On the production of superheavy elements

Since the discovery of Deformed Superheavy Nuclei (1983 - 85) a bridge connects the island of SHE to known isotopes of lighter elements. What we know experimentally and theoretically on the nuclear structure of SHE is reported in a first section. The making of the elements with an analysis of production cross sections and its macroscopic limitation to Z = 112 + #epsilon# is presented in a second section. The break-down of fusion cross sections in the ''Coulomb Falls'' within a range of about 10 elements is introduced as the universal limiting phenomenon. How the nuclear structure of the collision partners modifies the on-set of this limitation is presented in section 3. Reactions induced by deformed nuclei are pushed by side collisions to higher excitation energies (4n-and 5n-channels), whereas reactions driven by the cluster-like, closed-shell nuclei, "2"0"8_1_2_6Pb and "1"3"8_8_2Ba, are kept at low excitation energies (1n- and 2n-channels). The on-set of production limitation for deformed collision partners is moved to smaller effective fissilities x = 0.68 #<=# 0.72, whereas for spherical clusters the onset is delayed x= 0.76 #>=# 0.72 and x 0.79 #>=# 0.72 for "1"3"8Ba and "2"0"8Pb, respectively. An outlook, what remains to be done in the future, ends the article. (orig.)Published in: C.R. Acad. Sci., Paris (FR), Serie IV (2003)Available from TIB Hannover: RO 801(03-12) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman