Experiments on synthesis of the heaviest elements at RIKEN K. Morimoto Nishina Center for Accelerator Based Science RIKEN (The Institute of Physical and Chemical Research), Japan In the Institute of Physical and Chemical Research (RIKEN), using high intensity heavy ion beams from RIKEN Linear Accelerator, productions and decays of isotopes of the heaviest elements have been investigated by using a gas-filled recoil separator, GARIS. The isotopes studied were 208 58 Pb( Fe, n), 208 265 Hs, 64 271 Pb( Ni, n), Ds, 209 272 Rg, 277 112, and 64 Bi( Ni, n), 277 112), and 2 ( 113, produced by reactions 208 70 209 Pb( Zn, n), respectively. The numbers of atoms observed were 10 ( ( 278 265 Hs), 14 ( 70 Bi( Zn, n), 271 Ds), 14 ( 272 Rg), 2 278 113). Based on the observed decay chains consisted of consecutive alpha decays connected to the previously known alpha decays or spontaneous fissions, assignments of the initially produced isotopes were done. Our data with the atomic number from 108 to 112, agree well with the data previously taken. The production cross section of the isotope 278 113 of the 113th element have leached around 30 fb which shows simple decrease of the cross section with the increase of the atomic number. The isotopes were produced, for the first time in the 1n evaporation channel from heavy-ion induced complete fusion reaction. References  K. Morita et al., Eur. Phys. J. A21, 257 (2004).  K. Morita et al., J. Phys. Soc. Jpn. 73, 1738 (2004).  K. Morita et al., J. Phys. Soc. Jpn. 73, 2593 (2004).