Line-shape analysis of Doppler-broadened gamma lines following the beta decay of Li-11

C. M. Mattoon, F. Sarazin*, C. Andreoiu, A. N. Andreyev, R. A. E. Austin, G. C. Ball, R. S. Chakrawarthy, D. Cross, E. S. Cunningham, J. Daoud, P. E. Garrett, G. F. Grinyer, G. Hackman, D. Melconian, C. Morton, C. Pearson, J. J. Ressler, J. Schwarzenberg, M. B. Smith, C. E. Svensson

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

The beta decay of Li-11 is studied at the TRIUMF Isotope Separation and Acceleration (ISAC) facility using the 8 pi gamma-ray spectrometer coupled with an inner array of 20 plastic scintillators for beta detection. Doppler-broadened line shapes resulting from the decay of the excited states in Be-10 populated by beta-delayed one-neutron emission are analyzed using Monte Carlo simulations. New beta-delayed neutron decay branches are shown to contribute to the complex decay of Li-11. The half-lives of all but one bound excited state in Be-10 are also deduced from this work. Among them, the half-life of the 2(-) state in Be-10 is shown to be much shorter than previously thought, yielding a new experimental B(E1) now well within the range of theoretical predictions and providing further evidence that the 2(-) state in Be-10 is an excited halo state. The nature of the 8.82-MeV state in Be-11 and its decay paths to excited states in Be-10 are found to be consistent with the beta decay of the core proceeding through this particular state.

Original languageEnglish
Article numberARTN 034318
Number of pages13
JournalPhysical Review C
Volume80
Issue number3
DOIs
Publication statusPublished - 23 Sep 2009

Keywords

  • LIGHT-NUCLEI
  • SPECTROSCOPY
  • ENERGY-LEVELS
  • RADII
  • BE-11
  • POLARIZED LI-11
  • INTERACTION CROSS-SECTIONS
  • HALO STRUCTURE
  • 18 MEV STATE

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