Nuclear dissipative dynamics in langevin approach

Tanrıverdi, Vedat
In this thesis Langevin approach is applied to analyze the nuclear dissipative dynamics in fission and fusion reactions. In these investigations, the nuclear elongation coordinate and the corresponding momentum are chosen as collective variables. By considering changes in these variables the decay rate of fission and the formation probability of fusion for heavy ion reactions are calculated. These calculations are performed using simulation techniques and the results thus obtained are compared with the corresponding results of analytic solutions.


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Employing a quantal diffusion description based on the stochastic mean-field approach, we analyze the mass distribution of the primary fragments in the collisions of the Xe-136 + Pb-208 system at the bombarding energy E-c.m. = 526 MeV. This quantal approach provides a good description of the primary fragment distribution without any adjustable parameter, including the effects of shell structure
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Danışman, Betül; Yılmaz, Osman; Department of Physics (2011)
The nuclear matter liquid-gas phase transition is expected to be a signal of nuclear spinodal instabilities as a result of density fluctuations. Nuclear spinodal instabilities in symmetric nuclear matter are studied within a stochastic relativistic density-dependent model in semi-classical approximation. We use two parameterization for the Lagrange density, DDME1 and TW sets. The early growth of density fluctuations is investigated by employing relativistic Vlasov equation based on QHD and discussed the clu...
Spinodal instabilities in nuclear matter in a stochastic relativistic mean-field approach
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Spinodal instabilities and early growth of baryon density fluctuations in symmetric nuclear matter are investigated in the basis of the stochastic extension of the relativistic mean-field approach in the semiclassical approximation. Calculations are compared with the results of nonrelativistic calculations based on Skyrme-type effective interactions under similar conditions. A qualitative difference appears in the unstable response of the system: the system exhibits most unstable behavior at higher baryon d...
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Jacquot, B; Colonna, M; Ayik, S; Chomaz, P (Elsevier BV, 1997-05-12)
Early development of the instabilities in a dilute nuclear source is investigated using a finite temperature quantal RPA approach for different systems, The growth rates of the unstable collective modes are determined by solving a dispersion relation, which is obtained by parametrizing the transition density in terms of its multipole moments. Under typical conditions of a dilute finite system at moderate temperatures the dispersion relation exhibits an ultraviolet cut-off. As a result, only a finite number ...
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The nucleon electromagnetic form factors are calculated in a light cone QCD sum rules framework using the most general form of the nucleon interpolating current. Using two models for the distribution amplitudes, we predict the form factors. The predictions are also compared with existing experimental data. It is shown that our results describe remarkably well the existing experimental data.
Citation Formats
V. Tanrıverdi, “Nuclear dissipative dynamics in langevin approach,” M.S. - Master of Science, Middle East Technical University, 2004.