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Two excited J(pi)=0(+) states in Pb-186 populated in the a-decay of Po-190 have been identified through alpha -particle/conversion electron coincidences in an experiment at the velocity filter SHIP ...

The production cross sections were measured for the xn, pxn, and αxn de-excitation channels of the 212Rn compound nuclei formed at excitation energies of 80–160 MeV in the reaction 22Ne + 190Os. The maximum cross sections obtained for the xn (x = 8–12), pxn (x = 8–11) and αxn (x = 8–11) reaction channels were fitted satisfactorily with the computer code HIVAP using its standard parameter set except that the single scaling parameter C = 0.65 was implemented to adjust the values of the liquid-drop fission barriers predicted by the Cohen-Plasil-Swiatecki (CPS) model. Additionally, an analysis of a large set of data on the formation cross sections of neutron-deficient Z = 83–92 nuclei showed that the whole body of data obtained for the nuclear region notable for the large variations of both the liquid-drop barrier and the shell effects, can be described well with practically the same parameter C = 0.55–0.68. One may take this observation as an indication that, though the CPS model overestimates the liquid-drop fission barriers, it reproduces well the relative behaviour of these barriers in the whole range of neutron-deficient Z = 83–92 nuclei.

Heavy-ion fusion reaction ER's were studied in a wide excitation energy range of the 199,193,191 Bi and 217 Ac compound nuclei produced with bombarding ions of 40 Ar , 40 Ca and 20 Nc . The problems of the shell effect fading with increasing nucleus excitation energy and the isospin dependence of the macroscopic component of the fission barrier are discussed.