Spinodal instabilities in symmetric nuclear matter within a nonlinear relativistic mean-field approach

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2011

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Acar, Fatma

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Spinodal instability mechanism and early development of density fluctuations for symmetric nuclear matter at finite temperature are studied. A stochastic extension of Walecka-type relativistic mean-field model including non-linear self-interactions of scalar mesons with NL3 parameter set is employed in the semi-classical approximation. The growth rates of unstable collective modes are investigated below the normal density and at low temperatures. The system exhibits most unstable behavior in longer wave lengths at baryon densities ρB = 0.4 ρ0 , while most unstable behavior occurs in shorter wavelengths at lower baryon densities ρB = 0.2 ρ0 . The unstable response of the system shifts towards longer wavelengths with the increasing temperature at both densities. The early growth of the density correlation functions are calculated, which provide valuable information about the initial size of the condensation and the average speed of condensing fragments. Furthermore, the relativistic results are compared with Skyrme type non-relativistic calculations. Qualitatively similar results are found in both non-relativistic and relativistic descriptions.

Subject Keywords

Nuclear physics., Nuclear structure., Nuclear reactions.

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http://etd.lib.metu.edu.tr/upload/12613472/index.pdf
https://hdl.handle.net/11511/20743

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

F. Acar, “Spinodal instabilities in symmetric nuclear matter within a nonlinear relativistic mean-field approach,” M.S. - Master of Science, Middle East Technical University, 2011.