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The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He reaction was found at about 2.1±0.2  MeV (Γ∼2  MeV) above the three-body ^{8}He+n+n breakup threshold. Angular correlations observed for ^{10}He decay products show prominent interference patterns allowing us to draw conclusions about the structure of low-energy excited states. We interpret the observed correlations as a coherent superposition of a broad 1- state having a maximum at energy 4-6 MeV and a 2+ state above 6 MeV, setting both on top of the 0+ state "tail." This anomalous level ordering indicates that the breakdown of the N=8 shell known in 12Be thus extends also to the ^{10}He system.

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Two-proton decay of the 17 Ne low-lying states populated in the 1 H( 18 Ne, d) 17 Ne transfer reaction was studied. The two-proton width Γ2p of the 17 Ne first excited 3/2 − state at E * = 1.288 MeV is of importance for the two-proton radioactivity theory and nuclear-astrophysics applications. A dedicated search for the two-proton emission of this state was performed leading to the new upper limit obtained for the width ratio Γ2p/Γγ < 1.6(3) × 10 −4 . A novel, "combined mass" method is suggested and tested capable to improve the resolution of the experiment which is a prime significance for the study of nuclear states with extremely small particle-to-gamma width ratios Γpart/Γγ . The condition Γpart ≪ Γγ is quite common for the states of astrophysical interest which makes the proposed approach promising in this field.