Conveners
Session 13B
- Heather Crawford (LBNL, USA)
In this talk, I will discuss an ab initio approach which exploits symplectic symmetry in order to provide a physically informed basis that successfully describes collective and clustering features, including quadrupole moments, electromagnetic transitions, as well as alpha widths, in light to intermediate-mass nuclei [1, 2, 3]. Looking towards the high-precision physics era, we study...
We present the first triaxial beyond-mean-field studies of super-heavy nuclei. They include the restoration of the particle-number and angular-momentum symmetries and the mixing of different shapes using the generator coordinate method. The importance of the $\gamma$ degree of freedom is highlighted by comparing the triaxial to axial-symmetric calculations performed within the same framework....
Exotic nuclei, far from stability, are a perfect laboratory to probe the specific components of the nuclear interaction. The imbalance between the number of protons and neutrons can lead to the appearance of phenomena such as sudden shape transitions and shape coexistence. The nuclei with Z and N around 40 and 60, respectively, show one of the most remarkable examples of sudden nuclear shape...
The empirical or semi-phenomenological nucleon-nucleon interactions that have been used in the traditional shell model studies for over half a century still play a key role in microscopic studies of nuclei. Progress has been made in connecting the empirical matrix elements of the Hamiltonian with the fundamental interactions coming from QCD, however full understanding is still missing. The...
Shape evolution in atomic nuclei has been a major area of research in nuclear physics. While throughout the nuclear chart the evolution of a spherical ground-state shape into a deformed one is usually a gradual process, in the Zr isotopic chain an abrupt shape transition is observed at N=60. Recent state-of-the-art Monte Carlo Shell Model (MCSM) calculations have successfully reproduced this...
In this contribution we discuss the investigation of the shape coexistence phenomenon in neutron-rich Selenium (Z=34) isotopes ($^{83}$Se and $^{84}$Se), near the N=50 neutron shell closure, by gamma-ray spectroscopy. The shape coexistence phenomenon consists in the appearance of different shapes (spherical, oblate and prolate) within the same nucleus at comparable excitation energies [1], and...
Following the main objective of the IAEA Coordinated Research Project on Photonuclear Data and Photon Strength Functions (Code F41032; Duration 2016-2019), new measurements of photoneutron and photofission cross sections in the Giant Dipole Resonance energy region have been performed at the laser Compton-scattering $\gamma$-ray source of the NewSUBARU synchrotron radiation facility. Nuclei in...
At EC-JRC Geel, the VESPA setup [1], made of a position-sensitive double Frisch-grid ionization chamber surrounded by $\mathrm{LaBr}_3$(Ce) scintillation detectors, is dedicated to multi-parameter measurements on ${}^{252}\mathrm{Cf}$(sf). The fission process generates highly excited nuclei. These nuclei will dissipate their excitation energy and angular momentum through the emission of...
