First Observation of Unbound 11O, the Mirror of the Halo Nucleus 11Li
Abstract
The structure of the extremely proton-rich nucleus O1183 , the mirror of the two-neutron halo nucleus Li1138 , has been studied experimentally for the first time. Following two-neutron knockout reactions with a 13O beam, the 11O decay products were detected after two-proton emission and used to construct an invariant-mass spectrum. A broad peak of width ∼3.4 MeV was observed. Within the Gamow coupled-channel approach, it was concluded that this peak is a multiplet with contributions from the four lowest 11O resonant states: Jπ=3 /21- , 3 /22-, 5 /21+, and 5 /22+. The widths and configurations of these states show strong, nonmonotonic dependencies on the depth of the p - 9C potential. This unusual behavior is due to the presence of a broad threshold resonant state in 10N, which is an analog of the virtual state in 10Li in the presence of the Coulomb potential. After optimizing the model to the data, only a moderate isospin asymmetry between ground states of 11O and 11Li was found.
- Publication:
-
Physical Review Letters
- Pub Date:
- March 2019
- DOI:
- 10.1103/PhysRevLett.122.122501
- arXiv:
- arXiv:1812.08880
- Bibcode:
- 2019PhRvL.122l2501W
- Keywords:
-
- Nuclear Experiment;
- Nuclear Theory
- E-Print:
- 6 pages, three figures