R&D status of pulse shape analysis for short-lived decay of superheavy elements in GARIS-II

  • S. Yamaki
  • K. Morimoto
  • D. Kaji
  • Ya. Wakabayashi
  • M. Takeyama
  • K. Tanaka
  • T. Tanaka
  • H. Baba
  • H. Yamaguchi
  • T. Suzuki
  • K. Morita


To search undiscovered superheavy elements, a series of commissioning experiments for the new gas-filled separator GARIS-II at RIKEN was recently carried out. A new data acquisition method was tested to study the short-lived α decay. Both the α decay and evaporation residues were detected by the silicon detectors, and the preamplified waveforms were then directly registered by a flash ADC and analyzed by means of a pulse shape analysis. This paper describes the identification of two sequential pulses (pileup events) from short-lived α decays and the determination of their energy and time difference by the template fitting method. The performance of the present system was evaluated by using a simulated data set and was successfully employed for online experimental data such as 220Ac → 216Fr. 


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How to Cite
YAMAKI, S. et al. R&D status of pulse shape analysis for short-lived decay of superheavy elements in GARIS-II. Physical Sciences and Technology, [S.l.], v. 3, n. 1, p. 12-16, mar. 2017. ISSN 2409-6121. Available at: <http://phst.kaznu.kz/index.php/journal/article/view/88>. Date accessed: 19 mar. 2019. doi: https://doi.org/10.26577/phst-2016-1-88.
Nuclear Physics and Related Techology


Superheavy elements, Pulse-shape analysis, α decays, short half-life