Accurate knowledge of the nuclear level density is important both from atheoretical viewpoint as a powerful instrument for studying nuclear structureand for numerous applications. For example, astrophysical reactions responsiblefor the nucleosynthesis in the universe can be understood only if we know thenuclear level density. We use the configuration-interaction nuclear shell modelto predict nuclear level density for all nuclei in the $sd$-shell, both totaland for individual spins (only with positive parity). To avoid thediagonalization in large model spaces we use the moments method based onstatistical properties of nuclear many-body systems. In the cases where thediagonalization is possible, the results of the moments method practicallycoincide with those from the shell-model calculations. Using the computed leveldensities, we fit the parameters of the Constant Temperature phenomenologicalmodel, which can be used by practitioners in their studies of nuclear reactionsat excitation energies appropriate for the $sd$-shell nuclei.
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