Probing Optimal Reaction Energy for Synthesis of Element 119 from ⁵¹V+²⁴⁸Cm Reaction with Quasielastic Barrier Distribution Measurement

International audienceThe quasielastic barrier distribution of 51V+248Cm was extracted by measuring the excitation function of quasielastic backscattering using a gas-filled recoil ion separator, GARIS-III. The obtained barrier distribution is well explained by the coupled-channels calculation, indicating a significant effect of the rotational excitation of deformed 248Cm. From the measured average Coulomb barrier height and deformation parameters of 248Cm, the side-collision energy leading to a compact configuration of colliding nuclei was obtained. The relation between the side collision energy and the excitation function of the evaporation-residue cross sections in the 48Ca+248Cm system was evaluated as a reference for the 51V+248Cm case. The optimal reaction energy to synthesize a new element 119 at the 51V+248Cm fusion reaction (3n and 4n channels) was estimated with an aid of these experimental data

Beta-strength and anti-neutrino spectra from total absorption spectroscopy of a decay chain 142

Beta decays of mass A = 142 isobaric chain starting from 142Cs have been investigated by means of Modular Total Absorption Spectrometer (MTAS) and on-line mass separation at Oak Ridge National Laboratory. The beta strength distribution derived for 142Cs decay from MTAS spectra is showing significant differences in β-feeding pattern when compared to the values listed at nuclear databases. MTAS results are shifting the associated anti-neutrino energy spectrum towards lower energies. A decay pattern deduced for 142Ba is similar to earlier reported results