

Physics of Elementary Particles and Atomic Nuclei

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Adamian G.G., Antonenko N.V., Kalandarov Sh.A. Description of the Quasifission Reactions in the Framework of Dinuclear System Model (rus, 1.8 Mb) Formation and evolution of dinuclear system in quasifission reactions are considered. In the framework of dinuclear system concept the processes of formation of reaction products are investigated. Isotopic dependence of formation cross sections of superheavy nuclei in quasifission reactions is considered. The yields of new neutronrich isotopes of nuclei with Z = 64  80 in quasifission reactions are predicted. The mechanism of complex fragment formation in complete fusion and quasifission reactions is analyzed. 

Artukh A.G., Klygin S.A., Kononenko G.A., Kyslukha D.A., Lukyanov S.M., Mikhailova T.I., Oganessian Yu.Ts., Penionzhkevich Yu.E., Sereda Yu.M., Vorontsov A.N., Erdemchimeg B. Radioactive Nuclear Beams of COMBAS Facility (eng, 1.2 Mb) The basic ionoptical characteristics of the highluminosity and highresolution kinematic separator COMBAS, realized for the first time on the strong focusing principle, are presented. The developed facility allows one to separate the highintensity secondary radioactive beams in a wide range of mass numbers A and atomic numbers Z, which are produced in heavyion reactions in the energy range of 20 E 100 MeV/A (Fermi energy domain). Two distinct detector systems, such as realized Si stripdetector telescope and the threedimensional timeprojection chamber of promising development, are discussed. A program of the investigations of nuclear reaction mechanisms at intermediate energies of 20100 MeV/A, measurement of the radii of unstable nuclei, study of the cluster structure of light nuclei near the nuclear dripline, and search for ^{26,28}Î resonances in exchange reactions is proposed. The upgrading of experimental facility by the integration of COMBAS separator with the ion catcher is discussed. 

Tsyganov Yu.S. Experiment Automation at the Dubna GasFilled Recoil Separator (rus, 3.3 Mb) Different approaches to solving tasks related to the automation of main processes in longterm experiments with heavyion beams at the Dubna gasfilled recoil separator (DGFRS) are examined. Techniques in the field of spectroscopy of rare decays of superheavy nuclei and approaches to the development of control systems which ensure failsafety when conducting experiments with extremely radioactive targets and registration of the main parameters of experiments are described. The specificity of DSSSD (Double Side Silicon Strip Detector) detectors is examined. A special emphasis is placed on the role of edge phenomena of neighboring pn junctions when the method for "active correlations" is applied. An example of a beamfree experiment is briefly examined in an attempt to observe the Zeno effect. The main examples are specified for nuclear complete fusion reactions with beams of ^{48}Ca accelerated by the U400 cyclotron at FLNR, JINR. 

Zalikhanov B.Zh. From the Electron Avalanche to Lightning Discharge (rus, 650 Kb) The work gives a qualitative description of the physics of the processes beginning with an electron avalanche and ending with a lightning discharge. A streamer model is considered that is based on the investigation of the observed new processes occurring in the prestreamer region. The study and analysis of these processes allow a conclusion that they are actually accompanying processes to support transition of an electron avalanche to a streamer and can be interpreted as a manifestation of the properties of the double charge layer in an external electric field. Important problems of physical processes underlying formation of a lightning discharge are considered on the basis of the new concept of streamer formation and intergrowth. Causes for coherent microwave leader radiation and neutron generation in a lightning discharge that have not yet been explained in the gas discharge theory are disclosed. A simple globe lightning model is also proposed on the basis of the new concept, which allows answering all questions arising from the observation of the globe lightning behavior, and a necessity of changing over from the traditional lightning rod to a lightning guard of a new design is discussed. 

Synopsis (rus, 51 Kb) 

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Part 2  up 
Rodionov V.N., Kravtsova G.A. Algebraic PTSymmetric Quantum Theory with a Maximal Mass (rus, 400 Êb) In this article we want to draw attention to the fact that the approaches developed by V.G.Kadyshevsky in the course of several decades and devoted to the geometric construction of quantum field theory with fundamental mass containing nonHermitian mass extensions have recently gained a powerful development in the form of construction of the nonHermitian algebraic approach. The central point of these theories is the construction of new scalar products in which the average values of nonHermitian Hamiltonians are valid. Among numerous works on this subject there are both purely mathematical and containing a discussion of experimental results. In this regard, we consider the development of algebraic relativistic pseudoHermitian quantum theory with a maximal mass and discuss its experimentally significant consequences. 

Sargsyan V.V., Kanokov Z., Adamian G.G., Antonenko N.V. Application of the Theory of Open Quantum Systems in Nuclear Physics (rus, 3550 Êb) Quantum diffusion equations with transport coefficients, explicitly depending on time, are derived from the generalized nonMarkovian Langevin equations. The asymptotic behavior of the friction and diffusion coefficients is studied in the cases of FC and RWAcouplings between the collective and internal subsystems. The asymptotics of the propagator of the density matrix of open quantum system is obtained in the general case of quadratic Hamiltonian linearly coupled (in coordinate and momentum) with internal degrees of freedom. The influence of different sets of transport coefficients on decoherence and decay rate of the metastable state is studied by using the master equation for the reduced density matrix of open quantum systems. The developed approach is used to study the capture of the projectile by the target nucleus at energies near the Coulomb barrier. With the calculated capture probabilities, a good agreement between the calculated capture cross sections and experimental data is obtained. Specific cases where the dissipation promotes penetration through the potential barrier are revealed. The analytical derivation of the generalized Kramers formula is presented for the quasistationary decay rate of quantum metastable systems. 

Kuklin S.N., Adamian G.G., Antonenko N.V. Description of Alpha Decay and Cluster Radioactivity in the Dinuclear System Model (rus, 500 Êb) The description of the cluster radioactivity and decay of the cold nuclei is suggested in the dinuclear system model. The quantum fluctuation of the dynamic coordinate in the charge (mass) asymmetry determines the value of spectroscopic factor, and tunneling in the coordinate relative distance determines the amount of the barrier penetrability of the nucleusnucleus interaction potential. A new method of calculation of the spectroscopic factor is suggested. The hindrance factors for the transfer of orbital angular momentum are studied. For decays of neutrondeficient nuclei ^{194,196}Rn, we give the possible explanation of the deviations of the halflives from the GeigerNuttall law. The fine structure of decays of isotopes of U and Th is described and predicted. The model is employed to describe the decay from the states of the rotational band of the eveneven nuclei. For the regions of "lead" and "tin" cluster radioactivities, the halflives are well described and the most probable cluster yields are predicted. The cluster decay from the excited nuclei is considered. The connection of cluster radioactivity with spontaneous fission as well as with highly deformed nuclear states is discussed. 

Logachev P.V., Meshkov O.I., Starostenko A.A., Nikiforov D.A., Andrianov A.V., Maltseva Yu.I., Levichev A.E., Emanov F.A. NonDestructive Diagnostic Methods for the Charged Particle Beams (rus, 2025 Êb) The article provides an overview of the main methods of the nondestructive diagnostic and losses registration of the charged particle beams used in the accelerator technology. It can help to choose diagnostic and beam loss registration systems, and gives the qualitative understanding of the devices operation principles. Quantitative characteristics are presented for each type of diagnostic to define the boundaries of the application. 

Gongadze A.L. Micromegas Chambers for the Experiment ATLAS at the LHC (rus, 2007 Êb) The increase in luminosity and energy of the LHC in the next upgrade (Phase1) in 20182019 will lead to a significant increase in radiation load on the ATLAS detector, primarily in the areas close to the interaction point of the LHC proton beams. One of these regions is the Small Wheel of the ATLAS Muon Spectrometer. It is planned to replace it with the New Small Wheel that will have Micromegas chambers as main coordinate detectors. The paper gives an overview of all existing types of Micromegas detectors with special focus on the Micromegas chambers for the ATLAS detector upgrade. 

Synopsis (rus, 52 Kb) 

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V. A. Matveev
V. L. Aksenov, Nguen Van Hieu
A. B. Arbuzov,
V. A. Bednyakov,
V. V. Burov,
M. A. Vasiliev,
V. V. Voronov,
R. V. Jolos,
P. I. Zarubin,
G. M. Zinovjev,
A. P. Isaev (Secretary),
E. A. Krasavin,
N. V. Krasnikov,
O. N. Krokhin,
R. Lednicky,
E. V. Lychagin,
I. N. Meshkov,
D. Nagy,
Yu. Ts. Oganessian,
A. G. Popeko,
A. A. Starobinskii,
Ch. Stoyanov,
Gh. Stratan,
G. V. Trubnikov,
V. I. Yukalov
G. V. Fedorova
Tel.:
(49621) 62650
FAX: +7(49621)65892
Email: pepan@jinr.ru
G. I. Smirnov