Ponente
Descripción
In this contribution, the preliminary results obtained from implantation in Active Stopper during an experiment scheduled in June 2024 will be presented . This experiment is a part of the DESPEC collaboration at the GSI-FAIR Phase-0 campaign.The experiment focuses on exploring the region beyond N = 126 shell closure, which is relevant to the modeling of the r-process as most nuclei in this region are formed by this process.
In the experiment, a 238U beam accelerated to 1 GeV/nucleon is directed on a 9Be target to produce heavy neutron rich nuclei by cold fragmentation reaction.The Fragment Separator (FRS) is used to separate the exotic nuclei by in-flight technique. These separated ions are then implanted in AIDA active stopper which consists of two triple-wafer DSSDs. The AIDA setup is placed between two plastic scintillators to measure the timing of the implanted ions. A DINTESPEC detector consisting of three DSSDs is positioned behind AIDA. The hybrid FATIMA + DEGAS array, consisting of 36 LaBr3 and 27 HPGe detectors has been used to extract γ decay and lifetime information.
We have observed α decays from implants in the Active Stopper during our experiment and conducted some preliminary studies to characterize these decays. α spectra for the X strips in DSSD0 have been obtained with α energy aligned according to the ground-state α decay of 215Po. Using an α-γ correlation analysis within a prompt time-coincidence window of approximately 4 μs, we can successfully identify some peaks in the α spectra. Additionally, an α-tagged β delayed γ spectroscopy study was performed to investigate the α decays with very short half-lives. The findings of these studies, including the identification of specific α decays through this methodology will be presented in this contribution.
