Low-lying T = 0 levels of 16O are described by a microscopic 12C + α cluster-coupling model, in which the states (0+, 2+, 4+) ground band coupled with relative motion between and α. The equation for two clusters is solved taking into account Pauli principle. Calculated energy spectra good agreement experiment. mysterious zero plus state successfully understood present model. A characteristic feature wave functions shows up weak coupling spin orbital angular momentum. Some predictions made on...

We systematically study total reaction cross sections of carbon isotopes with $N=6\text{\ensuremath{-}}16$ on a proton target for wide range incident energies. An emphasis is put the difference from case target. The calculations include $^{19,20,22}\mathrm{C}$ at $40A$ MeV, data which have recently been measured RIKEN. Glauber theory used to calculate sections. To describe intrinsic structure isotopes, we use Slater determinant generated phenomenological mean-field potential, and construct...

Variational calculations for $s$-shell hypernuclei are performed by explicitly including $\ensuremath{\Sigma}$ degrees of freedom. Four sets $YN$ interactions [SC97d(S), SC97e(S), SC97f(S), and SC89(S)] used. The bound-state solution $_{\mathrm{\ensuremath{\Lambda}}}^{\mathrm{5}}\mathrm{H}\mathrm{e}$ is obtained a large energy expectation value the tensor $\ensuremath{\Lambda}N\mathrm{\text{\ensuremath{-}}}\ensuremath{\Sigma}N$ transition part found. internal...

The positronium molecule $({\mathrm{Ps}}_{2})$ has not been experimentally observed yet because its tiny (4.5 eV) binding energy cannot be detected when the annihilates by emitting two photons with of 0.51 MeV each. It is shown in this paper that electric dipole transition between recently found $L=1$ excited state and $L=0$ ground characteristic photon 4.94 eV a clear signature existence possibility experimental observation realistic. probability about 17% total decay rate. Another Coulomb...

A systematic analysis is made on the total reaction cross sections for Ne, Mg, Si, and S isotopes. The high-energy nucleus-nucleus collision described based Glauber model. Using Skyrme-Hartree-Fock method in three-dimensional grid-space representation, we determine nuclear density distribution a wide range of nuclei self-consistently without assuming any spatial symmetry. calculated consistently agree with recent section data Ne${+}^{12}$C at 240 $A$MeV, which makes it possible to discuss...

A new, hitherto unknown bound state of the positronium molecule, with orbital angular momentum $L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$ and negative parity, is reported. This stable against autodissociation even if masses positive charges are not equal. The existence a similar in two dimensions has also been investigated. fact that biexcitons have second may aid better understanding their binding mechanism.

The binding energies and other properties of the excitonic complexes (bound systems electrons holes) in two three dimensions (2D 3D) are calculated by a precise variational method. mass ratios for limit stability ${X}_{3}^{+}(\mathrm{eehhh})$ determined both 2D 3D cases. Two excited states biexciton found to remain bound any ratio.

The elastic breakup of a three-body projectile on target is studied within the eikonal approximation with full account final-state interactions. Bound and scattering states are calculated in hyperspherical coordinates Lagrange mesh. A correction introduced to avoid divergence cross sections due Coulomb interaction. allows direct calculation various sections, particular multidifferential can be obtained. model applied $^{6}\mathrm{He}$ $^{208}\mathrm{Pb}$. halo nucleus described...

Baryon-baryon interactions for the complete baryon octet ${(B}_{8})$ are investigated in a unified framework of resonating-group method, which spin-flavor ${\mathrm{SU}}_{6}$ quark-model wave functions employed. Model parameters determined to reproduce properties nucleon-nucleon system and low-energy cross section data hyperon-nucleon interaction. We then proceed explore ${B}_{8}{B}_{8}$ strangeness $S=\ensuremath{-}2,$ $\ensuremath{-}3,$ $\ensuremath{-}4$ sectors. The S-wave phase-shift...

The spectra of quantum dots different geometries (quantum ring, cylinder, spherical square well, and parabolic) are studied. stochastic variational method on correlated Gaussian basis functions a large scale shell-model approach have been used to investigate these ``artificial'' atoms their properties in magnetic fields. Accurate numerical results presented for $N=2--8$ electron systems.

A formulation is presented for a variational calculation of N-body systems on correlated Gaussian basis with arbitrary angular momenta. The rotational motion the system described single spherical harmonic total momentum L, and thereby needs no explicit coupling partial waves between particles. simple generating function exploited to derive matrix elements. applied various Coulomb three-body such as , up L = 4 in order show its usefulness versatility. stochastic selection functions yields...

A precise description of neutrino-nucleus reactions will play a key role in addressing fundamental questions such as the leptonic CP violation and neutrino mass hierarchy through analyzing data from next-generation oscillation experiments. The energy relevant to spans broad range and, accordingly, dominant reaction mechanism varies across region quasi-elastic scattering nucleon resonance excitations deep inelastic scattering. This corresponds transitions effective degree freedom for...

The energy and the width of resonance states are determined by analytic continuation bound-state energies as a function coupling constant (potential strength). advantage method is that existing techniques for calculation bound can be applied, without any modifications, to determine position resonances. Various numerical examples show applicability three-body systems, including excited ${}^{6}$He ${}^{6}$Li.

Resonances of electron-positron complexes are studied by the stochastic variational method combined with complex scaling method. Several low-lying resonances in positronium negative ion obtained. One P-state and nine S-state molecule predicted below $\mathrm{Ps}(n=1)+\mathrm{Ps}(n=4)$ threshold. The structure some these is analyzed.

The 6He β decay into α and deuteron is studied with different simple models a semi-microscopic model based on variational microscopic wave functions expanded in three-center harmonic-oscillator basis. latter approach allows us to show that this quenched by cancellation between the internal halo contributions Gamow-Teller matrix element. An extreme sensitivity description up distances as large 15 fm observed. Contrary several available effective forces, Volkov force V2 reproduces measured...

The breakup of a one-neutron halo nucleus is studied in the eikonal approximation. Both nuclear and Coulomb processes are taken into account. continuum states, which usually approximated by plane waves, constrained to satisfy condition orthogonality bound states nucleus. Taking full account recoil effect, neutron-core relative energy distributio no f cross section calculated for 11 Be 19 C projectiles incident on 12 Ca nd 208 Pb targets compared experimental data. All data regarding...