Download Free Nuclear Structure In The Vicinity Of 78ni Book in PDF and EPUB Free Download. You can read online Nuclear Structure In The Vicinity Of 78ni and write the review.

Thanks to advances in production of radioactive nuclear beams in the last two decades, we are able to study nuclear systems very far from stability. The region of the nuclear landscape in the vicinity of 78Ni remains still unexplored. This region, with very neutron-rich 78Ni hypothetically considered as a doubly magic core, is interesting in terms of nuclear structures. The experimental information is equally important to guide the emerging shell-model effective interactions in this region. We have studied -decay of a neutron rich 84Ga isotope at the ALTO facility in IPN Orsay (France). The fission fragments were produced with photo-fission reaction induced by 50 MeV electron beam in a thick UCx target. For the first time the maximum electron driver beam intensity at ALTO - 10uA - was used. The gallium atoms were selectively ionized with a newly developed laser ion source. With this ion source the ionization of the gallium was more than ten times higher compared to the surface ion source previously used by our group. The ions were separated with the PARRNe mass separator and implanted on a movable mylar tape. Two germanium detectors in close geometry were used for the detection of gamma-rays and gamma-gamma coincidence measurement, and a plastic for beta tagging. We present the results of our experiment: the improved level schemes of the neutron-rich 83,84Ge and 84As isotopes. We discuss their structure and compare the experimental results with the shell model calculations made with the new effective interaction ni78-jj4b with 78Ni core, constructed in the framework of this thesis.
The nuclear shell structure is evolving when going into more and more exotic regions of the chart of isotopes and consequently, the conventional magic numbers (8, 20, 28, 50, 82, 126) may disappear far from stability, while some new magic numbers can appear. The 78Ni nucleus, with its 28 protons and 50 neutrons, is one of the most exotic supposedly doubly-magic nuclei, making it of great interest. The evolution of the Z = 28 gap towards N = 50 can be studied by probing the single-particle character of the states in the copper isotopic chain, having one proton more than nickel. This work focuses on Cu, at N = 50.In the aim of performing the first in-beam gamma-ray spectroscopy of nuclei in the close vicinity of 78Ni, an experiment was carried out at the Radioactive Isotope Beam Factory of RIKEN, in Japan. The 79Cu nucleus was produced through the (p,2p) knockout reaction from a 80Zn beam sent on the MINOS device, a liquid-hydrogen target coupled to a TPC used for proton tracking. The subsequent gamma-decay was detected in-beam with the DALI2 scintillator array. The BigRIPS and ZeroDegree spectrometers allowed an unambiguous identification of the incoming and outgoing nuclei, respectively.An analysis procedure based on gamma-gamma coincidences permitted to build the first level scheme of 79Cu, with levels up to 4.6 MeV, and the results were compared to Monte-Carlo shell-model calculations for interpretation. The conclusions show that the 79Cu nucleus is well described in terms of a valence proton outside a closed 78Ni core, implying the magic character of the latter.
The evolution of single-particle states in neutron-rich nuclei provides a key information on their nuclear structure and is an important ingredient for the development of nuclear models that can be applied to predict the structure at the borderline of nuclear map. The role of neutron excitations across shell gaps and the evolution proton-neutron interaction can be studied in these exotic nuclei. In particular, magic nuclei are key players for the mapping of the single-particle degrees of freedom around closed cores. A special region of interest is found around the doubly-magic 78 28Ni50. In addition, gross properties of these nuclei play a role in the astrophysical rapid neutron capture process. Nuclei in the vicinity of 78Ni have motivated recent experimental and theoretical studies, aimed at the understanding of the nuclear structure in this region with a large neutron excess. In this thesis we investigate the nuclear structure of 81;80Ga, 81Ge and 81As, populated in the decay chain of 81Zn, which was produced at ISOLDE, CERN in the framework of a systematic fast-timing investigation of neutron-rich nuclei populated in the decay of Zn. The selectivity and efficiency of the production of Zn ion beams had been previously optimized in order to guarantee the most pure beam of 77{u100000}82Zn nuclei. The estimated yield of 81Zn was 600 ions/ C giving an average activity of particles during the experiment of about 10000 counts per second. The experimental setup included two HPGe detectors, two LaBr3(Ce) detectors and a NE111A plastic scintillator for particle detection. Coincidences with the detector were used for -ray background suppression, and - coincidences between the HPGe detectors to determine the level schemes. For half-life measurements the combination of LaBr3(Ce) scintillator crystals and Time-to- Amplitude Converters was employed. The signals from the detectors were processed by a digital data acquisition (DAQ) system composed by four Pixie-4 Digital Gamma Finder cards, specially designed for -ray spectroscopy which was used for decay level schemes and the Advanced Time Delayed (“fast-timing“) (t) method employed to measure the excited level lifetimes. From the structural point of view, the isotopes under study are relatively simple systems with a few particles and/or holes outside the doubly-magic core, and thus can be treated rather successfully within the nuclear shell model...
Physicists have devoted much effort to reproducing the conditions of the primordial universe in laboratory conditions in their quest to work out a comprehensive theory of the appearance and evolution of nuclear matter. Whether it be trying to recreate the predicted primordial state of high-energy density matter in which quarks and gluons are effectively deconfined - the so-called Quark Gluon Plasma (QGP) - or exploring the structure and reaction properties of very unstable nuclei in experiments using radioactive beams, they have striven to understand the events which characterized the Big Bang and the various nucleosynthesis mechanisms which occur in the stars. This book contains the proceedings of the 2010 Enrico Fermi summer school held in Varenna, Italy, in July 2010, and devoted to the present understanding of the primordial universe and the origin of the elements, as achieved by studying nuclei and their constituents in extreme regimes of energy and composition. Subjects covered include: QGP formation; exotic nuclei, their degrees of freedom from the ground state and the properties of the excited states; the complex, but appealing theory describing the supernovae explosion and neutron stars; dark energy and matter; Big Bang nucleosynthesis and energy and solar neutrino production; nuclear cosmochronology; beta and gamma decay relevant for the nucleosynthesis of heavy nuclei. The annual Enrico Fermi summer school is internationally renowned and this book will be of great interest to all those involved in the field of nuclear physics.
This book aims to cover a wide spectrum of research activities, both theoretical and experimental, in nuclear structure, nuclear astrophysics and nuclear reactions. Topics included are: nuclear structure under extreme conditions; collective phenomena and phase transitions; ground-state properties and synthesis of the heaviest elements; advances in mean field theories; modern shell model; cluster models and molecular dynamics; achievements in weak-interaction processes; nucleon scattering and more.
The 9th Conference on Problems in Theoretical Nuclear Physics was organized as part of the project “Theoretical Physics of Nuclei and Many-Body Systems” involving 17 Italian universities and sponsored by the Italian Ministry of Research and University.This volume includes the invited papers on the main subjects of the project and all the individual contributions on special topics. It reviews the work performed in the last two years by the participating Italian community of nuclear theorists. In addition, national and international perspectives are focussed by a panel on the future programmes of the large Italian laboratories and of the experimental community, as well as in a general review by A Faessler.
The acceleration of radioactive beams is a new and attractive field in nuclear physics. One of the most intense sources of very neutron-rich radioactive isotopes can be obtained by fission in a special uranium target close to the core of a research reactor. Two such installations are being planned: the PIAFE project in Grenoble and a similar facility at the new Munich research reactor FRM II. Accelerated fission fragments will facilitate the production of the heaviest elements by fusion and the investigation of nuclear structure and nuclear reactions for astrophysical purposes. This book discusses the application of fission fragments for many research fields.
Crete, Greece, 10-14 September 2007
The International Conference on Exotic Nuclei and Atomic Masses (ENAM) has gained the status of the premier meeting for the physics of nuclei far from stability. The selected and refereed papers presenting the main results constitute valuable proceedings that offer everyone working in this field an authoritative and comprehensive source of reference.