The excitation function for production of 262Bh in the odd-Z-projectile reaction 208Pb(55Mn,n) has been measured at three projectile energies using the Berkeley Gas-filled Separator at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. In total, 33 decay chains originating from 262Bh and 2 decay chains originating from 261Bh were observed. The measured decay properties are in good agreement with previous reports. The maximum cross section of 540 +180 -150 pb is observed at a lab-frame center-of-target energy of 264.0 MeV and is more than fives times larger than that expected based on previously reported results for production of 262Bh in the analogous even-Z-projectile reaction 209Bi(54Cr,n). Our results indicate that the optimum beam energy in one-neutron-out heavy-ion fusion reactions can be estimated simply using the "Optimum Energy Rule" proposed by Swiatecki, Siwek-Wilczynska, and Wilczynski.

New isotope, 264Sg, was identified using the 38U(30Si,xn)268-xSg reaction and excitation functions for 262-264Sg were measured. 264Sg decays by spontaneous fission with a half life of 37 +27/-11 ms. The spontaneous fission branch for 0.9-s 263Sg was measured for the first time and found to be (13+-8) percent. 262Sg decays by spontaneous fission with a 15 +5/-3 ms half-life. Spontaneous fission partial half-life systematics are evaluated for even-even Sg isotopes from 258Sg through 266Sg, spanning the transition region between the N=152, Z=100 and N=162, Z=108 deformed shells.

This article starts with a review of the current SISAK liquid-liquid extraction system, as used after the physical preseparator BGS at LBNL for chemical studies of transactinide elements. Emphasis will be on new additions and developments. Then the possibilities offered by the new TASCA separator at GSI and the use of actinide targets at both GSI and LBNL are discussed with respect to future SISAK transactinide experiments. Finally, current and future liquid-liquid extraction systems for studying elements Rf up to Hs are discussed.