Nuclear Physics and Atomic Energy

ядерна ф≥зика та енергетика
Nuclear Physics and Atomic Energy

  ISSN: 1818-331X (Print), 2074-0565 (Online)
  Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine
  Languages: Ukrainian, English, Russian
  Periodicity: 4 times per year

  Open access peer reviewed journal


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Nucl. Phys. At. Energy 2015, volume 16, issue 2, pages 115-123.
Section: Nuclear Physics.
Received: 16.03.2015; Accepted: 11.06.2015; Published online: 20.07.2015.
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Statistical density of nuclear excited states

V. M. Kolomietz*

Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine

*Corresponding author. E-mail address: vkolom@kinr.kiev.ua

Abstract: A semi-classical approximation is applied to the calculations of single-particle and statistical level densities in excited nuclei. Landau's conception of quasi-particles with the nucleon effective mass m* < m is used. The approach provides the correct description of the continuum contribution to the level density for realistic finite-depth potentials. It is shown that the continuum states does not affect significantly the thermodynamic calculations for sufficiently small temperatures T ≤ 1 MeV but reduce strongly the results for the excitation energy at high temperatures. By use of standard Woods - Saxon potential and nucleon effective mass m* = 0.7m the A-dependency of the statistical level density parameter K was evaluated in a good qualitative agreement with experimental data.

Keywords: level density, excited nuclei, nuclear temperature, nucleon effective mass, continuum levels.

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