Measurements of cross sections for the fusion-evaporation reactions 244Pu(48Ca,xn)292-x114 and 245Cm(48Ca,xn)293-x116

Abstract

We have studied the excitation functions of the reactions 244Pu(48Ca,xn). Maximum cross sections for the evaporation of 3-5 neutrons in the complete-fusion reaction 244Pu+ 48Ca were measured to be (σ3n=2 pb, σ4n = 5 pb, and σ5n= 1 pb. The decay properties of 3n-evaporation product 289114, in the decay chains observed at low 48Ca energy coincide well with those previously observed in the 244Pu+48Ca and 248Cm+ 48Ca reactions and assigned to 288114. Two isotopes of element 114 and their descendant nuclei were identified for the first time at higher bombarding energies: 288114 (Eα= 9.95 MeV, T1/2=0.6 s) and 287114 (Eα=10.04 MeV, T1/2 = 1 s). We also report on the observation of new isotopes of element 116, 290,291116, produced in the 245Cm+ 48Ca reaction with cross sections of about 1 pb. A discussion of self-consistent interpretations of all observed decay chains originating at Z=118, 116, and 114 is presented.