SPONTANEOUS FISSION PROPERTIES OF (262)(104)RF

We have measured the mass and kinetic-energy distributions of fragment s from the spontaneous fission (SF) of (262)(104)Rf. The (262)(104)Rf was produced via the Pu-244(Ne-22,4n) reaction with a production cross section of similar to 0.7 nb using 114.4-MeV projectiles. The kinetic energies and times of the coincident fission fragments were measured using our rotating wheel system. From these data the half-life, mass, and kinetic-energy distributions were derived. The total kinetic-energ y (TKE) distribution appears to consist of a single component with a m ost probable pre-neutron-emission TKE of 215+/-2 MeV. The mass distrib ution is symmetric with a full width at half maximum of about 22 mass numbers. These results are consistent with trends observed for other t rans-berkelium spontaneously fissioning isotopes. We determined the ha lf-life to be 2.1+/-0.2 s by measuring its spontaneous fission decay. We also attempted to observe the alpha decay of (262)(104)Rf by search ing for alpha decay correlated in time with SF from the alpha daughter , 1.2-ms No-258. We observed no such decays and have set an upper limi t of 0.8% (68% confidence level) on the alpha decay branch of (262)(10 4)Rf.