Saint-petersburg state university russian academy of sciences joint institute for nuclear research
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- MODELLING OF THE INTERACTION OF POWERFUL RADIATION WITH A CONDENSED MATTER TARGET IN A MAGNETIC FIELD
- MONITORING SYSTEM OF RADIATION EXPOSURE PROTON LINAC
- EXPERIMENTAL STUDIES OF THE MEDICAL ISOTOPES PRODUCTION USING SPALLATION NEUTRONS GENERATED IN MASSIVE URANIUM TARGET
- SOFTWARE COMPLEX FOR SIMULATION OF INTROSCOPY AND TOMOGRAPHY SYSTEMS
- RECORDING SYSTEM OF MULTICHANNEL TEMPORAL DISTRIBUTION SPECTROMETER
- THREE-CHANNEL TEMPORAL SPECTROMETRY OF RADIATION FLUX
- FIELD GENERATED BY THE PASSAGE OF GAMMA RAYS THROUGH A LIQUID MEDIUM
- NEUTRINO EXPERIMENTS DATA BASE
THE S 3 AS AN AUXILIARY DETECTOR FOR NEUTRINO MONITORING OF A NUCLEAR REACTOR Egorov V.G. 1 , Ponomarev D.V. 1 , Rozova I.E. 1 , Fomina M.V. 1 , Kuznetsov A.S. 1 , Zhitnikov I.V. 1 , Belov V.V. 1 , Štekl I. 2 , Špavorová M. 2 , Fajt L. 2 , Vlášek J. 2 , Přidal P. 2 , Hodák R. 2 , Mamedov F. 2 , Burešova H. 3 1 Joint Institute for Nuclear Research, Dubna, Russia; 2 Institute of Experimental and Applied Physics, CTU, Prague, Czech Republic; 3 Envinet a. s., Třebíč, Czech Republic E-mail: egorov@jinr.ru One of the prospective methods of industrial nuclear reactor monitoring could be done by means of neutrino detection. In order to realize this idea it is necessary to have some relatively simple neutrino detectors, which do not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial nuclear reactor. In this work we describe design of the S 3 detector developed in JINR. The S 3 is very similar to the big DANSS detector, but has more simple construction and smaller dimensions. The sensitive volume of the detector (64 l) consists of 80 polysterene-based plastic scintillator plates. To collect light signal 8 photomultipliers and 80 multi- pixel photon counters (MPPCs) coupled to the plates via wavelength-shifting fibers are used. Each S 3 detector is expected to register that about 500 neutrino events per day with a background less than 10%; and the system consisting of the DANSS detector and two or three S 3 detectors renders it possible to determine the center of fuel burning in the WWER-1000 reactor with the accuracy of 10–20 cm. 305 MODELLING OF THE INTERACTION OF POWERFUL RADIATION WITH A CONDENSED MATTER TARGET IN A MAGNETIC FIELD Kuzenov V.V. 1,2 , Ryzhkov S.V. 1 , Shumaev V.V. 1 1 Bauman Moscow State Technical University, Moscow, Russia; 2 Institute for Problems in Mechanics of RAS, Moscow, Russia E-mail: shumaev@student.bmstu.ru High energy density systems, such as magneto-inertial fusion devices [1, 2] can be used for a wide range of applications: as a particle source for disposal of radioactive wastes and medical applications of isotopes, as part of the fusion- fission reactor, for experiment with materials and etc. The significant feature of these systems is an ultrahigh magnetic field (~10 4 T during target compression) [3, 4]. It is required to consider the processes of the target compression together with equations of state (thermal and thermodynamic) at various stages, including maximum compression, i.e. for a wide range of density and temperature (temperatures from a few thousands K to a hundred millions K, densities from gas-like up to 10 7 kg/m 3 ). Obtaining the equations of state in such a wide range of parameters leads to the problem of joining the solutions. Relatively simple and sufficiently accurate option is to use the Thomas-Fermi model at high temperatures and densities (temperature T > 10 5 K, the density of the order of solid density and higher) [5–7]. One can use the ionization equilibrium model (Saha model) [5, 8] for lower temperatures and densities. This paper describes the following subtasks arising from modeling of the interaction of powerful radiation with a condensed target in an external magnetic field: physical context and mathematical formulation of the problem; the calculation of the thermodynamic properties (pressure, specific internal energy and entropy) of plasma on the basis of wide-range equation of state. The calculation results in the temperature-density coordinates are presented. Criteria for the use of each model are obtained. This work was supported by the Ministry of Education and Science of the Russian Federation (Project № 13.79.2014/K). 1. O.V.Gotchev, P.Y.Chang, J.P.Knauer et al. // Phys. Rev. Lett. 2009. V.103. 215004. 2. V.V.Kuzenov, S.V.Ryzhkov // Probl. Atom. Sci. Tech. 2013. № 1 (83). P.12. 3. S.V.Ryzhkov // Bull. Russ. Acad. Sci.: Phys. 2014. V.78. P.456. 4. D.Nakamura, H.Sawabe, S.Takeyama // Rev. Sci. Instrum. 2014. V.85. 036102. 5. Ya.B.Zel’dovich, Yu.P.Raizer. Physics of Shock Waves and High-Temperature Hydrodynamic Phenomena. New York: Dover Publications. 2002. P.944. 6. A.F.Nikiforov, V.G.Novikov, V.B.Uvarov. Quantum-Statistical Models of Hot Dense Matter. Methods for Computation Opacity and Equation of State. Basel: Birkhauser Verlag. 2005. P.439. 7. V.V.Kuzenov, S.V.Ryzhkov, V.V.Shumaev // Applied Physics. 2014. V.3. P.22. 8. N.N.Kalitkin, K.I.Lutskiy // Doklady Akademii Nauk. 2014. V.457. P.157. 306 MONITORING SYSTEM OF RADIATION EXPOSURE PROTON LINAC Skorkin V.M. 1 , Belyanski K.L. 1 , Skorkin A.V. 2 1 Institute for Nuclear Research of RAS, Moscow, Russia; 2 VERCOM, Moscow, Russia E-mail: skorkin@inr.ru A result of the proton beam loss is formed radionuclides, gamma and neutron secondary radiation, which represent danger to the personnel and the population. The main radiation hazard to population is short-lived radionuclides in atmospheric radioactive emissions from the linac. The monitoring system online controls the neutron radiation from the beam loss, the gamma-activity of radioactive gases and aerosols in the ventilation system of the linac and a dose rate from an external gamma and beta radiation near to urban area. The system consists of neutron detectors in transport channels, gamma detectors in the ventilation system and the distributed network DKS-AT1121 dosimeters placed in territory. The detectors are connected to the server through data cable. The central server performs the storage and processing of data from the sensors, the display card detectors, the spectra and the measurement results, the presentation of the results in text and graphical form on a Web page. 307 EXPERIMENTAL STUDIES OF THE MEDICAL ISOTOPES PRODUCTION USING SPALLATION NEUTRONS GENERATED IN MASSIVE URANIUM TARGET Sotnikov V. 1 , Adam J. 2 , Artushenko M. 1 , Solnyshkin A. 3 , Tyutyunnikov S. 3 , Voronko V. 1 , Zavorka L. 4 , Zhadan A. 1 1 National Science Centre Kharkov Institute of Physics and Technology, Kharkov, Ukraine; 2 Nuclear Physics Institute of the ASCR, Řež, Czech Republic; 3 Joint Institute for Nuclear Research, Dubna, Russia; 4 Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Prague, Czech Republic E-mail: sotnik@kipt.kharkov.ua Most of the discussed or projected electronuclear systems (Accelerator Driven Systems) are a hybrid of the subcritical fast reactor (sub-critical core) and external neutron source (spallation target) based on the accelerator. Sub- critical core implemented neutron spectra close to moderated fission neutron spectrum and in these spectra one can produce radionuclides typical for fast nuclear reactor. Neutron spectrum in the spallation target more hard than fission neutron spectrum. This spectrum will allow produce some medical isotopes by spectral neutrons with energy > 10 MeV. We investigated the production possibility of the therapeutic radionuclides 64,67 Cu and alpha emitter 225 Ac( 213 Bi) via nat Zn(n,x) and 232 Th(n,x) reactions induced by fast spallation neutrons generated by 1–8 GeV deuteron and 660 MeV proton beams. Experiments was performed on a massive uranium target (mass of natural uranium ~ 512 kg) of assembly "QUINTA-M" [1] at the accelerators “Nuclotron” and “Phasotron” JINR , Dubna. It was found that all reaction rates, calculated per unit of beam power, remains approximately constant within our statistical errors for all energies of the deuteron beam in the range from 1 to 8 GeV. During a saturation irradiation, it is possible to produce 2.4 GBq of 67 Cu per gram of natural Zn and per 1 MW primary beam power. Saturation yield of 64 Cu is 49 GBq/g/MW. In this work we performed calculation of radionuclide purity depending on the degree of enrichment of the various zinc isotopes and depending on the ‘cooling’ time after irradiation. The main disadvantage of this method is a high 64 Cu/ 67 Cu ratio in the final product at EOB. Significantly reduce 64 Cu/ 67 Cu ratio is only possible if you use zinc target enriched with 68 Zn. Satisfactory result can be expected for the enrichment starting with 50% 68 Zn. 1. J.Adam et al. (“E&T–RAW” Collaboration) // JINR Preprint E1-2010-61. Dubna. 2010. 308 THE USE OF THE 120-CM CYCLOTRON FOR THE STUDY OF COMBINED EFFECT OF IONIZING RADIATION AND HYPOMAGNETIC CONDITIONS ON THE LETTUCE SEEDS Lebedev V.M. 1 , Platova N.G. 2 , Spassky A.V. 1 , Trukhanov K.A. 2 1 Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, Moscow, Russia; 2 State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia E-mail: wg2@anna19.sinp.msu.ru Study of biological effect of high energy charged particles and hypomagnetic conditions (HMC) is an actual interdisciplinary task that is important for human activities and functioning of the future bioregenerative life support systems (BLSS) for astronauts in deep space and on the Moon. Using the 120-cm cyclotron we studied the effect of -particles under conditions of normal and low geomagnetic field on chromosomal damage lettuce seeds Latuca sativa L., belonging to the intended composition BLSS during long distant flights. Irradiation of seeds carried out in cells with walls made of thin mylar films. The seeds were placed between the two films in a single layer. Irradiation was carried out sequentially on both sides of the cell. Energy of -particles bombarding seeds was 25.8 MeV. The magnitude of the linear energy transfer (LET) at the same time close to the value of LET relativistic nuclei neon- magnesium galactic cosmic rays, which allows you to simulate their effect on biological objects. To create HMC conditions used hypomagnetic cylindrical chamber of a soft magnetic material with a working volume of 28 liters, in which the geomagnetic field has been weakened by more than 1000 times. Irradiated seeds with different values of absorbed doses were germinated in a different attenuation of the geomagnetic field. The result of exposure to ionizing radiation and the HMC was estimated by the number of chromosomal damages in first mitosis of seedling root meristem. As a result of the experiments there was a trend to increased levels of chromosomal aberrations in irradiated seeds. Under cytogenetic analysis after germination of irradiated and non-irradiated seeds in HMC there was observed a tendency of increase in the percentage of chromosomal aberrations, cells with multiple aberrations, as well as the percentage of chromosomal bridges in comparison with seeds, germinated in the laboratory condition. The work was performed by using equipment purchased by "Program for Development of Moscow University." 309 SOFTWARE COMPLEX FOR SIMULATION OF INTROSCOPY AND TOMOGRAPHY SYSTEMS Spirin D.O., Berdnikov Ya.A. Peter the Great St.Petersburg Polytechnic University, Saint-Petersburg, Russia E-mail: dspirin@phmf.spbstu.ru Present simulation software of introscopy and tomography. Software complex allows for required mathematical and computer processing and visualization of the results of recognition. The report is devoted to development and testing of a program complex for an industrial X-ray tomography with application of the dual energy method. The purposes of the project also include creation of full-scale realistic modelling (simulator) of an industrial X-ray tomography. It is shown, that the analysis, development and application of a dual-energy method of in an industrial tomography will give new quality of the restored tomograms and will allow to obtain a new information about research object. Dual-energy method allows to obtain the atomic number and density by linear attenuation coefficient examination at two different energies [1]. The possibility of the dual-energy method application in X-ray CT was examined with the use of X-ray CT simulating. The software complex was developed for full-scale realistic modeling of the X-ray tomography from a stage of reception of projective data till restoration of the image of investigated object [2]. The obtained results and the developed software will be used in researches made on the industrial X-ray tomography on faculty «Experimental nuclear physics» SPbPU. Also it is possible to use the obtained results in development of other tomography systems for simulation, testing and data processing from corresponding facilities. 1. R.E.Alvarez et al. // Phys. Med. Biol. 1976. V.21. P.733. 2. S.Agostinelli et al. // NIM in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 2003. V.506. №3. P.250. 310 RECORDING SYSTEM OF MULTICHANNEL TEMPORAL DISTRIBUTION SPECTROMETER Akindinova E.V., Babenko A.G., Vakhtel V.M., Rabotkin V.A., Kharitonova D.D. Voronezh State University, Voronezh, Russia E-mail: vakhtel@phys.vsu.ru A system of measurement of temporal properties of radiation fluxes has been developed on the basis of a spectrometer consisting of four independent parallel measurement channels, including points of time t i of arrival from four radiation detectors. Each channel of a spectrometer version created has a spectrometric amplifier, a differential amplitude discriminator, and a standard signal conditioner. Pulses from each channel are received by a multichannel meter-counter recording the point of time of arrival of pulse sequences. A software package of buffer memory channel control for channels with FIFO structure has been developed to assure the optimum management of accumulation of sequences t i arrays. The error of time point determination amounts to 2.5 10 –7 s. The systems allows for the off-line scanning of t i arrays accumulated and forming of the corresponding arrays of time intervals i = t i+1 – t i and number n( t) of particles during interval t. Such approach allows, without losing any information on time characteristics of radiation fluxes, the forming of time series of the required structure for further statistical analysis. 311 THREE-CHANNEL TEMPORAL SPECTROMETRY OF RADIATION FLUX Akindinova E.V., Babenko A.G., Vakhtel V.M., Zyulkov A.V., Rabotkin V.A., Kharitonova D.D. Voronezh State University, Voronezh, Russia E-mail: vakhtel@phys.vsu.ru Three-channel measurements of sequences of points of time t i of generation of semiconductor detector pulses at recording of alpha-radiation from reference source 238 Pu have been carried out. The measurements were performed with the help of a three-channel spectrometer of temporal distributions of t i . The duration of continuous measurement amounted up to 18 days. The error of determination of t i did not exceed 2.5 10 –7 s. The accumulated arrays of time sequences t i were off-line formed into the arrays of time serieses n( t) of the number of pulses during the specified intervals of time t>10 –1 s. The stability of measurement conditions, i.e. stationary state, was monitored as per the parameters of amplitude spectra of alpha particles of each channel. Time serieses n( t) obtained with the volume of up to 1.510 6 were processed with the help of correlation analysis and spectral Fourier analysis. The autocorrelation function was applied as follows: ) ( ) , cov( ) , ( n S n n n n R k i i k i i , where ) , cov( k i i n n and S – autocorrelation function and dispersion respectively. The correlation and spectral Fourier analysis of functions ) , ( k i i n n R was carried out with several standard windows – weight functions used. Moreover, the cross-correlation analysis of time serieses of all three channels was performed. No fluctuations of values of n( t) with periods of 1 min ≤ T ≤ 48 hours have been observed for the significance level of 0.95 and 0.99. 312 FIELD GENERATED BY THE PASSAGE OF GAMMA RAYS THROUGH A LIQUID MEDIUM Valiev F.F. Saint-Petersburg State University, Russia E-mail: valiev@hiex.phys.spbu.ru The electromagnetic field generated by the interaction of hard gamma radiation with the liquid media was studied even in beginning of the last century [1, 2]. The general approach to calculation of the field in space-time representation is presented in [3]. Many works were performed in this approach in the frame of the linear current model [4, 5]. Here we calculated the components of electromagnetic field produced with gamma radiation passing through the media as liquid as gaseous for comparison. We summed the fields of the free electrons resulting from interaction of gamma radiation with media. There is difference in data for total sources of electromagnetic fields at fixed observation’s angels in these media. Result decreases with the increasing of pressure of gaseous medium. 1. P.A.Cerenkov // Doklady Akad. Nauk SSSR. 1934. V.2. P.451. 2. I. M.Frank, I.E.Tamm // Doklady Akad. Nauk SSSR. 1937. V.14. P.109. 3. V.V.Borisov. The electromagnetic field of the transient currents. 1996. St-Petersbug State University Press. St-Petersbug. 4. V.V.Borisov, A.B.Utkin // J. Phys. 1993. A. V.26. P.4081. 5. F.F.Valiev // Bulletin of the Russian Academy of Sciences: Physics. 2011. V.75. №7. P.1001. 313 NEUTRINO EXPERIMENTS DATA BASE Brusnitcyn A.A. 1 , Shirokov E.V. 1,2 , Stepanov M.E. 1 , Vladimirova E.V. 1 1 Faculty of Physics, Lomonosov Moscow State University, Moscow, Russia; 2 Skobeltzyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia E-mail: elena.v.vladimirova@gmail.com Detection of neutrinos is one of the highest priorities for the scientific community now. Neutrino carries unique information about important processes from the depths of the Earth and out from deep space. Meanwhile there is no database that accumulates the results of a large number of experiments. The unified database for neutrino experiments is presented. The resulting database allows to add, store, and search for a variety of data, such as general information about the experimental complex, parameters of the detector, purposes of the experiment, characteristics of the neutrino, experimental points, as well as information about the participants of the experiment and related publications. The adding data interface is implemented so that the user can quickly and easily edit the stored information. Web database interface also enables a flexible search of the stored data and presents the result in the most convenient form. The main tools for implementation of a relational database and control interface are SQL (structured query language), PHP, JavaScript, and JSON (JavaScript Object Notation). The database and control interface provides the open internet access. The database is running at SINP MSU (Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University) at present, and it is in the process of loading the experimental data now. |
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