PREPRINTS

Preprint IBRAE-2012-06

Blokhin P.A., Mitenkova E.F. 

GrayS program (Gamma-ray Source) for γ-source generation for given mixture of radionuclides, is presented. The calculations results of γ-sources and activity of spent fuel for BN and VVER-1000 reactors are discussed. The intercomparison of γ-radiation for isotopes (W188, Np237, Pu238, Pr150, Eu156, Ra228, Ru105) are based on BROND-3/DD, ENDF/B-VII.0 and JEFF-3.1.1.

Bibliographical reference 

Blokhin, P.A. Specification of GrayS program for γ-source generation / P.A. Blokhin, E.F. Mitenkova — (Preprint / Nuclear Safety Institute RAS, IBRAE-2012-06). — Moscow : NSI RAS, 2012. — 28 p. — Bibliogr.: 15 items.

Preprint IBRAE-2012-05

Mitenkova  E.F., Solovjevа E.V. 

The RECYCL programming module from CFC_BN is intended for generation of calculated files used when scenario realizing of recycling fuel cycles. This work is realized as a part of the specialized programming complex CFC_BN, intended for fuel cycle simulation using MCNP-MONTEBURNS-ORIGEN core calculations. RECYCL description is represented in the paper

Bibliographical reference

Mitenkova E. RECYCL programming module for core simulation with fuel recycling / E.F. Mitenkova, E.V. Solovjeva — (Preprint / Nuclear Safety Institute RAS, November 2012, № IBRAE-2012-05). — Moscow : NSI RAS, 2012. — 18 p. — Bibliogr.: 11 items.

Preprint IBRAE-2012-04

Brednikhin S.A., Lezhnin S.I., Frolov S.A., Yurov D.M.

The paper describes the structure of NMC, a new generation Monte-Carlo particle transport code. The code is capable to solve a wide range of standard problems such as computation for reactor unit flux. Besides of this it can easily be refined to solve highly specialized tasks with most effective method. The paper presents the results of: code validation with computation of effective multiplication factor and neutron flux energy density function of benchmark experiments from International Handbook Of Evaluated Criticality Safety Benchmark Experiments; neutron-physical characteristics study of the subcritical nuclear assembly, designed to operate in the hybrid fission-fusion system with a neutron source based on plasma gas-dynamic trap (GDT).
Based on the obtained results it is concluded about the possibility of using the code for scientific search purposes for modeling of the neutral particles transport processes as well as for testing new algorithms for statistical modeling.

Bibliographical reference 

Brednikhin S.A., Lezhnin S.I., Frolov S.A., Yurov D.M. NMC CODE FOR STATISTICAL MODELING OF NEUTRON TRANSFER IN FISSILE MEDIA. — Preprint / Nuclear Safety Institute RAS IBRAE-2012-04. — Moscow : NSI RAS, 2012. — 24 p. — Refs.: 10 items.

Preprint IBRAE-2012-03

Melikhova E.M., Barkhudarova I.E.

Evaluation of current demographic situation and long-term trends of population development in radiation contaminated territories requires proper choice of reference regions and consistent accounting for statistical errors. Review of last decade publications considering quality of vital statistics in Russia at national and regional levels provided us with basic information for estimation of statistical errors of different demographic indices in Central Russia regions. The errors were not omissible, and the Bryansk Region was taken as an example to get low-bound-estimates of the errors, validate reference regions selection and demonstrate the effect of consistent accounting for statistical errors in comparative analysis. It was shown that after Chernobyl accident demographic development of the Bryansk Region followed the general tendencies of the Central District (excluding the capital city). Against prevailing opinion, the Bryansk Region has never been among outsiders. It has neither progress, no regress in comparison with the typical middling regions of the Central District. A number of publications were analyzed to demonstrate typical mistakes in methods that lead to wrong interpretations of the Bryansk Region demographic situation.

Bibliographical reference 

Melikhova E.M., Barkhudarova I.E. Methodical Aspects of Evaluating Longterm Population Development in Contaminated TerrItories (by Example of the Bryansk Region). Preprint № IBRAE-2012-03. Moscow: Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 2012. 33 p.

Preprint IBRAE-2012-01

Bibliographical reference 

Arutyunyan R.V., et al. LOCALIZATION OF THE CHERNOBYL ACCIDENT MEASURES. — Preprint / Nuclear Safety Institute RAS IBRAE-2012-01. — Moscow : NSI RAS, 2012. — 54 p. — Refs.: 49 items.

Preprint IBRAE-2011-08

The transport point-wise nuclear data libraries are generated on the basis of latest versions of evaluated neutron data files ENDF/B-VII.0, JEFF-3.1.1 and JENDL-4.0 when using the software system NJOY-99. These libraries can be used in MCNP5 calculations. When ENDF processing, the features in the evaluated nuclear data representation were fixed and the appropriate corrections were produced for them. The libraries were prepared at the temperature T = 300 K including the additional information for self-shielding factors of the neutron cross sections using in Monte Carlo calculations with point-wise libraries.

Bibliographical reference 

Blokhin D.A. . Generation of pointwise nuclear data library on the basis of ENDF/B-VII.0, JEFF-3.1.1, JENDL-4.0. /D.A. Blokhin, E.F. Mitenkova, A.I. Blokhin — (Preprint / Nuclear Safety Institute RAS, December 2011, № IBRAE-2011-08). — Moscow : NSI RAS, 2011. — 58 p. — Bibliogr.: 8 items.

Preprint IBRAE-2011-07

The results of assessment of source term in the accident at Fukushima-1 NPP and modeling of the radiation situation in Japan territory using detailed three-dimensional fields of meteorological data are presented. It is shown that the wind, temperature and precipitation fields found from the WRF-ARW model with resolution of 10 km are in good agreement with the results of NCEP (National Centers for Environmental Prediction, USA). The dose rates assessed on the basis of modeling at the points of radiation monitoring in Japan differ from results of airborne gamma survey no more than 2 times. Proposed assessments of the sources of accidental releases into the atmosphere during March 15, 2011 due to a series of accidents at the units of Fukushima-1 NPP, on the whole, correspond to the real radiation conditions. This is confirmed by the simulation results, data of dose rate measurements, results of airborne gamma survey and estimates of Cs-137 fallout based on the data of monitoring services.

Bibliographical reference 

Arutyunyan R.V., Bakin R.I., Bolshov L.A., Dzama D.V., Pripachkin D.A., Semyonov V.N., Sorokovikova O.S, Fokin A.V., Tsaun S.N., Shikin A.V. (IBRAE RAN), Ignatov R.Y., Rubinstein K.G., Smirrnova M.M. (State Institution “Hydrometeorological Centre of Russia”). Some results of modeling the radiation conditions and assessing the source term at Fukushima-1 NPP with three-dimensional fields of meteorological data. Preprint No. IBRAE-2011-07. Moscow, Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 2011, 20 p.

Preprint IBRAE-2011-06

Mitenkova E.F., Solovjeva E.V.

This work is realized as a part of  the specialized programming complex CFC_BN for fuel cycle simulation on the basis of cores in MCNP-MONTEBURNS-ORIGEN calculations. The VAR-GM is intended for generation of calculated files for fuel pins, fuel assembly at varying geometry and material parameters. Also the core variations are considered for its row and FA representation at some MCNP5 limitations of format possibilities. The VAR-GM results are represented at the applicability analyses of metallic (U-Pu-Zr) fuel in the mode of single loading for initial stage of BN-800 operation.

Bibliographical reference 

Mitenkova E.F., Solovjeva E.V. VAR-GM MODULE GENERATION OF CALCULATED FILES FOR VARYING GEOMETRY AND CORE MATERIAL PARAMETERS IN MCNP-MONTEBURNS-ORIGEN MULTIPLE CALCULATIONS. — (Preprint / Nuclear Safety Institute RAS, July 2011, № IBRAE-2011-06). — Moscow : NSI RAS, 2011. — 25 p. — Refs.: 10 items.

Preprint IBRAE-2011-05

Ahrameev E.V.

The paper presents analytical expressions for the scattering cross sections of nonrelativistic electrons on nuclei. For several real nuclei (with transitions E1 and M1) it contains calculations for: cross sections of excitation of nuclei by inelastic scattering of electrons (in the Born and nonrelativistic approximations, and using Hartree-Fock-Slater method of the self-consistent field); transport cross sections of excitation of nuclei by inelastic scattering of electrons (in the Born approximation); the efficiency of different mechanisms of excitation (inelastic scattering of electrons, the inverse internal electron conversion, excitation of the thermal radiation of the plasma).
Considered the possibility of excitation of the «combustion wave»..

Bibliographical reference 

Ahrameev E.V. MECHANISMS FOR THE EXCITATION OF ISOMER NUCLEI IN HOT DENSE PLASMA. Preprint IBRAE-2011-05. Moscow: Nuclear Safety Insitute RAS, 2011, 52 p. — Refs.: 24 items.

Preprint IBRAE-2011-05

Blokhin P.A., Mitenkova E.F.

Practical calculations of radionuclides mixture gamma-radiation require the nuclear data about the individual gamma-ray spectra while radionuclides decay. The modern versions of evaluated nuclear data files ENDF/B-VII.0 and JEFF-3.1.1 contain these data in endf-6 format. This paper presents the results of gamma-ray spectrum formation while using the specialized procedures of processing, analysis and compilation radiation data based on ENDF/B-VII.0 and JEFF-3.1.1.

Bibliographical reference 

Blokhin P.A., Mitenkova E.F. GAMMA-RAY SOURCE FORMATION OF IRRADIATED NUCLEAR FUEL ON THE BASIS OF MODERN EVALUATED NUCLEAR DATA FILES ENDF/B-VII.0 AND JEFF-3.1.1. – Preprint / Nuclear Safety Institute RAS, April 2011, № IBRAE-2011-04. – Moscow: NSI RAS, 2011. – 31 p. – Bibliogr.: 18 items.