A5074647073- Nuclear physics research studies
- Quantum Chromodynamics and Particle Interactions
- Advanced Chemical Physics Studies
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Quantum chaos and dynamical systems
- Advanced NMR Techniques and Applications
- Astronomical and nuclear sciences
- Inorganic Fluorides and Related Compounds
- Quantum, superfluid, helium dynamics
- Molecular spectroscopy and chirality
- Cold Atom Physics and Bose-Einstein Condensates
- Particle physics theoretical and experimental studies
- Superconducting Materials and Applications
- Rare-earth and actinide compounds
- Physics of Superconductivity and Magnetism
- Theoretical and Computational Physics
- Scientific Research and Discoveries
- Particle accelerators and beam dynamics
- Atomic and Subatomic Physics Research
- Molecular Spectroscopy and Structure
- High-pressure geophysics and materials
- Neutrino Physics Research
- Magnetic properties of thin films
- Mathematics and Applications
Centre National de la Recherche Scientifique
2006-2021
Université de Strasbourg
2005-2021
University of Padua
2016-2020
Institut Pluridisciplinaire Hubert Curien
2006-2019
Laboratoire de Physique Théorique
1986-2008
Universidad Autónoma de Madrid
1995-2008
Eurométropole de Strasbourg
2008
Institut National de Physique Nucléaire et de Physique des Particules
1994-2007
Institut Pasteur
2005
Institut de recherches économiques et sociales
2002-2003
The last decade has witnessed both quantitative and qualitative progress in shell-model studies, which have resulted remarkable gains our understanding of the structure nucleus. Indeed, it is now possible to diagonalize matrices determinantal spaces dimensionality up ${10}^{9}$ using Lanczos tridiagonal construction, whose formal numerical aspects are analyzed this review. In addition, many new approximation methods been developed order overcome limitations. New effective nucleon-nucleon...
By assuming the existence of a pseudopotential smooth enough to do Hartree-Fock variations and good describe nuclear structure, we construct mass formulas that rely on general scaling arguments schematic reading shell model calculations. Fits 1751 known binding energies for N,Z\ensuremath{\ge}8 lead rms errors 375 keV with 28 parameters. Tests extrapolation properties are passed successfully. The Bethe-Weizs\"acker formula is shown be asymptotic limit present one(s). surface energy matter...
An exact shell-model calculation is presented that gives a good description of the properties O16 and neighboring nuclei.Received 27 May 1968DOI:https://doi.org/10.1103/PhysRevLett.21.39©1968 American Physical Society
The residual part of the realistic forces---obtained after extracting monopole terms responsible for bulk properties---is strongly dominated by pairing and quadrupole interactions, with important \ensuremath{\sigma}\ensuremath{\tau}\ensuremath{\cdot}\ensuremath{\sigma}\ensuremath{\tau}, octupole, hexadecapole contributions. Their forms retain simplicity traditional plus multipole models, while eliminating their flaws through a normalization mechanism dictated universal...
Exact diagonalizations with a minimally modified realistic force lead to detailed agreement measured level schemes and electromagnetic transitions in $^{48}$Ca, $^{48}$Sc, $^{48}$Ti, $^{48}$V, $^{48}$Cr $^{48}$Mn. Gamow-Teller strength functions are systematically calculated reproduce the data within standard quenching factor. Their fine structure indicates that fragmentation makes much unobservable. As by-product, calculations suggest microscopic description of onset rotational motion. The...
We have calculated the Gamow-Teller matrix elements of 64 decays nuclei in mass range $A=41\ensuremath{-}50$. In all cases valence space full $\mathrm{pf}$ shell is used. Agreement with experimental results demands introduction an average quenching factor $q=0.744\ifmmode\pm\else\textpm\fi{}0.015$ slightly smaller but statistically compatible $\mathrm{sd}$-shell value, thus indicating that present number close to limit for large $A$.
A detailed shell-model description of ${\mathrm{F}}^{18}$ and ${\mathrm{O}}^{18}$ is given for all levels known spin parity. New assignments are suggested. It shown that a weak-coupling model highly successful in reproducing the exact results.
Binding energies and other global properties of nuclei in the middle $\mathrm{pf}$ shell, such as $M1,E2,$ Gamow-Teller sum rules, have been obtained using a new shell model code (NATHAN) written quasispin formalism $j\ensuremath{-}j$-coupled basis. An extensive comparison is made with recently available Monte Carlo results effective interaction KB3. The binding for nearly all ${1f}_{7/2}$ are compared measured (and extrapolated) results.
Exact diagonalizations with a realistic interaction show that configurations four neutrons in major shell and protons another---or the same---major shell, behave systematically as backbending rotors. The dominance of q\ensuremath{\cdot}q component is related to an approximate ``quasi-SU3'' symmetry. It suggested onset rotational motion rare earth nuclei due promotion eight particle blocks shells above ones currently filling. Assuming ``pseudo-SU3'' coupling for particles lower orbits, it...
The collective yrast band of the nucleus ${}^{48}\mathrm{Cr}$ is studied using spherical shell model and Hartree-Fock-Bogoliubov (HFB) method. Both approaches produce basically same axially symmetric intrinsic state up to the---accurately reproduced---observed backbending. Agreement between both calculations extends most observables. only significant discrepancy comes from static moments inertia can be attributed need a more refined treatment pairing correlations in HFB calculation.
The isovector and isotensor energy differences between yrast states of isobaric multiplets in the lower half pf region are quantitatively reproduced a shell model context. isospin nonconserving nuclear interactions found to be at least as important Coulomb potential. Their channels dominated by J=2 J=0 pairing terms, respectively. results sensitive radii states, whose evolution along band can accurately followed.
It is argued that there exist natural shell model spaces optimally adapted to the operation of two variants Elliott' SU3 symmetry provide accurate predictions quadrupole moments deformed states. A selfconsistent Nilsson-like calculation describes competition between realistic force and central field, indicating a {\em remarkable stability quadruplole moments}---which remain close their quasi pseudo values---as single particle splittings increase. detailed study $N=Z$ even nuclei from...
Complete diagonalizations in the $\mathrm{pf}$ major shell lead to very good agreement with experimental data (level schemes, transitions rates, and static moments) for $A=47$ $A=49$ isotopes of Ca, Sc, Ti, V, Cr, Mn. Gamow-Teller $M1$ strength functions are calculated. The necessary monopole modifications realistic interactions shown be critically tested by spectroscopic factors one particle transfer from ${}^{48}$Ca, reproduced detail calculations. collective behavior ${}^{47}$Ti, mirror...
It is shown that a very simple three-body monopole term can solve practically all the spectroscopic problems-in p, sd, and pf shells-that were hitherto assumed to need drastic revisions of realistic potentials.
The neutron-rich lead isotopes, up to $^{216}\mathrm{Pb}$, have been studied for the first time, exploiting fragmentation of a primary uranium beam at FRS-RISING setup GSI. observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands introduction effective three-body interactions and two-body operators in conventional neutron valence space beyond $^{208}\mathrm{Pb}$.
The monopole Hamiltonian ${H}_{m}$ is defined as the part of interaction that reproduces average energies configurations. After separating bulk contributions, we propose a minimal form for containing six parameters adjusted to reproduce spectra particle and hole states on doubly magic cores. mechanism shell formation then explained. reliability parametrization checked by showing predicted particle-hole gaps are consistent with experimental data, matrix elements obtained provide...
Gamma rays from the N=Z−2 nucleus 50Fe have been observed, establishing rotational ground state band up to Jπ=11+ at 6.994 MeV excitation energy. The experimental Coulomb energy differences, obtained by comparison with isobaric analog states in its mirror 50Cr, confirm qualitative interpretation of backbending patterns terms successive alignments proton and neutron pairs. A quantitative agreement experiment has achieved exact shell model calculations, incorporating differences radii along...
Excited states have been studied in 35Ar following the 16O(24Mg,1alpha1n)35Ar fusion-evaporation reaction at 60 MeV using Ge-detector array GASP. A comparison with mirror nucleus 35Cl shows two remarkable features: (i) surprisingly large energy difference for 13/2(-) states, which hitherto overlooked electromagnetic spin-orbit term is shown to play a major role, and (ii) very different decay pattern 7/2(-) provides direct evidence of isospin mixing.
We demonstrate the feasibility of realistic Shell-Model Monte Carlo (SMMC) calculations spanning multiple major shells, using a interaction whose bad saturation and shell properties have been corrected by newly developed general prescription. Particular attention is paid to approximate restoration translational invariance. The model space consists full sd-pf shells. include in study some well-known T=0 nuclei several unstable neutron-rich ones around N=20,28. results indicate that SMMC can...
Gamow-Teller strength functions in the resonance region are calculated full $(\mathrm{pf}{)}^{8}$ space. The observed profile is very sensitive to level density and may become so diluted as be confused with background. A model independent proof given that standard quenching originates nuclear correlations, some 30% of total must due states outside By combining this argument results shell calculations, comparison ${}^{48}\mathrm{Ca}(p,n{)}^{48}\mathrm{Sc}$ experimental data strongly suggest...
The collective yrast band and the high spin states of nucleus $^{50}\mathrm{Cr}$ are studied using spherical shell model cranked Hartree-Fock-Bogoliubov method. two descriptions lead to nearly same values for relevant observables. A first backbending is predicted at $I=10\ensuremath{\hbar}$ corresponding a noncollective transition. At $J=16\ensuremath{\hbar}$ second occurs, associated configuration change that can also be interpreted as triaxial