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要旨:
The present thesis is dedicated to the Schottky mass spectrometry of heavy neutronrich
nuclides between proton shell closures at Z = 50 and 82. This region on the chart
of nuclides is not well-studied, though masses of these nuclides are indispensable for our
understanding of nuclear structure and in turn of r-process nucleosynthesis. The measurements
were conducted in 2009 at GSI employing 197Au fragmentation to produce nuclei of
interest. The experiment, data acquisition and data analysis are described in detail in this
work. The data analysis was performed with two independent methods, namely spline and
correlation-matrix approaches, advantages and disadvantages of which were investigated.
The obtained results contain masses for nine nuclides, 181;183Lu, 185;186Hf, 187;188Ta, 191W
and 192;193Re, which were measured for the first time. Furthermore, mass uncertainties for
three nuclides, 189;190W and 195Os, were improved. New data were used to investigate nuclear
structure in this region. Correlations in behavior of two-neutron separation energies as
well as nucleon pairing-gap energies each with nuclear collectivity have been observed and
thoroughly discussed. Motivation for further studies of these correlations, as well as future
perspectives of in-ring mass measurements worldwide are outlined.
