相关论文: Description of resonant states in the shell model
Using the one-dimensional potential well with realistic parameters for atomic nuclei, we illustrate the movement of the poles of the S-matrix, and the transmission coefficient when the well supports an anti-bound state. We calculate the…
The physics of radioactive ion beams implies the description of weakly-bound nuclear systems. One key aspect concerns the coupling to low-lying collective-type excited states, which for these systems might not be stable levels, but particle…
Scattering on the energy shell is viewed here as the relation between the bound states of the Hamiltonian, restricted to sections on leads that are asymptotically independent, far away from the interaction region. The decomposition is…
The treatment of nuclear effects in neutrino-nucleus interactions is one of the main sources of systematic uncertainty for the analysis and interpretation of data of neutrino oscillation experiments. Neutrinos interact with nuclei via…
The molecular algebraic model based on three and four alpha clusters is used to describe the inelastic scattering of alpha particles populating low-lying states in $^{12}$C and $^{16}$O. Optical potentials and inelastic formfactors are…
A brief review of models to describe nuclear structure and reactions properties is presented, starting from the historical shell model picture and encompassing modern ab initio approaches. A selection of recent theoretical results on…
The $^{4}$He nucleus is a well bound and highly correlated four-nucleon system that is also found in form of $\alpha$-clusters as substructure in nuclear many-body systems. The standard single-particle shell model cannot represent these…
In the one nucleon sector of Nelson's massless model with an ultraviolet cut-off and no infrared regularization, one particle improper states are constructed and a scattering theory is developed both for the massless scalar field and for…
Fully-microscopic No-core Shell Model (NCSM) calculations of all stable $s$ and $p$ shell nuclei are used to determine realistic $NN$ interaction JISP16 describing not only the two-nucleon data but the binding energies and spectra of nuclei…
The generator coordinate method of a microscopic cluster model is developed to treat the resonance and scattering of nuclear clusters with complex scaling. We consistently derive the formulation of the complex scaling for the microscopic…
We investigate the degree of $\alpha$ ($^4$He nucleus) clustering in the ground-state density profiles of $^{44}$Ti and $^{52}$Ti. Two types of density distributions, shell- and cluster-model configurations, are generated fully…
We evaluate the allowed $\beta^-$-decay properties of nuclei with $Z = 8 - 15$ systematically under the framework of the nuclear shell model with the use of the valence space Hamiltonians derived from modern $ab~intio$ methods, such as…
We describe a new phenomenon in models of coalescence and fragmentation, that of gel-shatter cycles. These are dynamical, unforced, stochastic cycles in which slow, approximately deterministic coalescence up to and beyond gelation is…
Results are presented for the elastic scattering of electrons and protons from the exotic He and Li isotopes. Comparison with scattering results from the stable He and Li nuclei allows for an investigation into the effects that the…
Structural phenomena in nuclei, from shell structure and clustering to superfluidity and collective rotations and vibrations, reflect emergent degrees of freedom. Ab initio theory describes nuclei directly from a fully microscopic…
Nuclear clustering describes the appearance of structures resembling smaller nuclei such as alpha particles (4He nuclei) within the interior of a larger nucleus. While clustering is important for several well-known examples, much remains to…
We analyze the peculiarities of the interaction of the lambda hyperon with s-shell nuclei. The spectra of bound and scattering states are studied in the hypernuclei $_{\Lambda}^{2}$H, $_{\Lambda}^{3}$H, $_{\Lambda}^{4}$H, $_{\Lambda}^{4}$He…
Compound resonances in nucleon-nucleus scattering are related to the discrete spectrum of the target. Such resonances can be studied in a unified and general framework by a scattering model that uses sturmian expansions of postulated…
We review the recent progress in modelling neutrino-nucleus scattering, in a framework based on scaling which describes simultaneously the nuclear response to electromagnetic and weak probes. The study is relevant for the analysis of…
The neutron rich exotic unbound 7He nucleus has been the subject of many experimental investigations. While the ground-state 3/2- resonance is well established, there is a controversy concerning the excited 1/2- resonance reported in some…