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The unbound nucleus ^{26}O has been investigated using invariant-mass spectroscopy following one-proton removal reaction from a ^{27}F beam at 201  MeV/nucleon. The decay products, ^{24}O and two neutrons, were detected in coincidence using the newly commissioned SAMURAI spectrometer at the RIKEN Radioactive Isotope Beam Factory. The ^{26}O ground-state resonance was found to lie only 18±3(stat)±4(syst)  keV above threshold. In addition, a higher lying level, which is most likely the first 2^{+} state, was observed for the first time at 1.28_{-0.08}^{+0.11}  MeV above threshold. Comparison with theoretical predictions suggests that three-nucleon forces, pf-shell intruder configurations, and the continuum are key elements to understanding the structure of the most neutron-rich oxygen isotopes beyond the drip line.

Population-based screening for heart disease in this age range is limited by various factors. To analyze the mechanisms of sudden death in adolescents, we, therefore, are in need of a nationwide registry that includes autopsies for all deadly events.

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The heaviest bound isotope of boron 19 B has been investigated using exclusive measurements of its Coulomb dissociation, into 17 B and two neutrons, in collisions with Pb at 220 MeV=nucleon. Enhanced electric dipole (E1) strength is observed just above the two-neutron decay threshold with an integrated E1 strength of BðE1Þ ¼ 1.64 AE 0.06ðstatÞ AE 0.12ðsysÞ e 2 fm 2 for relative energies below 6 MeV. This feature, known as a soft E1 excitation, provides the first firm evidence that 19 B has a prominent two-neutron halo. Three-body calculations that reproduce the energy spectrum indicate that the valence neutrons have a significant s-wave configuration and exhibit a dineutronlike correlation.