room 110) and in the beam output cabin (room 115). The obtained values of the coefficients are in good agreement with the coefficients obtained earlier on the MC-400 and used in the individual dosimetric control of the personnel of the FLNR.

P3-2021-22 (474.392)
Frank A. I., Kulin G. V., Rebrova N. V., Zakharov M. A.
On the Possibility of Creating a UCN Source on a Periodic Pulsed Reactor

The possibility of creating a UCN source on a periodic pulsed reactor is considered. It is shown that the implementation of the principle of time focusing, based on nonstationary neutron diffraction, and the idea of pulse filling of the trap for UCN allows us to create a sufficiently intense source of UCN on a pulsed reactor of a moderate power.

P4-2021-15 (341.197)
Efimov A. D., Izosimov I. N.
Systematic of the Yrast-Bands in the Region of Heavy and Superheavy Even-Even Nuclei

By using the extrapolation method, the estimations of yrast-band level energies for heavy and superheavy nuclei were obtained. For getting these estimations, the information about the properties of the neighboring nuclei was exploited. Such a method seems reasonable because for more collective states in the considered region of nuclei the yrast-band level energies varvary smoothly and slightly. The obtained results are very significant both for the experiment planning and for the analysis of the experimental data on the observation and study of the β- and γ-decays of high-spin isomers in the region of heavy and superheavy nuclei.

P13-2021-11 (1.934.096)
Pepelyshev Yu. N., Sumkhuu D.
The Cycle Changing of Dynamics of the IBR-2M Pulsed Reactor

It is shown that in the IBR-2M reactor by the end of the reactor cycle, changes in dynamics are observed associated with a strong weakening of the fast power feedback (PFB), as a result of which the reactor becomes oscillatory unstable. When the reactor is shut down, negative changes in dynamics disappear and the stability of the reactor is restored. Thus, the reactor undergoes cyclic changes in the oscillatory instability. The correlation between a fast PFB and a slow PFB is experimentally observed, which makes it possible to almost completely eliminate the cyclic component of instability by changing the control mode of rods of the control system.

P6-2021-6 (292.654)
Mukhin R. S. et al.
Reconstruction of Spontaneous Fission Neutron Multiplicity Distribution Spectra by the Statistical Regularization Method

We propose a technique for reconstructing the multiplicity distribution of spontaneous fission neutrons using the Tikhonov regularization method. The results obtained for 252No, 244Fm, 246Fm, and 248Cm are compared with previously reconstructed distributions. The multiplicity distributions of spontaneous fission neutrons of 250No, 256Rf, and 254Rf were reconstructed for the first time. For each spectrum, the mean number of neutrons per decay and the dispersion of the distribution were obtained.

D18-2021-5 (301.267)
Eganova I. A. et al.
Ad Disputandum: The Most Topical Scientific Ideas That Were Highlighted in Time of Coronavirus Pandemic

It is indisputable that without a proper worldview, without a proper understanding of physical reality, science is unable to provide a sustainable future on our planet. It is expedient and very timely for the authors to submit judgment presented in this article of the deep essence of the main results, which form the foundations of the scientific understanding of objective reality. Talk is about a really adequate model of spacetime, about a physical mechanism of global (terrestrial and cosmic) interactions and about the planet Earth as superorganism a representative of a special form of cosmic life.

P4-2021-4 (460.524)
Efimov A. D., Izosimov I. N.
High-Spin States of Yrast-Bands Even Isotopes Pu, Cm, Fm, No

In some isotopes of Pu, Cm, Fm, No, the yrast-band state energies are experimentally known up to the spin 32+, like this holds in 248Cm. What is unique is that all the states of these superlong bands remain purely collective. Collectivity of the bands manifests itself in the fact that the band state energies are reproduced with a high degree of accuracy within the framework of the phenomenology of the IBM1. The uncertainty of the model parameters is reduced under condition that the depth of the deformation energy obtained on the basis of realistic interactions was equal to the deformation energy depth in the internal state, calculated with the found parameters of the IBM1 Hamiltonian.

2021-3 (5.317.371)
Brief Review of Topmost Scientific Results Obtained in 2020 at the Joint Institute for Nuclear Research