8,671 research outputs found
Coupled-channel calculation of bound and resonant spectra of Lambda-9Be and Lambda-13C hypernuclei
A Multi-Channel Algebraic Scattering (MCAS) approach has been used to analyze
the spectra of two hyper-nuclear systems, Lambda-9Be and Lambda-13C. The
splitting of the two odd-parity excited levels (1/2^- and 3/2^-) at 11 MeV
excitation in Lambda-13C is driven mainly by the weak Lambda-nucleus spin-orbit
force, but the splittings of the 3/2^+ and 5/2^+ levels in both Lambda-9Be and
Lambda-13C have a different origin. These cases appear to be dominated by
coupling to the collective 2+ states of the core nuclei. Using simple
phenomenological potentials as input to the MCAS method, the observed splitting
and level ordering in Lambda-9Be is reproduced with the addition of a weak
spin-spin interaction acting between the hyperon and the spin of the excited
target. With no such spin-spin interaction, the level ordering in Lambda-9Be is
inverted with respect to that currently observed. In both hyper-nuclei, our
calculations suggest that there are additional low-lying resonant states in the
Lambda-nucleus continua.Comment: 15 pages, 3 figures, 6 tables. To be published in International
Journal of Modern Physics
Exploring abstinence, recovery, identity and personhood in individuals engaging with addiction services
Section A: This review aimed to understand how abstinence is understood in recovery by those who access substance misuse services. A systematic literature review was undertaken
and fourteen studies were identified. These were quality assessed using the CASP quality analysis tool. Limitations of CASP as a tool were discussed. The fourteen studies were
analysed using thematic synthesis and seven themes with ten sub-themes were identified. Themes were organised along a temporal path. Future clinical and research directions were
discussed, as were strengths and limitations of the paper.
Section A: This review aimed to understand how abstinence is understood in recovery by those who access substance misuse services. A systematic literature review was undertaken
and fourteen studies were identified. These were quality assessed using the CASP quality analysis tool. Limitations of CASP as a tool were discussed. The fourteen studies were
analysed using thematic synthesis and seven themes with ten sub-themes were identified. Themes were organised along a temporal path. Future clinical and research directions were
discussed, as were strengths and limitations of the paper
Collective-coupling analysis of spectra of mass-7 isobars: ^7He, ^7Li, ^7Be, ^7B
A nucleon-nucleus interaction model has been applied to ascertain the
underlying character of the negative-parity spectra of four isobars of mass
seven, from neutron-- to proton--emitter driplines. With one single nuclear
potential defined by a simple coupled-channel model, a multichannel algebraic
scattering approach (MCAS) has been used to determine the bound and resonant
spectra of the four nuclides, of which ^7He and ^7B are particle unstable.
Incorporation of Pauli blocking in the model enables a description of all known
spin-parity states of the mass-7 isobars. We have also obtained spectra of
similar quality by using a large space no-core shell model. Additionally, we
have studied ^7Li and ^7Be using a dicluster model. We have found a
dicluster-model potential that can reproduce the lowest four states of the two
nuclei, as well as the relevant low-energy elastic scattering cross sections.
But, with this model, the rest of the energy spectra cannot be obtained.Comment: Extended version published in Phys. Rev. C, 16 pages and 5 figure
Non-localities in nucleon-nucleus potentials
Two causes of non-locality inherent in nucleon-nucleus scattering are
considered. They are the results of two-nucleon antisymmetry of the projectile
with each nucleon in the nucleus and the dynamic polarization potential
representation of channel coupling. For energies MeV, a
g-folding model of the optical potential is used to show the influence of the
knock-out process that is a result of the two-nucleon antisymmetry. To explore
the dynamic polarization potential caused by channel coupling, a multichannel
algebraic scattering model has been used for low-energy scattering.Comment: 12 pages, 11 figures, submitted to EPJ
Modeling, Analysis, and Optimization Issues for Large Space Structures
Topics concerning the modeling, analysis, and optimization of large space structures are discussed including structure-control interaction, structural and structural dynamics modeling, thermal analysis, testing, and design
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