Rimantas Lazauskas

Testing nonlocal nucleon-nucleon interactions in four-nucleon systems

The Faddeev-Yakubovski equations are solved in configuration space for the {alpha}-particle and n-{sup 3}H continuum states. We test the ability of nonlocal nucleon-nucleon interaction models to describe 3N and 4N systems.

Description of He 4 tetramer bound and scattering states

Faddeev-Yakubovski equations are solved numerically for

Nuclear electric dipole moment of three-body systems

^{4}\mathrm{He}

Application of complex-scaling method for few-body scattering

tetramer and trimer states using realistic helium-helium interaction models. We describe the properties of ground and excited states, and we discuss with a special emphasis the

A new vibrational level of the H2+ molecular ion

^{4}\mathrm{He}\text{\ensuremath{-}}^{4}\mathrm{He}_{3}

Up to N{sup 3}LO heavy-baryon chiral perturbation theory calculation for the M1 properties of three-nucleon systems

low energy scattering.

Three-neutron resonance trajectories for realistic interaction models

Nuclear electric dipole moments of 3 He and 3 H are calculated using Time Reversal Invariance Violating (TRIV) potentials based on the meson exchange theory, as well as the ones derived by using pionless and pionful effective field theories, with nuclear wave functions obtained by solving Faddeev equations in configuration space for the complete Hamiltonians comprising both TRIV and realistic strong interactions. The obtained results are compared with the previous calculations of 3 He EDM and with time reversal invariance violating effects in neutron-deuteron scattering.

Critical temperature for {alpha}-particle condensation within a momentum-projected mean-field approach

A formalism based on the complex-scaling method is developed for solving the few-particle scattering problem, in terms of bound state boundary conditions. Several applications are presented to demonstrate the efficiency of the method for computing the elastic and three-body breakup reactions in systems described by Hamiltonians which may include both short- and long-range interactions.

An ``archaeological'' quest for galactic supernova neutrinos

A new vibrational level of the H2+ molecular ion with binding energy of 1.09 × 10−9 a.u. ≈ 30 neV below the first dissociation limit is predicted, using highly accurate numerical non-relativistic quantum calculations, which go beyond the Born-Oppenheimer approximation. It is the first-excited vibrational level v = 1 of the 2pσu electronic state, antisymmetric with respect to the exchange of the two protons, with orbital angular momentum L = 0. It manifests itself as a huge p-H scattering length of a = 750 ± 5 Bohr radii.

Search for new physics with neutrinos at Radioactive Ion Beam facilities

M1 properties, comprising magnetic moments and radiative capture of thermal neutron observables, are studied in two- and three-nucleon systems. We use meson exchange current derived up to N{sup 3}LO using heavy baryon chiral perturbation theory a la Weinberg. Calculations have been performed for several qualitatively different realistic nuclear Hamiltonians, which permits us to analyze model dependence of our results. Our results are found to be strongly correlated with the effective range parameters such as binding energies and the scattering lengths. Taking into account such correlations, the results are in good agreement with the experimental data with small model dependence.