Study of the complete-fusion reaction 226Ra+48Ca

The results of the experiment aimed at the synthesis of 108 isotopes in the 226Ra(48Ca,xn)274-xHs nuclear reaction are presented. The experiment was performed using the Dubna gas-filled recoil separator at the U400 cyclotron. We observed six genetically linked decay chains of the parent 270Hs nuclei. The properties of this isotope decaying by α-emission with Qα=9.02±0.08 MeV and T1/2=7.6 s to the 266Sg, which undergoes spontaneous fission (T1/2=0.28 s), are compared with the properties of the same isotope produced earlier in the reaction 248Cm(26Mg,3-5n)269-271Hs [1]. The values of the measured cross-sections of the reactions with evaporation of 3 to 5 neutrons are discussed. The obtained experimental results allow us to estimate the probability of nuclear fusion for the heavier particle-projectile combinations, e.g., with the 50Ti projectiles. One could expect that production cross sections of the reactions of 243Am+50Ti and 249Cf+50Ti that lead to the new elements 117 and 120 could exceed 0.2 pb [2].(author)