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Intermediate energy single-neutron removal from 31Mg has been employed to investigate the transition into the N=20 island of inversion. Levels up to 5 MeV excitation energy in 30Mg were populated and spin-parity assignments were inferred from the corresponding longitudinal momentum distributions and γ-ray decay scheme. Comparison with eikonal-model calculations also permitted spectroscopic factors to be deduced. Surprisingly, the 02+ level in 30Mg was found to have a strength much weaker than expected in the conventional picture of a predominantly 2p−2h intruder configuration having a large overlap with the deformed 31Mg ground state. In addition, negative parity levels were identified for the first time in 30Mg, one of which is located at low excitation energy. The results are discussed in the light of shell-model calculations employing two newly developed approaches with markedly different descriptions of the structure of 30Mg. It is concluded that the cross-shell effects in the region of the island of inversion at Z=12 are considerably more complex than previously thought and that np−nh configurations play a major role in the structure of 30Mg.

Scattering of 8He from 4He has been performed through the coincident detection of the scattered particles using a silicon array within a helium-4 gas volume with a 8He beam. This permitted the reconstruction of the interaction probability as a function of position within the gas and hence the excitation function to be calculated together with the angular distribution of the products. These measurements also enabled the reconstruction of the two-neutron transfer to 6Heâ+â6He. The measurements provide the first characterisation of the scattering of the α+4n, 8He, halo nucleus from 4He and the 2n-transfer to populate the symmetric final state. The results indicate the presence of a L=4 component at excitation energies of 14â15 MeV, consistent with a broad (â¼1 MeV) JÏ=4+ resonance. These measurements would agree with generalized two-centre cluster model (GTCM) calculations indicating a cluster, or molecular, structure predicted at this energy. Keywords: Nuclear clustering, Molecular states, Light nuclei

Background: Causes of variations in outcomes from cancer care in developed countries are often unclear. Australia has developed health system pathways describing consensus standards of optimal cancer care across the phases of prevention through to follow-up or end-of-life. These Optimal Care Pathways (OCP) were introduced from 2013 to 14. We investigated whether care consistent with the OCP improved outcomes for colon cancer patients. Methods: Colon patients diagnosed from 2008 to 2014 were identified from the Australian State of Victoria Cancer Registry (VCR) and cases linked with State and Federal health datasets. Surrogate variables describe OCP alignment in our cohort, across three phases of the pathway; prevention, diagnosis and initial treatment and end-of-life. We assessed the impact of alignment on (1) stage of disease at diagnosis and (2) overall survival. Findings: Alignment with the prevention phase of the OCP occurred for 88% of 13,539 individuals and was associated with lower disease stage at diagnosis (OR = 0.33, 95% confidence interval 0.24 to 0.42), improved crude three-year survival (69.2% versus 62.2%; p