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The synthesis of superheavy elements beyond the oganesson (Og, Z = 118) remains one of the actual topics in nuclear physics. For this purpose, the fusion reactions with projectiles heavier than 48Ca, which were successfully implied for the synthesis of the heaviest elements, and actinide targets have to be used. However, empirical knowledge on such reactions is almost absent. In this work, the experimental cross sections of the "hot", "cold", and 48Ca+actinide reactions were analyzed to reveal their differences in the three steps of the fusion-evaporation process. The evaporation residue cross sections represented as a function of the mean fissility parameter show the hitherto unnoticed difference between the "hot" and "cold" fusion reactions, which is in agreement with nuclear reaction dynamic studies. Based on the newly suggested systematics, the evaporation residue cross sections for the 50Ti, 51V, 54Cr, 58Fe and 64Ni-induced reactions with actinide targets were estimated within the two different empirical approaches. [ABSTRACT FROM AUTHOR]

A question for decades has been the potential production of heavy or superheavy elements in nature. Once the nuclear weapons tests showed that elements heavier than the Uranium were found in the debris, it was clear that a rapid neutron capture process followed by beta decay was creating heavier elements. The next question was the location of the r-process end? What other heavy elements are made? Did nature make the superheavy elements via the r-process too? The answer is yet to be found. There are many indications that it probably did but the definitive evidence is yet to surface. The laboratory experiments with neutron rich beams and neutron rich targets via cold and hot fusion reactions have created a number of new isotopes in addition to the elements that have completed the periodic table. Furthermore, the new superheavy element factory at the JINR in Dubna has now allowed the identification of over one hundred decay chains of the various isotopes of superheavy elements connecting to the main part of the chart of nuclides via decays. This is where we should look for the definitive evidence for the production of the superheavy elements in nature. [ABSTRACT FROM AUTHOR]