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arXiv · 1503.06191

Three-body correlations in the ground-state decay of 26O

Z. Kohley·T. Baumann·G. Christian·P. A. DeYoung·J. E. Finck·N. Frank·B. Luther·E. Lunderberg·M. Jones·S. Mosby·J. K. Smith·A. Spyrou·M. Thoennessen
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Abstract

Background: Theoretical calculations have shown that the energy and angular correlations in the three-body decay of the two-neutron unbound O26 can provide information on the ground-state wave function, which has been predicted to have a dineutron configuration and 2n halo structure. Purpose: To use the experimentally measured three-body correlations to gain insight into the properties of O26, including the decay mechanism and ground-state resonance energy. Method: O26 was produced in a one-proton knockout reaction from F27 and the O24+n+n decay products were measured using the MoNA-Sweeper setup. The three-body correlations from the O26 ground-state resonance decay were extracted. The experimental results were compared to Monte Carlo simulations in which the resonance energy and decay mechanism were varied. Results: The measured three-body correlations were well reproduced by the Monte Carlo simulations but were not sensitive to the decay mechanism due to the experimental resolutions. However, the three-body correlations were found to be sensitive to the resonance energy of O26. A 1σ upper limit of 53 keV was extracted for the ground-state resonance energy of O26. Conclusions: Future attempts to measure the three-body correlations from the ground-state decay of O26 will be very challenging due to the need for a precise measurement of the O24 momentum at the reaction point in the target.

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Z. Kohley, T. Baumann, G. Christian, P. A. DeYoung, J. E. Finck, N. Frank, B. Luther, E. Lunderberg, M. Jones, S. Mosby, J. K. Smith, A. Spyrou, M. Thoennessen. 2015-03-20. Three-body correlations in the ground-state decay of 26O. https://doi.org/10.1103/physrevc.91.034323

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