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The light charged particle evaporation from the compound nucleus and from the complex fragments in the reactions S+Mo, Sb+Al, Ar+Dy, and Ar+Ag is studied within the dinuclear system model. The possibility to distinguish the reaction products from different reaction mechanisms is discussed. [ABSTRACT FROM AUTHOR]

Within the quantum diffusion approach, the capture of a projectile nucleus by a target nucleus is studied at bombarding energies above and below the Coulomb barrier. The effects of deformation of interacting nuclei and neutron transfer between them on the total and partial capture cross sections and the mean angular momentum of the captured system are studied. The results obtained for the O + Cd, Sm, and W; F +Lu; Si +Mo and Sm; Ca +Zr; Ca+ Zr; and Ni +Ni, Zr, and Mo reactions are in good agreement with available experimental data. [ABSTRACT FROM AUTHOR]

The quantum diffusion approach is applied to study the isotopic dependencies of capture cross section and mean-square angular momentum in the reactions 48Ca + 144;150;154Sm and 40Ca + 154Sm. [ABSTRACT FROM AUTHOR]

The hyperdeformed nuclei treated as dinuclear or quasimolecular configurations are suggested to be directly produced in heavy-ion reactions at bombarding energies near the Coulomb barrier. [ABSTRACT FROM AUTHOR]

Within the dinuclear system model we analyse the production of yet unknown superheavy nuclei in actinide-based complete fusion reactions. The yields of superheavies with Z > 118 are sensitive to the location of the next proton shell closure beyond 208Pb. [ABSTRACT FROM AUTHOR]

The cold cluster decay model is presented in the framework of a dinuclear system concept. Spectroscopic factors are extracted from barrier penetrabilities and measured half-lives. The deformation of the light cluster and residual nucleus is shown to affect the nucleus–nucleus potential and decay characteristics. Half-lives are predicted for neutron-deficient actinides and intermediate-mass nuclei. The connection between spontaneous fission and cluster radioactivity is discussed.© 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

An analysis of the preferable fission path manifesting itself as a fine structure of the total kinetic energy–mass distribution of the fission fragments compelled us to put forward an absolutely new shape of the fissioning system on the descent from the fission barrier. It is a multicomponent nuclear molecule constituted by two magic clusters and a torus-like neck between.© 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The production of hassium isotopes266-271 Hs in various reactions 22Ne + 249Cf, 25.26Mg + 248Cm, 30Si + 244Pu, 34.36S + 238U, 40Ar + 232Th, and 48Ca + 226Ra is studied within the dinuclear system model. The experimental excitation functions of the isotopes266-271 Hs are well described and predictions are made for future experiments. [ABSTRACT FROM AUTHOR]

The sub-barrier capture (fusion) reactions 32S + 94,96Zr and 40Ca + 94,96Zr, and 48Ca + 90,96Zr with positive and negative Q values for neutron transfer are studied with the quantum diffusion approach and the universal fusion function representation. For these systems, the 5-wave capture probabilities are extracted from the experimental excitation functions and are also analyzed. Different effects of the positive Qxn-value neutron transfer in the fusion enhancement are revealed in the relatively close reactions 32S + 94,96Zr and 40Ca + 94,96Zr. [ABSTRACT FROM AUTHOR]

The possibilities of production of the doubly magic nucleus 100Sn in complete fusion and quasifission reactions with stable and radioactive ion beams are investigated within a dinuclear system model. The excitation functions for production of the exotic nuclei 100-103Sn and 112,114Ba via xn, pxn, a xn, and 12,14Cxn emission channels are predicted for future experiments. [ABSTRACT FROM AUTHOR]

The relationship between the backward elastic scattering probabilities and the reaction cross sections is derived. This is a very simple and useful method to extract reaction cross sections for heavy-ion systems. We compare the results of our method with those that use the traditional full elastic scattering angular distributions for several systems at energies near and above the Coulomb barrier. From the calculated reaction and capture cross sections that use the present method, we derive the cross sections of other mechanisms for weak nearly spherical systems. [ABSTRACT FROM AUTHOR]

The relationship between the quasi-elastic excitation function and the capture cross section is derived. The quasi-elastic data is shown to be a useful tool to extract the capture cross sections and the angular momenta of the captured systems for the reactions 160 + 144,154Sm,208Pb, 20Ne + 208Pb, and 32S + 90.96Zr near and above the Coulomb barrier energies. [ABSTRACT FROM AUTHOR]

Comparing the capture cross sections calculated without the breakup effect and experimental complete fusion cross sections, the breakup was analyzed in reactions with weakly bound projectiles 6,7,9Li, 9,11Be, and 6,8He. A trend of systematic behavior for the complete fusion suppression as a function of the target charge and bombarding energy is not achieved. The quasielastic backscattering is suggested as a useful tool to study the behavior of the breakup probability in reactions with weakly bound projectiles. [ABSTRACT FROM AUTHOR]

The article presents the experimental developments in nuclear physics. It presents the study which examined the influence of neutron transfer in reactions with weakly and strongly bound nuclei on the sub-barrier capture process. In the study, the quantum diffusion approach was used. Based on the results, the neutron transfer with positive Q value has little influence in the sub-barrier capture of the colliding nuclei.

The role of prolate and oblate deformations of colliding nuclei in the sub-barrier capture process is studied within the quantum-diffusion approach. A comparison of the calculated and measured capture cross sections in the reactions 160, 48Ca + 154Sm and 74Ge + 74Ge show that transitions during the capture process occur from the potential minimum with an oblate deformation of the ground state to the minimum with a prolate deformation of the nuclei 154Sm and 74Ge. These transitions crucially influence the sub-barrier capture. The capture cross sections and mean-angular momenta are predicted for the reactions of 36S + 170Er, 174Yb. [ABSTRACT FROM AUTHOR]

The roles of nuclear deformation and neutron transfer in sub-barrier capture process are studied within the quan-tum diffusion approach. The change of the deformations of colliding nuclei with neutron exchange can crucially influence the sub-barrier fusion. The comparison of the calculated capture cross section and the measured fusion cross section in various reactions at extreme sub-barrier energies gives us information about the quasifission. [ABSTRACT FROM AUTHOR]

The influence of entrance channel isospin, charge asymmetry, and bombarding energy on the competition between the complete fusion followed by the decay of compound nucleus and quasifission channels is treated within the dinuclear system model. The charge (mass) distributions of the products in the reactions 16.220+27Al, 92,78Kr+40Ca, 86Kr+48Ca,122Sn+12C, 32S+100Mo, 48Ca+144,154Sm, and 20,28Ne+181Xa are calculated at bombarding energies above the Coulomb barrier. The evolution of charge distribution of the complex fragments from the excited rotating nucleus 134Xe with increasing angular momentum and excitation energy is demonstrated. [ABSTRACT FROM AUTHOR]

The possibilities of direct production of the isotopes of transfermium nuclei 259,260Md, 260,261No, 261-264Lr, 264,265Rf, 264-268Db, 266-269Sg, 266-271Bh, 267-274Bh, and 270-274Mt in various asymmetric hot fusion-evaporation reactions are studied. The excitation functions of the formation of these isotopes in the αxn and pxn evaporation channels are predicted for the first time. The optimal reaction partners and conditions for the synthesis of new isotopes are suggested. The products of the suggested reactions can fill a gap of unknown isotopes between the isotopes of heaviest nuclei obtained in the xn evaporation channels of the cold and hot complete fusion reactions. [ABSTRACT FROM AUTHOR]

Within the quantum diffusion approach, the capture process of a projectile nucleus by a target nucleus is studied at bombarding energies above and below the Coulomb barrier. The entrance channel effects on the partial and total capture cross sections and the mean angular momentum of the captured system are studied in the reactions leading to 156,160Er, 170Hf, 200Pb, 216Ra, and 220Th compound nuclei. [ABSTRACT FROM AUTHOR]