Spectroscopic Tools Applied to Flerovium Decay Chains

Abstract

An upgraded TASISpec setup, with the addition of a veto DSSD and the new Compex detector-germanium array, has been employed with the gas-filled recoil separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, to study flerovium (element 114) decay chains. The detector upgrades along with development of new analytical techniques have improved the sensitivity of the TASISpec setup for measuring α-photon coincidences. These improvements have been assessed with test reactions. The reaction 48Ca+206,207Pb was used for verification of experimental parameters such as transmission to implantation DSSD and target-segment to α-decay correlations. The reaction 48Ca+ nat Hf was used to produce several short-lived nuclei with multiple-α decay chains to investigate pile-up event deconvolution.

Results and plans for nuclear spectroscopy of superheavy nuclei: the Lund perspective

“…For the 'element 114 experiment', a more sophisticated study of a number of cases of implanted nuclei produced in preparatory experiments yielded r = r (Z 2 ) ≈ 0.40 − 0.60 for Z ≈ 85 − 115 [21,30]. Either way, the methods were tested on ample known α emitters in the range E α ≈ 7 − 12 MeV and found to agree with tabulated values within < 10 keV [20,21,29].…”

“…6.9 in [20] and Fig. 3 in [30]). Simulations -or virtual experiments -using the Geant4 toolkit have entered the nuclear physics domain some time ago.…”

“…Originally scheduled for summer 2018, it could first be conducted in two parts in 2019 and 2020, respectively, due to accelerator problems. Four out of five Compex modules were delivered and used, while the set-up was otherwise a fine-tuned version of TASISpec [30]. More details of the set-up, the experiment itself, and the specific analysis steps and tools are described comprehensively in [21].…”