Proton number, Z, and mass number,A, assignments for newly discovered heavy element nuclides have historically been made by observing decay to a daughter with well-established Z and A, and then observing the well-know decay of that daughter. For all of the new superheavy element isotopes observed in 48 Ca irradiations of actinide targets, this correlation technique has not been possible, because the -decay chains end in spontaneous fission of previously unknown isotopes. Consequently, Z and A

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... signments have been made by less-direct means. The superheavy element Z and A assignment methods are summarized, and possibilities for how they may be incorrect are explored. While it is highly likely that most of the superheavy element Z and A assignments are correct, there is a real need for a direct proof. a