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Sample records for exotic nuclear structure

  1. Exotic nuclei: another aspect of nuclear structure

    International Nuclear Information System (INIS)

    Dobaczewski, J.; Blumenfeld, Y.; Flocard, H.; Garcia Borge, M.J.; Nowacki, F.; Rombouts, S.; Theisen, Ch.; Marques, F.M.; Lacroix, D.; Dessagne, P.; Gaeggeler, H.

    2002-01-01

    This document gathers the lectures made at the Joliot Curie international summer school in 2002 whose theme that year was exotic nuclei. There were 11 contributions whose titles are: 1) interactions, symmetry breaking and effective fields from quarks to nuclei; 2) status and perspectives for the study of exotic nuclei: experimental aspects; 3) the pairing interaction and the N = Z nuclei; 4) borders of stability region and exotic decays; 5) shell structure of nuclei: from stability to decay; 6) variational approach of system with a few nucleons; 7) from heavy to super-heavy nuclei; 8) halos, molecules and multi-neutrons; 9) macroscopic approaches for fusion reactions; 10) beta decay: a tool for spectroscopy; 11) the gas phase chemistry of super-heavy elements

  2. International symposium on exotic nuclear structures. Book of abstracst

    International Nuclear Information System (INIS)

    2000-01-01

    The following topics were discussed at the meeting: Physics of weakly bound nuclei, neutron skin and halo; Evolution of shell structures for neutron-rich nuclei; Collective excitations in nuclei with exotic nuclear shapes; Cluster structures; Super- and hyperdeformed nuclei, exotic structures in the actinides; Superheavy elements; Towards understanding the structure of nucleons; New experimental techniques, facilities for radioactive beams. All abstracts (75 items) were submitted as full text to the INIS database. (R.P.)

  3. Exotic nuclear structures and decays: new nuclear collective phenomena

    International Nuclear Information System (INIS)

    Hamilton, J.H.

    1986-01-01

    Studies of the properties of exotic nuclei have revealed a surprising richness and diversity in their shapes, structures, and decay modes far exceeding our understandings and expectations of even a decay ago. From studies of far-off-stability exotic nuclei have come evidence for the coexistence of different nuclear shapes in the same nucleus, new regions of unusually large deformation, new ground-state phase transitions from one shape to another, new magic numbers but now for deformed shapes, and for the importance of reinforcing shell gaps. New exotic decay modes include a wide variety of beta delayed particle emission and heavy cluster emissions such as 14 C and 24 Ne. The new deformed magic numbers of 38 and 60 seen far off stability clearly support that there are likely other ''magic'' numbers for protons and neutrons which give stability to different deformed shapes. Perhaps these other new magic shell gap numbers at large deformation could influence the sticking of two very heavy nuclei in collisions such as U on Cm. Finally, another area which could have a bearing on the formation, motions, and structures of giant nuclear systems involves the recent observation of very energetic, light particle (proton, alpha) emission with up to 50% and more of the total incoming energy in a collision, for example in 300 MeV 32 S on Ta. 43 refs., 11 figs., 2 tabs

  4. Nuclear structure studies of exotic nuclei. Progress report, September 1, 1996--August 31, 1997

    International Nuclear Information System (INIS)

    Winger, J.A.

    1997-05-01

    This report concerns the current status of the project 'Nuclear Structure Studies of Exotic Nuclei'. Discussed in this report are experiments performed during the current year, status of data analysis, plans and proposals for future experiments, conferences attended, equipment purchases related to the project, and use of graduate and undergraduate students

  5. Nuclear moments as a probe of electronic structure in material, exotic nuclear structure and fundamental symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Matsuta, K., E-mail: matsuta@vg.phys.sci.osaka-u.ac.jp; Minamisono, T.; Mihara, M.; Fukuda, M. [Osaka Univ., Dept. of Physics (Japan); Zhu, Shengyun [CIAE (China); Masuda, Y. [High Energy Accelerator Research Organization (KEK) (Japan); Hatanaka, K. [Osaka Univ., RCNP (Japan); Yuan Daqing; Zheng Yongnan; Zuo Yi; Fang Ping; Zhou Dongmei [CIAE (China); Ohtsubo, T. [Niigata Univ., Dept. of Physics (Japan); Izumikawa, T. [Niigata Univ., RI Center (Japan); Momota, S. [Kochi Univ. of Technology (Japan); Nishimura, D. [Tokyo Univ. of Science (Japan); Matsumiya, R. [Osaka Univ., RCNP (Japan); Kitagawa, A.; Sato, S.; Kanazawa, M. [Nat. Inst. Radiological Sciences (Japan); Collaboration: Osaka-CIAE-NIRS-Niigata-Kochi-LBL Collaboration; and others

    2013-05-15

    We report our studies in various fields of Physics through nuclear moments utilizing the {beta}-NMR technique, including material sciences, nuclear structures and fundamental symmetries. Especially, we focus on the recent progress in the studies on the electronic structure in Pt through Knight shifts of various impurities, lattice locations of impurities, electric field gradients, the analysis of nuclear spin in terms of its components, anomaly in the spin expectation value for {sup 9}C-{sup 9}Li mirror pair, the G-parity conservation law, and the Ramsey resonance on UCN for future neutron EDM measurements.

  6. Nuclear structure for the crust of neutron stars and exotic nuclei

    International Nuclear Information System (INIS)

    Goegelein, Peter

    2007-01-01

    In this work the Skyrme Hartree-Fock and Relativistic Hartree--Fock approaches have been considered to describe the structure of nuclear systems ranging from finite nuclei, structures in the crust of neutron stars to homogeneous matter. Effects of pairing correlations and finite temperature are also taken into account. The numerical procedure in the cubic box is described for the Skyrme Hartree-Fock as well as the relativistic Hartree-Fock approach. And finally, results for the crust of neutron stars and exotic nuclei are presented and discussed. (orig.)

  7. Nuclear structure for the crust of neutron stars and exotic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Goegelein, Peter

    2007-07-01

    In this work the Skyrme Hartree-Fock and Relativistic Hartree--Fock approaches have been considered to describe the structure of nuclear systems ranging from finite nuclei, structures in the crust of neutron stars to homogeneous matter. Effects of pairing correlations and finite temperature are also taken into account. The numerical procedure in the cubic box is described for the Skyrme Hartree-Fock as well as the relativistic Hartree-Fock approach. And finally, results for the crust of neutron stars and exotic nuclei are presented and discussed. (orig.)

  8. Introduction to the nuclear structure studies of exotic nuclei by using antisymmetrized molecular dynamics method

    International Nuclear Information System (INIS)

    Kimura, Masaaki; Dote, Akinobu; Ohnishi, Akira; Matsumiya, Hiroshi

    2009-01-01

    This article is originally prepared as the course text for the practice of the AMD course of 'studies of the strangeness nuclei by using the antisymmetrized molecular dynamics (AMD) method' in the Summer School held at KEK and IPCR in 2006-8 for postgraduate as well as undergraduate students and to foster young physicists in the titled area. The fundamental principle and the formalism of the AMD method which have been commonly used in the nuclear physics are explained at first, and it is described how to extend the AMD method to the studies of exotic nuclei especially to hypernuclei. Then calculation procedure is explained in detail so that the readers can understand the structure of exotic nuclei as they follow the process by themselves. It is intended here that they will be able not only to become familiar with the research by using the AMD method but also to visually enjoy the structure of exotic nuclei and will have further interest in this field. (S. Funahashi)

  9. Universal correlations of nuclear observables and the structure of exotic nuclei

    International Nuclear Information System (INIS)

    Casten, R.F.; Zamfir, N.V.

    1996-01-01

    Despite the apparent complexity of nuclear structural evolution, recent work has shown a remarkable underlying simplicity that is unexpected, global, and which leads to new signatures for structure based on the easiest-to-obtain data. As such they will be extremely valuable for use in the experiments with low intensity radioactive beams. Beautiful correlations based either on extrinsic variables such as N p N n or the P-factor or correlations between collective observables themselves have been discovered. Examples to be discussed include a tri-partite classification of structural evolution, leading to a new paradigm that discloses certain specific classes of nuclei, universal trajectories for B(E2: w 1 + → 0 1 + ) values and their use in extracting hexadecapole deformations from this observable alone, the use of these B(E2) values to identify shell gaps and magic numbers in exotic nuclei, the relationship of β and γ deformations, and single nucleon separation energies. Predictions for nuclei far off stability by interpolation will also be discussed

  10. Exotic nuclear excitations

    CERN Document Server

    Pancholi, S C

    2011-01-01

    By providing the reader with a foundational background in high spin nuclear structure physics and exploring exciting current discoveries in the field, this book presents new phenomena in a clear and compelling way. The quest for achieving the highest spin states has resulted in some remarkable successes which this monograph will address in comprehensive detail. The text covers an array of pertinent subject matter, including the rotational alignment and bandcrossings, magnetic rotation, triaxial strong deformation and wobbling motion and chirality in nuclei. Dr. Pancholi offers his readers a clearly-written and up-to-date treatment of the topics covered. The prerequisites for a proper appreciation are courses in nuclear physics and nuclear models and measurement techniques of observables like gamma-ray energies, intensities, multi-fold coincidences, angular correlations or distributions, linear polarization, internal conversion coefficients, short lifetime (pico-second range) of excited states etc. and instrum...

  11. Exotic nuclei: another aspect of nuclear structure; Les noyaux exotiques: un autre regard sur la structure nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Dobaczewski, J [Warsaw Univ., Institute of Theoretical Physics (Poland); Blumenfeld, Y; Flocard, H; Garcia Borge, M J; Nowacki, F; Rombouts, S; Theisen, Ch; Marques, F M; Lacroix, D; Dessagne, P; Gaeggeler, H

    2002-07-01

    This document gathers the lectures made at the Joliot Curie international summer school in 2002 whose theme that year was exotic nuclei. There were 11 contributions whose titles are: 1) interactions, symmetry breaking and effective fields from quarks to nuclei; 2) status and perspectives for the study of exotic nuclei: experimental aspects; 3) the pairing interaction and the N = Z nuclei; 4) borders of stability region and exotic decays; 5) shell structure of nuclei: from stability to decay; 6) variational approach of system with a few nucleons; 7) from heavy to super-heavy nuclei; 8) halos, molecules and multi-neutrons; 9) macroscopic approaches for fusion reactions; 10) beta decay: a tool for spectroscopy; 11) the gas phase chemistry of super-heavy elements.

  12. Nuclear Structure Studies On Exotic Nuclei With Radioactive Beams - Present Status And Future Perspectives At FAIR

    International Nuclear Information System (INIS)

    Peter Egelhof

    2011-01-01

    The investigation of nuclear reactions using radioactive beams in inverse kinematics gives access to a wide field of nuclear structure studies in the region far off stability. The basic concept and the methods involved are briefly discussed, and an overview including some selected examples of recent results obtained with radioactive beams from the present fragment separator at GSI Darmstadt is presented. The experimental conditions expected at the future international facility FAIR will, among others, allow for a substantial improvement in intensity and quality of radioactive beams as compared to present facilities. Therefore, it is expected that FAIR will provide unique opportunities for nuclear structure studies on nuclei far off stability, and will allow to explore new regions in the chart of nuclides of high interest for nuclear structure and nuclear astrophysics. A brief overview on the new facility, and on the experimental setups planned for nuclear structure research with radioactive beams is given. For nuclear reaction studies several complex, highly efficient, high resolution, and universal detection systems such as R 3 B, EXL, ELISe, etc. are presently under design and construction. A brief overview on the research objectives and the technical realization will be presented. (author)

  13. Nuclear Structure Studies of Exotic Nuclei with Radioactive Ion Beams A Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Winger, Jeff Allen [Mississippi State Univ., Mississippi State, MS (United States)

    2016-04-21

    Beta-decay spectroscopy provides important information on nuclear structure and properties needed to understand topics as widely varied as fundamental nuclear astrophysics to applied nuclear reactor design. However, there are significant limitations of our knowledge due to an inability to experimentally measure everything. Therefore, it is often necessary to rely on theoretical calculations which need to be vetted with experimental results. The focus of this report will be results from experimental research performed by the Principal Investigator (PI) and his research group at Mississippi State University in which the group played the lead role in proposing, implementing, performing and analyzing the experiment. This research was carried out at both the National Superconduction Cyclotron Laboratory (NSCL) at Michigan State University and the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory. The primary emphasis of the research was the use of \\bdec spectroscopy as a tool to understand the evolution of nuclear structure in neutron-rich nuclei which could then be applied to improve theory and to increase the overall knowledge of nuclear structure.

  14. Structures of exotic nuclei

    International Nuclear Information System (INIS)

    Hamilton, J.H.

    1987-01-01

    Discoveries of many different types of nuclear shape coexistence are being found at both low and high excitation energies throughout the periodic table, as documented in recent reviews. Many new types of shape coexistence have been observed at low excitation energies, for examples bands on more than four different overlapping and coexisting shapes are observed in 185 Au, and competing triaxial and prolate shapes in 71 Se and 176 Pt. Discrete states in super-deformed bands with deformations β 2 ∼ 0.4-0.6, coexisting with other shapes, have been seen to high spin up to 60ℎ in 152 Dy, 132 Ce and 135 Nd. Super-deformed nuclei with N and Z both around 38 and around Z = 38, N ≥ 60. These data led to the discovery of new shell gaps and magic numbers of 38 for N and Z and 60 for N but now for deformed shapes. Marked differences in structure are observed at spins of 6 to 20 in nuclei in this region, which differ by only two protons; for example, 68 Ge and 70 Se. The differences are thought to be related to the competing shell gaps in these nuclei

  15. Exotic cluster structures on

    CERN Document Server

    Gekhtman, M; Vainshtein, A

    2017-01-01

    This is the second paper in the series of papers dedicated to the study of natural cluster structures in the rings of regular functions on simple complex Lie groups and Poisson-Lie structures compatible with these cluster structures. According to our main conjecture, each class in the Belavin-Drinfeld classification of Poisson-Lie structures on \\mathcal{G} corresponds to a cluster structure in \\mathcal{O}(\\mathcal{G}). The authors have shown before that this conjecture holds for any \\mathcal{G} in the case of the standard Poisson-Lie structure and for all Belavin-Drinfeld classes in SL_n, n<5. In this paper the authors establish it for the Cremmer-Gervais Poisson-Lie structure on SL_n, which is the least similar to the standard one.

  16. Probing the exotic structure of {sup 8}B by its elastic scattering and breakup reaction on nuclear targets

    Energy Technology Data Exchange (ETDEWEB)

    Lukyanov, V.K.; Zemlyanaya, E.V.; Lukyanov, K.V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kadrev, D.N.; Antonov, A.N.; Gaidarov, M.K. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); Spasova, K. [Bulgarian Academy of Sciences, Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); University ' ' Ep. K. Preslavski' ' , Shumen (Bulgaria)

    2017-02-15

    The structure of the exotic {sup 8}B nucleus is studied by means of elastic scattering, as well as its breakup on nuclear targets. We present microscopic calculations of the optical potentials (OPs) and cross sections of elastic scattering of {sup 8}B on {sup 12}C, {sup 58}Ni, and {sup 208}Pb targets at energies 20 < E < 170 MeV. The density distributions of {sup 8}B obtained within the variational Monte Carlo (VMC) model and the three-cluster model (3CM) are used to construct the potentials. The real part of the hybrid OP is calculated using the folding model with the direct and exchange terms included, while the imaginary part is obtained on the base of the high-energy approximation (HEA) and also taken to be equal to the microscopic real part of the OP. In this model the only free parameters are the depths of the real and imaginary parts of OP obtained by fitting the elastic scattering experimental data. A dependence of their values on the model density of {sup 8} B is found. In addition, the cluster model, in which {sup 8}B consists of a p-halo and the {sup 7} Be core, is applied to calculate the breakup cross sections of the {sup 8}B nucleus on {sup 9}Be, {sup 12}C, and {sup 197}Au targets, as well as momentum distributions of {sup 7}Be fragments, and a comparison with the existing experimental data is made. (orig.)

  17. Hadronic interaction and structure of exotic nuclei

    International Nuclear Information System (INIS)

    Otsuka, Takaharu

    2009-01-01

    I will overview recent studies on the evolution of the shell structure in stable and exotic nuclei, and will show its relevance to hadronic interaction, including nuclear forces. This shell evolution is primarily due to the tensor force. The robust mechanism and some examples will be presented. Such examples include the disappearance of existing magic numbers and the appearance of new ones. The shell structure and existing limit of nuclei depend also on the three-body interaction in a specific way. I will sketch how the Δ-hole excitation induced three-body force (Fujita-Miyazawa force) modifies them. (author)

  18. Nuclear Structure Effects in the Exotic Decay of $^{225}$Ac via $^{14}$C Emission

    CERN Multimedia

    2002-01-01

    % IS323 \\\\ \\\\ We propose to build at Isolde a high intensity $^{225}$Ac source by $\\beta$-decay of $^{225}$(Ra+Fr) beam, to be used at the superconducting spectrometer SOLENO of IPN-Orsay in order to study a possible fine structure in the spectrum of $^{14}$C ions spontaneously emitted by $^{225}$Ac.

  19. Nuclear Track Detectors. Searches for Exotic Particles

    CERN Document Server

    Giacomelli, Giorgio

    2008-01-01

    We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: i) Exposures at the SPS and at lower energy accelerator heavy ion beams for calibration purposes and for fragmentation studies. ii) Searches for GUT and Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso underground lab, with ~1000 m^2 of CR39 detectors (plus scintillators and streamer tubes), established an upper limit for superheavy GUT poles at the level of 1.4x10^-16 cm^-2 s^-1 sr^-1 for 4x10^-5 exotic particles. iii) Environmental studies, radiation monitoring, neutron dosimetry.

  20. Traditional nuclear physics as a test of nuclear exotics

    International Nuclear Information System (INIS)

    Sapershtein, E.E.; Starodubskii, V.E.

    1989-01-01

    The review considers the testing of some exotic hypotheses about the properties of the nucleon in a nuclear medium in phenomena of traditional nuclear physics. The hypothesis of nucleon swelling proposed to explain the EMC effects is considered in detail. The consequences of this hypothesis for the charge densities and cross sections for scattering of fast electrons and protons by nuclei are analyzed. Also considered are the Nolen--Schiffer anomaly, the Coulomb sum rule for inelastic electron scattering, y scaling, and some other nuclear processes. It is shown that one can estimate the possible scale of nuclear exotics by analyzing many of these phenomena. Thus, examination of high-precision data on the elastic scattering of electrons with energy 500--700 MeV using density distributions calculated on the basis of the self-consistent theory of finite Fermi systems yields a restriction on the amount of nucleon swelling: α=δr N /r N approx-lt 10%. A similar analysis for protons with energy 0.8--1.0 GeV using Glauber theory gives α approx-lt 6%. An even more stringent restriction, α approx-lt 3%, follows from data on y scaling in 56 Fe

  1. Parent di-nuclear quasimolecular states as exotic resonant states

    International Nuclear Information System (INIS)

    Grama, N.

    2002-01-01

    It in shown that the parent di-nuclear quasimolecular state is an exotic resonant state that corresponds to a S-matrix pole in the neighbourhood of an attractor in the k-plane. The properties of the parent quasimolecular states i.e. energy, widths, deviation from the linear dependence of the energy on l(l + 1) doorway character and criteria for observability, result naturally from the general properties of the exotic resonant states. (author)

  2. Study of nuclear level densities for exotic nuclei

    International Nuclear Information System (INIS)

    Nasrabadi, M. N.; Sepiani, M.

    2012-01-01

    Nuclear level density is one of the properties of nuclei with widespread applications in astrophysics and nuclear medicine. Since there has been little experimental and theoretical research on the study of nuclei which are far from stability line, studying nuclear level density for these nuclei is of crucial importance. Also, as nuclear level density is an important input for nuclear research codes, hence studying the methods for calculation of this parameter is essential. Besides introducing various methods and models for calculating nuclear level density for practical applications, we used exact spectra distribution (SPDM) for determining nuclear level density of two neutron and proton enriched exotic nuclei with the same mass number.

  3. Nuclear shapes: From the mundane to the exotic

    International Nuclear Information System (INIS)

    Yates, S.W.

    1994-01-01

    The collection of protons and neutrons that forms an atomic nucleus can be characterized as having a shape. Surprisingly, the nuclei of most atoms are not spherical but exhibit shapes that are football-like, pear-like, etc. Following a brief review of the characteristics of these open-quotes mundaneclose quotes nuclear shapes, recent observations of nuclei that are superdeformed or even hyperdeformed are presented. In addition, the evidence for more exotic nuclei that can be described as exhibiting halos, forming a nuclear sausage, or undergoing a scissors-like motion are examined. The discussion concludes with some speculation about additional exotic shapes, such as the nuclear banana. Since nuclear shapes cannot be observed directly, one must rely on knowledge from indirect sources. Some of the details about these sources of information, including excitation spectra and nuclear lifetimes, are presented

  4. Searches for exotic interactions in nuclear beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Naviliat-Cuncic, O. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, 640 S Shaw Lane, East Lansing MI 48824 (United States)

    2016-07-07

    This contribution presents current efforts in the search for exotic interactions in nuclear β decay using a calorimetric technique for the measurement of the β energy spectrum shape. We describe the criteria for the choice of sensitive candidates in Gamow-Teller transitions and present the status of measurements performed in {sup 6}He and {sup 20}F decay.

  5. A possible global group structure for exotic states

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xue-Qian [Nankai University, School of Physics, Tianjin (China); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China)

    2014-12-01

    Based on the fact that the long expected pentaquark which possesses the exotic quantum numbers of B = 1 and S = 1 was not experimentally found, although exotic states of XY Z have been observed recently, we conjecture that the heavy flavors may play an important role in stabilizing the hadronic structures beyond the traditional q anti q and qqq composites. (orig.)

  6. Exotic nuclear beta transitions astrophysical examples

    CERN Document Server

    Takahashi, K

    1981-01-01

    A theoretical study of nuclear beta -transitions under various astrophysical circumstances is reviewed by illustrative examples: 1) continuum-state electron captures in a matter in the nuclear statistical equiplibrium, and ii) bound-state beta -decays in stars in connection with a cosmochronometer and with the s-process branchings. (45 refs).

  7. Nuclear structure of weakly bound radioactive nuclei through elastic and and inelastic scattering on proton. Impacts of the couplings induced by these exotic nuclei on direct reactions

    International Nuclear Information System (INIS)

    Lapoux, V.

    2005-09-01

    Information on the structure, spectroscopy and target interaction potentials of exotic nuclei can be inferred by interpreting measured data from direct reactions on proton such as elastic or inelastic scattering of proton (p,p') or one-nucleon transfer reaction (p,d). A series of experimental results has been obtained at the GANIL facilities on the setting composed of the MUST telescope array used for the detection of light charged-particles and of CATS beam detectors. This setting aims at measuring reactions on light proton or deuteron targets through reverse kinematics. Particularly, results on C 10 , C 11 and on direct reactions with the He 8 beam of Spiral are presented. The first chapter is dedicated to the description of the most important theories concerning the nucleus. The experimental tools used to probe the nucleus are reported in the second chapter. The third and fourth chapters present the framework that has allowed us to analyse results from (p,p') and (p,d) reactions on weakly bound exotic nuclei. The last chapter is dedicated to the description of future experimental programs. (A.C.)

  8. SPES: exotic beams for nuclear physics studies

    International Nuclear Information System (INIS)

    Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Vasquez, J.; Rossignoli, M.; Monetti, A.; Calderolla, M.; Prete, G.

    2014-01-01

    The SPES project at Laboratori di Legnaro of INFN (Italy) is concentrating on the production of neutron-rich radioactive nuclei for nuclear physics experiments using uranium fission at a rate of 10 13 fission/s. The emphasis on neutron-rich isotopes is justified by the fact that this vast territory has been little explored. The Radioactive Ion Beam (RIB) will be produced by the ISOL technique using proton induced fission on a direct target of UCx. The most critical element of the SPES project is the Multi-Foil Direct Target. Up to the present time, the proposed target represents an innovation in terms of its capability to sustain the primary beam power. This talk will present the status of the project financed by INFN, which is actually in the construction phase at Legnaro. In particular, developments related to the target and the ion-source activities using the surface ion source, plasma ion source, and laser ion source techniques will be reported. (author)

  9. Masses of exotic calcium isotopes pin down nuclear forces

    CERN Document Server

    Wienholtz, F; Blaum, K; Borgmann, Ch; Breitenfeldt, M; Cakirli, R B; George, S; Herfurth, F; Holt, J D; Kowalska, M; Kreim, S; Lunney, D; Manea, V; Menéndez, J; Neidherr, D; Rosenbusch, M; Schweikhard, L; Schwenk, A; Simonis, J; Stanja, J; Wolf, R N; Zuber, K

    2013-01-01

    The properties of exotic nuclei on the verge of existence play a fundamental part in our understanding of nuclear interactions. Exceedingly neutron-rich nuclei become sensitive to new aspects of nuclear forces. Calcium, with its doubly magic isotopes $^{40}$Ca and $^{48}$Ca, is an ideal test for nuclear shell evolution, from the valley of stability to the limits of existence. With a closed proton shell, the calcium isotopes mark the frontier for calculations with three-nucleon forces from chiral effective field theory. Whereas predictions for the masses of $^{51}$Ca and $^{52}$Ca have been validated by direct measurements$^4$, it is an open question as to how nuclear masses evolve for heavier calcium isotopes. Here we report the mass determination of the exotic calcium isotopes $^{53}$Ca and $^{54}$Ca, using the multi-reflection time-of-flight mass spectrometer of ISOLTRAP at CERN. The measured masses unambiguously establish a prominent shell closure at neutron number N = 32, in excellent agreement with our t...

  10. The Array for Nuclear Astrophysics Studies with Exotic Nuclei

    Science.gov (United States)

    Linhardt, L. E.; Blackmon, J. C.; Matos, M.; Mondello, L. L.; Zganjar, E. F.; Johnson, E.; Rogachev, G.; Wiedenhover, I.

    2010-11-01

    The Array for Nuclear Astrophysics Studies with Exotic Nuclei (ANASEN) is a charged-particle detector array that is targeted primarily towards reaction studies with radioactive ion beams at FSU and the NSCL. ANASEN consists of 40 double-sided silicon-strip detectors backed with CsI scintillators and an innovative gas counter design that allows operation in a gas target/detector mode and experiments covering a broad range of center-of-mass energies simultaneously. Electronics based on ASIC components are being implemented to achieve a high channel count at low cost. Prototypes of all the detector components have been fabricated and are currently being tested. Performance of the individual components and plans for the first experiments that aim to improve our knowledge of the nuclear reactions important in stellar explosions will be reported.

  11. One-nucleon transfer reactions induced by secondary beam of 11Be: study of the nuclear structure of the exotic nuclei 11Be and 10Li

    International Nuclear Information System (INIS)

    Pita, S.

    2000-09-01

    The structure of the neutron rich light nuclei 11 Be and 10 Li has been investigated by means of one nucleon transfer reactions. The experiments have been carried out at GANIL in inverse kinematics using 11 Be secondary beams. The 11 Be(p,d) 10 Be reaction bas been studied at 35.3 MeV/u. The 10 Be ejectiles were analyzed by the spectrometer SPEG, and coincident deuterons were detected in the position sensitive silicon detector CHARISSA. Transfer cross sections to 0 + 1 and 2 + 1 , states in 10 Be were measured up to θ CM = 16 deg. and compared to DWBA and CRC predictions. The effects of neutron-cure couplings on reaction form factors have been studied by solving coupled equations in the framework of a vibrational model. It is shown that the rate of core excitation 10 Be 2+ in the 11 Be gs wave function is overestimated by a standard analysis with form factors given by the usual Separation Energy prescription. The former model predicts a rate of core excitation of 16% and leads to theoretical cross sections which are in good agreement with the experimental data. The aim of the 11 Be(d, 3 He) 10 Li experiment, realized at 37 MeV/u, was to measure the distribution of the 2s neutron strength in the unbound nucleus 10 Li. The energy spectrum was deduced from the 3 He energy and angle measured by the silicon strip detector array MUST. An asymmetric peak is clearly observed near the threshold, with a maximum at -S n = 130 keV. This constitutes a direct proof of the inversion of 2s and 1p 1/2 shells in 10 Li, which was until now a controversial question in spite of many experimental efforts. On the other band the analysis of the 11 Be(d,t) 10 Be reaction studied in the same experiment confirms the results obtained in the 11 Be(p,d) 10 Be reaction concerning the 11 Be gs structure. This work shows the interest and feasibility of studies of the shell properties of exotic nuclei using transfer reactions induced by radioactive beams and constitutes the beginning of a program

  12. Probing the partonic structure of exotic particles in hard electroproduction

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We argue that the electroproduction of exotic particles is a useful tool for study of their partonic structure. In the case of hybrid mesons, the magnitude of their cross sections shows that they are accessible for measurements in existing electroproduction experiments

  13. Structure of exotic nuclei and superheavy elements in meson field theory

    International Nuclear Information System (INIS)

    Linn, Khin Nyan

    2008-07-01

    In this work the nuclear structure of exotic nuclei and superheavy nuclei is studied in a relativistic framework. In the relativistic mean-field (RMF) approximation, the nucleons interact with each other through the exchange of various effective mesons (scalar, vector, isovector-vector). Ground state properties of exotic nuclei and superheavy nuclei are studied in the RMF theory with the three different parameter sets (ChiM,NL3,NL-Z2). Axial deformation of nuclei within two drip lines are performed with the parameter set (ChiM). The position of drip lines are investigated with three different parameter sets (ChiM,NL3,NL-Z2) and compared with the experimental drip line nuclei. In addition, the structure of hypernuclei are studied and for a certain isotope, hyperon halo nucleus is predicted. (orig.)

  14. Structure of exotic nuclei and superheavy elements in meson field theory

    Energy Technology Data Exchange (ETDEWEB)

    Linn, Khin Nyan

    2008-07-15

    In this work the nuclear structure of exotic nuclei and superheavy nuclei is studied in a relativistic framework. In the relativistic mean-field (RMF) approximation, the nucleons interact with each other through the exchange of various effective mesons (scalar, vector, isovector-vector). Ground state properties of exotic nuclei and superheavy nuclei are studied in the RMF theory with the three different parameter sets (ChiM,NL3,NL-Z2). Axial deformation of nuclei within two drip lines are performed with the parameter set (ChiM). The position of drip lines are investigated with three different parameter sets (ChiM,NL3,NL-Z2) and compared with the experimental drip line nuclei. In addition, the structure of hypernuclei are studied and for a certain isotope, hyperon halo nucleus is predicted. (orig.)

  15. Nuclear structure

    International Nuclear Information System (INIS)

    Eastham, D.A.; Joy, T.

    1986-01-01

    The paper on 'nuclear structure' is the Appendix to the Daresbury (United Kingdom) Annual Report 1985/86, and contains the research work carried out at the Nuclear Structure Facility, Daresbury, within that period. During the year a total of 74 experiments were scheduled covering the main areas of activity including: nuclear collective motion, nuclei far from stability, and nuclear collisions. The Appendix contains brief reports on these experiments and associated theory. (U.K.)

  16. β-Decay half-lives and nuclear structure of exotic proton-rich waiting point nuclei under rp-process conditions

    Science.gov (United States)

    Nabi, Jameel-Un; Böyükata, Mahmut

    2016-03-01

    We investigate even-even nuclei in the A ∼ 70 mass region within the framework of the proton-neutron quasi-particle random phase approximation (pn-QRPA) and the interacting boson model-1 (IBM-1). Our work includes calculation of the energy spectra and the potential energy surfaces V (β , γ) of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, N = Z. The parametrization of the IBM-1 Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy surfaces V (β , γ) obtained from the IBM-1 Hamiltonian in the classical limit. The pn-QRPA model was later used to compute half-lives of the neutron-deficient nuclei which were found to be in very good agreement with the measured ones. The pn-QRPA model was also used to calculate the Gamow-Teller strength distributions and was found to be in decent agreement with the measured data. We further calculate the electron capture and positron decay rates for these N = Z waiting point (WP) nuclei in the stellar environment employing the pn-QRPA model. For the rp-process conditions, our total weak rates are within a factor two compared with the Skyrme HF +BCS +QRPA calculation. All calculated electron capture rates are comparable to the competing positron decay rates under rp-process conditions. Our study confirms the finding that electron capture rates form an integral part of the weak rates under rp-process conditions and should not be neglected in the nuclear network calculations.

  17. Structure of the subsaturated nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Toshiki; Maruyama, Tomoyuki; Chiba, Satoshi; Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Niita, Koji; Oyamatsu, Kazuhiro

    1998-07-01

    Quantum molecular dynamics is applied to study the ground state and excited state properties of nuclear matter at subsaturation densities. The structure of nuclear matter at subsaturation density shows some exotic shapes with variation of the density. However, the structure in our result is rather irregular compared to those of previous works due to the existence of local minimum configurations. (author)

  18. Ab Initio Calculations Of Nuclear Reactions And Exotic Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Quaglioni, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-05-05

    Our ultimate goal is to develop a fundamental theory and efficient computational tools to describe dynamic processes between nuclei and to use such tools toward supporting several DOE milestones by: 1) performing predictive calculations of difficult-to-measure landmark reactions for nuclear astrophysics, such as those driving the neutrino signature of our sun; 2) improving our understanding of the structure of nuclei near the neutron drip line, which will be the focus of the DOE’s Facility for Rare Isotope Beams (FRIB) being constructed at Michigan State University; but also 3) helping to reveal the true nature of the nuclear force. Furthermore, these theoretical developments will support plasma diagnostic efforts at facilities dedicated to the development of terrestrial fusion energy.

  19. Structure of exotic nuclei by large-scale shell model calculations

    International Nuclear Information System (INIS)

    Utsuno, Yutaka; Otsuka, Takaharu; Mizusaki, Takahiro; Honma, Michio

    2006-01-01

    An extensive large-scale shell-model study is conducted for unstable nuclei around N = 20 and N = 28, aiming to investigate how the shell structure evolves from stable to unstable nuclei and affects the nuclear structure. The structure around N = 20 including the disappearance of the magic number is reproduced systematically, exemplified in the systematics of the electromagnetic moments in the Na isotope chain. As a key ingredient dominating the structure/shell evolution in the exotic nuclei from a general viewpoint, we pay attention to the tensor force. Including a proper strength of the tensor force in the effective interaction, we successfully reproduce the proton shell evolution ranging from N = 20 to 28 without any arbitrary modifications in the interaction and predict the ground state of 42Si to contain a large deformed component

  20. Calibrations of CR39 and Makrofol nuclear track detectors and search for exotic particles

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; De Marzo, C; De Mitri, I; De Vincenzi, M; Dekhissi, H; Derkaoui, J; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kumar, A; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Manzoor, S; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Matteuzzi, D; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R; 10.1016/S0920-5632(03)02249-7

    2003-01-01

    We present the final results of the search for exotic massive particles in the cosmic radiation performed with the MACRO underground experiment. Magnetic monopoles and nuclearites flux upper limits obtained with the CR39 nuclear track subdetector, the scintillation and streamer tube subdetectors are given. Searches at high altitude with the SLIM experiment are in progress.

  1. Nuclear spin content and constraints on exotic spin-dependent couplings

    International Nuclear Information System (INIS)

    Kimball, D F Jackson

    2015-01-01

    There are numerous recent and ongoing experiments employing a variety of atomic species to search for couplings of atomic spins to exotic fields. In order to meaningfully compare these experimental results, the coupling of the exotic field to the atomic spin must be interpreted in terms of the coupling to electron, proton, and neutron spins. Traditionally, constraints from atomic experiments on exotic couplings to neutron and proton spins have been derived using the single-particle Schmidt model for nuclear spin. In this model, particular atomic species are sensitive to either neutron or proton spin couplings, but not both. More recently, semi-empirical models employing nuclear magnetic moment data have been used to derive new constraints for non-valence nucleons. However, comparison of such semi-empirical models to detailed large-scale nuclear shell model calculations and analysis of known physical effects in nuclei show that existing semi-empirical models cannot reliably be used to predict the spin polarization of non-valence nucleons. The results of our re-analysis of nuclear spin content are applied to searches for exotic long-range monopole–dipole and dipole–dipole couplings of nuclei leading to significant revisions of some published constraints. (paper)

  2. Studies of the neutron single-particle structure of exotic nuclei at the HRIBF

    International Nuclear Information System (INIS)

    Thomas, J.S.; Bardayan, D.W.; Blackmon, J.C.; Cizewski, J.A.; Greife, U.; Gross, C.J.; Johnson, M.S.; Jones, K.L.; Kozub, R.L.; Liang, J.F.; Livesay, R.J.; Ma, Z.; Moazen, B.H.; Nesaraja, C.D.; Shapira, D.; Smith, M.S.

    2004-01-01

    The study of neutron single-particle strengths in neutron-rich nuclei is of interest for nuclear structure and nuclear astrophysics. The distribution of single-particle strengths constrains the effective Hamiltonian and pairing interactions and determines neutron interaction rates that are crucial for understanding the synthesis of heavy nuclei in supernovae via the rapid neutron capture process. Particularly important are the neutron single-particle levels in nuclei near closed neutron shells. Radioactive ion beams from the Holifield Radioactive Ion Beam Facility have been used to study (d,p) reactions in inverse kinematics in order to probe neutron single-particle states in exotic nuclei. The results of a measurement with a 82 Ge beam will be presented

  3. Nuclear structure

    International Nuclear Information System (INIS)

    Joy, T.; Price, H.G.

    1984-01-01

    The appendix to the Daresbury Annual report contains detailed summaries of experiments carried out, or in progress, for the period 1983/84, using the Nuclear Structure Facility tandem accelerator. The experimental work is carried out by University groups from the UK and abroad, and Daresbury Staff. Developments in instrumentation, and a report on the first year of scheduled operation of the Facility, are also given. (U.K.)

  4. Shell closures, loosely bound structures, and halos in exotic nuclei

    International Nuclear Information System (INIS)

    Saxena, G.; Singh, D.

    2013-01-01

    Inspired by the recent experiments indicating doubly magic nuclei that lie near the drip-line and encouraged by the success of our relativistic mean-field (RMF) plus state-dependent BCS approach to the description of the ground-state properties of drip-line nuclei, we develop this approach further, across the entire periodic table, to explore magic nuclei, loosely bound structures, and halo formation in exotic nuclei. In our RMF+BCS approach, the single-particle continuum corresponding to the RMF is replaced by a set of discrete positive-energy states for the calculations of pairing energy. Detailed analysis of the single-particle spectrum, pairing energies, and densities of the nuclei predict the unusual proton shell closures at proton numbers Z = 6, 14, 16, 34, and unusual neutron shell closures at neutron numbers N = 6, 14, 16, 34, 40, 70, 112. Further, in several nuclei like the neutron-rich isotopes of Ca, Zr, Mo, etc., the gradual filling of lowlying single-particle resonant state together with weakly bound single-particle states lying close to the continuum threshold helps accommodate more neutrons but with an extremely small increase in the binding energy. This gives rise to the occurrence of loosely bound systems of neutron-rich nuclei with a large neutron-to-proton ratio. In general, the halo-like formation, irrespective of the existence of any resonant state, is seen to be due to the large spatial extension of the wave functions for the weakly bound single-particle states with low orbital angular momentum having very small or no centrifugal barriers.

  5. Shell closures, loosely bound structures, and halos in exotic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, G., E-mail: gauravphy@gmail.com [Govt. Women Engineering College, Department of Physics (India); Singh, D. [University of Rajasthan, Department of Physics (India)

    2013-04-15

    Inspired by the recent experiments indicating doubly magic nuclei that lie near the drip-line and encouraged by the success of our relativistic mean-field (RMF) plus state-dependent BCS approach to the description of the ground-state properties of drip-line nuclei, we develop this approach further, across the entire periodic table, to explore magic nuclei, loosely bound structures, and halo formation in exotic nuclei. In our RMF+BCS approach, the single-particle continuum corresponding to the RMF is replaced by a set of discrete positive-energy states for the calculations of pairing energy. Detailed analysis of the single-particle spectrum, pairing energies, and densities of the nuclei predict the unusual proton shell closures at proton numbers Z = 6, 14, 16, 34, and unusual neutron shell closures at neutron numbers N = 6, 14, 16, 34, 40, 70, 112. Further, in several nuclei like the neutron-rich isotopes of Ca, Zr, Mo, etc., the gradual filling of lowlying single-particle resonant state together with weakly bound single-particle states lying close to the continuum threshold helps accommodate more neutrons but with an extremely small increase in the binding energy. This gives rise to the occurrence of loosely bound systems of neutron-rich nuclei with a large neutron-to-proton ratio. In general, the halo-like formation, irrespective of the existence of any resonant state, is seen to be due to the large spatial extension of the wave functions for the weakly bound single-particle states with low orbital angular momentum having very small or no centrifugal barriers.

  6. Nuclear reactions as structure probes

    International Nuclear Information System (INIS)

    Fernandez, Bernard; Cugnon, Joseph; Roussel-Chomaz, Patricia; Sparenberg, Jean-Marc; Oliveira Santos, Francois de; Bauge, Eric; Poves, Alfredo; Keeley, Nicholas; Simenel, Cedric; Avez, Benoit; Lacroix, Denis; Baye, Daniel; Cortina-Gil, Dolores; Pons, Alexandre

    2007-09-01

    This publication gathers courses which aim at giving a view on new experiments which are performed by using radioactive beams, notably low intensity beams, in different accelerators, and allow the structure of very exotic nuclei to be characterized. Experimental as well as theoretical aspects are thus addressed. The contributions propose: a brief history of nuclear reactions and of instruments used to study them from the discovery of nucleus to the DWBA (Distorted Wave Born Approximation); an overview of nuclear reactions; experimental techniques; the theory of collisions at low energy; resonant elastic scattering, inelastic scattering and astrophysical reactions; to probe nuclear structure with nucleons; shell model and spectroscopic factors; analysis of transfer reactions and determination of spectroscopic factors; microscopic approaches of nuclear dynamics; theoretical aspects of dissociation reactions; experimental aspects of knockout reactions; research in oenology with the chemical characterisation of defective ageing of dry white wines

  7. Theoretical nuclear structure and astrophysics at FAIR

    International Nuclear Information System (INIS)

    Rodríguez, Tomás R

    2014-01-01

    Next generation of radioactive ion beam facilities like FAIR will open a bright future for nuclear structure and nuclear astrophysics research. In particular, very exotic nuclei (mainly neutron rich) isotopes will be produced and a lot of new exciting experimental data will help to test and improve the current nuclear models. In addition, these data (masses, reaction cross sections, beta decay half-lives, etc.) combined with the development of better theoretical approaches will be used as the nuclear physics input for astrophysical simulations. In this presentation I will review some of the state-of-the-art nuclear structure methods and their applications.

  8. Exotic atoms

    International Nuclear Information System (INIS)

    Horvath, D.; Lambrecht, R.M.

    1984-01-01

    This bibliography on exotic atoms covers the years 1939 till 1982. The annual entries are headed by an introduction describing the state of affairs of the branch of science and listing the main applications in quantum electrodynamics, particle physics, nuclear physics, atomic physics, chemical physics and biological sciences. The bibliography includes an author index and a subject index. (Auth.)

  9. International Workshop on Exotic Hadronic Atoms, Deeply Bound Kaonic Nuclear States and Antihydrogen : Present Results, Future Challenges

    CERN Document Server

    Widmann, E; Curceanu, C; Trento 2006; Trento06

    2006-01-01

    These are the miniproceedings of the workshop "Exotic hadronic atoms, deeply bound kaonic nuclear states and antihydrogen: present results, future challenges," which was held at the European Centre for Theoretical Nuclear Physics and Related Studies (ECT*), Trento (Italy), June 19-24, 2006. The document includes a short presentation of the topics, the list of participants, and a short contribution from each speaker.

  10. Nuclear orientation and nuclear structure

    International Nuclear Information System (INIS)

    Krane, K.S.

    1988-01-01

    The present generation of on-line nuclear orientation facilities promises to revolutionize the gathering of nuclear structure information, especially for the hitherto poorly known and understood nuclei far from stability. Following a brief review of the technological developments that have facilitated these experiments, the nuclear spectroscopic information that can be obtained is summarized. Applications to understanding nuclear structure are reviewed, and challenges for future studies are discussed. (orig.)

  11. Probing the Evolution of the Shell Structures in Exotic Nuclei

    International Nuclear Information System (INIS)

    De Angelis, Giacomo

    2008-01-01

    Magic numbers are a key feature in finite Fermion systems since they are strongly related to the underlying mean field. The size of the shell gaps and their evolution far from stability can be linked to the shape and symmetry of the nuclear mean field. Moreover the study of nuclei with large neutron/proton ratio allow to probe the density dependence of the effective interaction. Changes of the nuclear density and size in nuclei with increasing N/Z ratios are expected to lead to different nuclear symmetries and excitations. In this contribution I will discuss some selected examples which show the big potential of stable beams and of binary reactions for the study of the properties of the neutron-rich nuclear many body systems.

  12. Novel nuclear laser spectroscopy method using superfluid helium for measurement of spins and moments of exotic nuclei

    International Nuclear Information System (INIS)

    Furukawa, Takeshi; Wakui, Takashi; Yang, Xiaofei; Fujita, Tomomi; Imamura, Kei; Yamaguchi, Yasuhiro; Tetsuka, Hiroki; Tsutsui, Yoshiki; Mitsuya, Yosuke; Ichikawa, Yuichi; Ishibashi, Yoko; Yoshida, Naoki; Shirai, Hazuki; Ebara, Yuta; Hayasaka, Miki; Arai, Shino; Muramoto, Sosuke

    2013-01-01

    Highlights: • Development of a novel nuclear laser spectroscopy method using superfluid helium. • Observation of the Zeeman resonance with the 85 Rb beam introduced into helium. • Demonstration of deducing the nuclear spins from the observed resonance spectrum. -- Abstract: We have been developing a novel nuclear laser spectroscopy method “OROCHI” for determining spins and moments of exotic radioisotopes. In this method, we use superfluid helium as a stopping material of energetic radioisotope beams and then stopped radioisotope atoms are subjected to in situ laser spectroscopy in superfluid helium. To confirm the feasibility of this method for rare radioisotopes, we carried out a test experiment using a 85 Rb beam. In this experiment, we have successfully measured the Zeeman resonance signals from the 85 Rb atoms stopped in superfluid helium by laser-RF double resonance spectroscopy. This method is efficient for the measurement of spins and moments of more exotic nuclei

  13. Preface [21. international school on nuclear physics and applications; ISEN-2015: International symposium on exotic nuclei, Varna (Bulgaria), 6-12 September 2015

    International Nuclear Information System (INIS)

    2016-01-01

    The present volume contains the lectures and short talks given at the XXI International School on Nuclear Physics and Applications and International Symposium on Exotic Nuclei (ISEN-2015). The School and the Symposium were held from 6-12 September 2015 in “Club Hotel Bolero” located in ‘Golden Sands’ (Zlatni Pyasaci) Resort on the Black Sea coast, near Varna, Bulgaria. The School and the Symposium were organized by the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences and the Flerov Laboratory of Nuclear Reaction if the Joint Institute for Nuclear Research (Dubna). The co-organizer of the School was the Bulgarian Nuclear Regulatory Agency. According to a long-standing tradition the School has been held biannually since 1973. The School's program has been restructured according to our enlarged new international links and today it is more similar to an international conference than to a classical nuclear physics school. In 2015, the International Symposium on Exotic Nuclei (ISEN-2015) was scheduled from 8-11 September under the auspices of the School. The Symposium was dedicated to the investigation of nuclei in extreme states and, in particular, at the limits of nuclear stability (from very light neutron- and proton-rich up to superheavy nuclei). This new format attracted many young scientists and students from around the world. We had the pleasure of welcoming more than 60 distinguished scientists as lecturers. Additionally, 20 young colleagues received the opportunity to present a short contribution. In all, 90 participants enjoyed the scientific presentations and discussions as well as the relaxing atmosphere at the beach and during the pleasant evenings. The program of the School and the Symposium ranged from the latest results in fundamental areas such as nuclear structure and reactions to frontier issues of the application of nuclear methods. The main topics were the following: Exotic Nuclei and their Properties

  14. Nuclear structure of weakly bound radioactive nuclei through elastic and and inelastic scattering on proton. Impacts of the couplings induced by these exotic nuclei on direct reactions; Structure de noyaux radioactifs faiblement lies par diffusions elastiques et inelastiques sur proton. Effets des couplages induits par ces noyaux exotiques sur les reactions directes

    Energy Technology Data Exchange (ETDEWEB)

    Lapoux, V

    2005-09-15

    Information on the structure, spectroscopy and target interaction potentials of exotic nuclei can be inferred by interpreting measured data from direct reactions on proton such as elastic or inelastic scattering of proton (p,p') or one-nucleon transfer reaction (p,d). A series of experimental results has been obtained at the GANIL facilities on the setting composed of the MUST telescope array used for the detection of light charged-particles and of CATS beam detectors. This setting aims at measuring reactions on light proton or deuteron targets through reverse kinematics. Particularly, results on C{sup 10}, C{sup 11} and on direct reactions with the He{sup 8} beam of Spiral are presented. The first chapter is dedicated to the description of the most important theories concerning the nucleus. The experimental tools used to probe the nucleus are reported in the second chapter. The third and fourth chapters present the framework that has allowed us to analyse results from (p,p') and (p,d) reactions on weakly bound exotic nuclei. The last chapter is dedicated to the description of future experimental programs. (A.C.)

  15. Nuclear structure theory

    CERN Document Server

    Irvine, J M

    1972-01-01

    Nuclear Structure Theory provides a guide to nuclear structure theory. The book is comprised of 23 chapters that are organized into four parts; each part covers an aspect of nuclear structure theory. In the first part, the text discusses the experimentally observed phenomena, which nuclear structure theories need to look into and detail the information that supports those theories. The second part of the book deals with the phenomenological nucleon-nucleon potentials derived from phase shift analysis of nucleon-nucleon scattering. Part III talks about the phenomenological parameters used to de

  16. Time Crystal Platform: From Quasicrystal Structures in Time to Systems with Exotic Interactions

    Science.gov (United States)

    Giergiel, Krzysztof; Miroszewski, Artur; Sacha, Krzysztof

    2018-04-01

    Time crystals are quantum many-body systems that, due to interactions between particles, are able to spontaneously self-organize their motion in a periodic way in time by analogy with the formation of crystalline structures in space in condensed matter physics. In solid state physics properties of space crystals are often investigated with the help of external potentials that are spatially periodic and reflect various crystalline structures. A similar approach can be applied for time crystals, as periodically driven systems constitute counterparts of spatially periodic systems, but in the time domain. Here we show that condensed matter problems ranging from single particles in potentials of quasicrystal structure to many-body systems with exotic long-range interactions can be realized in the time domain with an appropriate periodic driving. Moreover, it is possible to create molecules where atoms are bound together due to destructive interference if the atomic scattering length is modulated in time.

  17. Nuclear Structure Near the Drip Lines

    International Nuclear Information System (INIS)

    Nazarewicz, W.

    1998-01-01

    Experiments with beams of unstable nuclei will make it possible to look closely into many aspects of the nuclear many-body problem. Theoretically, exotic nuclei represent a formidable challenge for the nuclear many-body theories and their power to predict nuclear properties in nuclear terra incognita

  18. Exotic Nuclei and Yukawa's Forces

    International Nuclear Information System (INIS)

    Otsuka, Takaharu; Suzuki, Toshio; Utsuno, Yutaka

    2008-01-01

    In this plenary talk, we will overview the evolution of the shell structure in stable and exotic nuclei as a new paradigm of nuclear structure physics. This shell evolution is primarily due to the tensor force. The robust mechanism and some examples will be presented. Such examples include the disappearance of existing magic numbers and the appearance of new ones. The nuclear magic numbers have been believed, since Mayer and Jensen, to be constants as 2, 8, 20, 28, 50, ... This turned out to be changed, once we entered the regime of exotic nuclei. This shell evolution develops at many places on the nuclear chart in various forms. For example, superheavy magic numbers may be altered. Thus, we are led to a new paradigm as to how and where the nuclear shell evolves, and what consequences arise. The evolution of the shell affects weak process transitions, and plays a crucial role in deformation. The π and ρ mesons generate tensor forces, and are the fundamental elements of such intriguing phenomena. Thus, physics of exotic nuclei arises as a manifestation of Yukawa's forces

  19. Energy exotic options

    International Nuclear Information System (INIS)

    Kaminski, V.; Gibner, S.; Pinnamaneni, K.

    1999-01-01

    This chapter with 88 references focuses on the use of exotic options to control exposure to energy prices. Exotic options are defined, and the conversion of a standard option into an exotic option and pricing models are examined. Pricing and hedging exotic options, path-dependent options, multi-commodity options, options on the minimum-or-maximum of two commodities, compound options, digital options, hybrid and complex structures, and natural gas daily options are described. Formulas for option pricing for vanilla, barrier, compound, options on minimum or maximum of two assets, and look back options are given in an appendix

  20. Component nuclear containment structure

    International Nuclear Information System (INIS)

    Harstead, G.A.

    1979-01-01

    The invention described is intended for use primarily as a nuclear containment structure. Such structures are required to surround the nuclear steam supply system and to contain the effects of breaks in the nuclear steam supply system, or i.e. loss of coolant accidents. Nuclear containment structures are required to withstand internal pressure and temperatures which result from loss of coolant accidents, and to provide for radiation shielding during operation and during the loss of coolant accident, as well as to resist all other applied loads, such as earthquakes. The nuclear containment structure described herein is a composite nuclear containment structure, and is one which structurally combines two previous systems; namely, a steel vessel, and a lined concrete structure. The steel vessel provides strength to resist internal pressure and accommodate temperature increases, the lined concrete structure provides resistance to internal pressure by having a liner which will prevent leakage, and which is in contact with the concrete structure which provides the strength to resist the pressure

  1. Multiquark exotics

    International Nuclear Information System (INIS)

    Lipkin, H.J.

    1983-01-01

    The question Are Anomalons Multiquark Exotics is discussed. It is concluded that so far there is no convincing experimental evidence for any multiquark exotic bound state nor for any exotic resonance. Except for the delta and S* there are no candidates for bound states and no firm theoretical predictions waiting to be tested. Exotic resonances may exist in the 1.5 to 2.0 GeV region and in the charmed sector, e.g., the charmed-strange exotics. The experimental search for multiquark resonances is still open and active

  2. Genetic structure of South African Nguni (Zulu) sheep populations reveals admixture with exotic breeds.

    Science.gov (United States)

    Selepe, Mokhethi Matthews; Ceccobelli, Simone; Lasagna, Emiliano; Kunene, Nokuthula Winfred

    2018-01-01

    The population of Zulu sheep is reported to have declined by 7.4% between 2007 and 2011 due to crossbreeding. There is insufficient information on the genetic diversity of the Zulu sheep populations in the different area of KwaZulu Natal where they are reared. The study investigated genetic variation and genetic structure within and among eight Zulu sheep populations using 26 microsatellite markers. In addition, Damara, Dorper and South African Merino breeds were included to assess the genetic relationship between these breeds and the Zulu sheep. The results showed that there is considerable genetic diversity among the Zulu sheep populations (expected heterozygosity ranging from 0.57 to 0.69) and the level of inbreeding was not remarkable. The structure analysis results revealed that Makhathini Research Station and UNIZULU research station share common genetic structure, while three populations (Nongoma, Ulundi and Nquthu) had some admixture with the exotic Dorper breed. Thus, there is a need for sustainable breeding and conservation programmes to control the gene flow, in order to stop possible genetic dilution of the Zulu sheep.

  3. Genetic structure of South African Nguni (Zulu sheep populations reveals admixture with exotic breeds.

    Directory of Open Access Journals (Sweden)

    Mokhethi Matthews Selepe

    Full Text Available The population of Zulu sheep is reported to have declined by 7.4% between 2007 and 2011 due to crossbreeding. There is insufficient information on the genetic diversity of the Zulu sheep populations in the different area of KwaZulu Natal where they are reared. The study investigated genetic variation and genetic structure within and among eight Zulu sheep populations using 26 microsatellite markers. In addition, Damara, Dorper and South African Merino breeds were included to assess the genetic relationship between these breeds and the Zulu sheep. The results showed that there is considerable genetic diversity among the Zulu sheep populations (expected heterozygosity ranging from 0.57 to 0.69 and the level of inbreeding was not remarkable. The structure analysis results revealed that Makhathini Research Station and UNIZULU research station share common genetic structure, while three populations (Nongoma, Ulundi and Nquthu had some admixture with the exotic Dorper breed. Thus, there is a need for sustainable breeding and conservation programmes to control the gene flow, in order to stop possible genetic dilution of the Zulu sheep.

  4. Nuclear spectroscopy of exotic nuclei with the SARA/IGISOL facility

    International Nuclear Information System (INIS)

    Beraud, R.; Emsallem, A.; Astier, A.; Duffait, R.; Aerje, J.; Aeystoe, J.; Jauho, P.; Barneoud, D.; Genevey, J.; Gizon, A.

    1995-01-01

    Some recent decay studies of neutron-rich and proton-rich nuclei are presented for nuclear structure investigations far off the valley of stability. The experiments, carried out at SARA, are based either on charged particle-induced fission of 238 U or on HI-induced fusion-evaporation reactions in combination with the IGISOL technique. The basic principle of this latter is recalled together with its advantages and limitations. The spectroscopic results obtained in three different regions of the chart of nuclei are sketched. (authors). 30 refs., 7 figs

  5. Concluding Remarks on the International Symposium on Exotic Nuclear Systems ENS'05

    International Nuclear Information System (INIS)

    Habs, D.

    2005-01-01

    In nuclear physics within Europe we observe a strong concentration onto a few large-scale facilities like FAIR, ALICE and EURISOL, which at the same time results in a strong focus of all resources towards these facilities. My personal belief is, that we need in Europe in addition a broad network of smaller institutes with local nuclear physics for a healthy structure of our science. I propose two fields of nuclear science onto which these smaller institutes may focus: (i) Fundamental Physics, studying physics beyond the Standard Model with high precision measurements at low energies and (ii) joining Advanced Photon Science, where new high energy photon and particle beams become available in compact devices at low cost. While such networks are planned or exist already among different universities in Germany for these two subjects, I propose to extend these towards a European networks within the 7th framework. A first starting point could be associations with the German networks, funded by the German Science Foundation DFG

  6. The RIB facility EXOTIC and its experimental program at INFN-LNL

    Science.gov (United States)

    Parascandolo, Concetta

    2018-05-01

    In this contribution, I will present a review about the EXOTIC facility and the research field accessible by using its Radioactive Ion Beams. The EXOTIC facility, installed at the INFN-Laboratori Nazionali di Legnaro, is devoted to the in-flight production of light Radioactive Ion Beams in the energy range between 3-5 MeV/nucleon. The scientific activity performed at EXOTIC concerns different aspects of nuclear physics and nuclear astrophysics, such as, the investigation of reaction mechanisms and nuclear structure, resonant scattering experiments and measurements of nuclear reaction cross sections of astrophysical interest.

  7. Exotic nuclei from a theoretical perspective

    International Nuclear Information System (INIS)

    Nazarewicz, W.; Oak Ridge National Lab., TN; Univ. of Warsaw

    1998-01-01

    One of the main frontiers of nuclear structure today is the physics of radioactive nuclear beams. Experiments with radioactive beams will make it possible to look closely into many aspects of the nuclear many-body problem. What makes this subject both exciting and difficult is: (i) the weak binding and corresponding closeness of the particle continuum, implying a large diffuseness of the nuclear surface and extreme spatial dimensions characterizing the outermost nucleons, and (ii) access to the exotic combinations of proton and neutron numbers which offer prospects for completely new structural phenomena

  8. Nuclear structure studies

    International Nuclear Information System (INIS)

    Walters, W.B.

    1992-01-01

    New results are reported for the decay and nuclear orientation of 114,116 I and 114 Sb as well as data for the structure of daughter nuclides 114,116 Te. New results for IBM-2 calculations for the structure of 126 Xe are also reported. A new approach to the problem of the underproduction of A = 120 nuclides in the astrophysical r-process is reported

  9. Hypernuclei and nuclear structure

    International Nuclear Information System (INIS)

    Rayet, M.

    1977-01-01

    The relations between several aspects of nuclear structure and the Λ hyperon properties inside nuclei are discussed, particularly in connexion with the possibilities offered by the development of new experimental techniques. It is emphasized that Hartree-Fock methods provide an interesting tool for predicting hypernuclear phenomena where the Λ hyperon may be used as a probe of the nucleus [fr

  10. One-nucleon transfer reactions induced by secondary beam of {sup 11}Be: study of the nuclear structure of the exotic nuclei {sup 11}Be and {sup 10}Li; Reactions de transfert d'un nucleon induites par un faisceau secondaire de {sup 11}Be: etude de la structure des noyaux exotiques {sup 11}Be et {sup 10}Li

    Energy Technology Data Exchange (ETDEWEB)

    Pita, S

    2000-09-01

    The structure of the neutron rich light nuclei {sup 11}Be and {sup 10}Li has been investigated by means of one nucleon transfer reactions. The experiments have been carried out at GANIL in inverse kinematics using {sup 11}Be secondary beams. The {sup 11}Be(p,d){sup 10}Be reaction bas been studied at 35.3 MeV/u. The {sup 10}Be ejectiles were analyzed by the spectrometer SPEG, and coincident deuterons were detected in the position sensitive silicon detector CHARISSA. Transfer cross sections to 0{sup +}{sub 1} and 2{sup +}{sub 1}, states in {sup 10}Be were measured up to {theta}{sub CM} = 16 deg. and compared to DWBA and CRC predictions. The effects of neutron-cure couplings on reaction form factors have been studied by solving coupled equations in the framework of a vibrational model. It is shown that the rate of core excitation {sup 10}Be{sub 2+} in the {sup 11}Be{sub gs} wave function is overestimated by a standard analysis with form factors given by the usual Separation Energy prescription. The former model predicts a rate of core excitation of 16% and leads to theoretical cross sections which are in good agreement with the experimental data. The aim of the {sup 11}Be(d,{sup 3}He){sup 10}Li experiment, realized at 37 MeV/u, was to measure the distribution of the 2s neutron strength in the unbound nucleus {sup 10}Li. The energy spectrum was deduced from the {sup 3}He energy and angle measured by the silicon strip detector array MUST. An asymmetric peak is clearly observed near the threshold, with a maximum at -S{sub n} = 130 keV. This constitutes a direct proof of the inversion of 2s and 1p{sub 1/2} shells in {sup 10}Li, which was until now a controversial question in spite of many experimental efforts. On the other band the analysis of the {sup 11}Be(d,t){sup 10}Be reaction studied in the same experiment confirms the results obtained in the {sup 11}Be(p,d){sup 10}Be reaction concerning the {sup 11}Be{sub gs} structure. This work shows the interest and feasibility

  11. Investigation of the halo structure of exotic nuclei by direct reactions in inverse kinematics

    International Nuclear Information System (INIS)

    Egelhof, Peter

    2003-01-01

    Neutron-rich light nuclei near or at the neutron drip line have attracted much attention in recent years since there is clear evidence that they reveal a qualitatively new type of nuclear structure, namely an extended distribution of valence neutrons surrounding a compact nuclear core. A brief overview is given on this halo phenomenon, and on the various methods, which gave first evidence for, and qualitative confirmation of our present picture on halo nuclei

  12. Nuclear structure theory

    International Nuclear Information System (INIS)

    French, J.B.; Koltun, D.S.

    1989-01-01

    This report summarizes progress during the past year in the following areas of research: Pion charge exchange reactions, including a theory of the contribution of pion absorption and correlated double scattering to double charge exchange, new coupled channel calculations for single and double charge exchange from 14 C. Nuclear inelastic scattering, using quark models to calculate nuclear structure functions, and test for sensitivity to the substructure of nucleons in nuclei. Fluctuation-free statistical spectroscopy including the theory and computer programs for interacting-particle densities, spin cutoff factors, occupancies, strength sums, and other expectation values. Proposed research for the coming year in each area is presented

  13. Nuclear structure theory

    International Nuclear Information System (INIS)

    French, J.B.; Koltun, D.S.

    1990-06-01

    This report summarizes progress during the past ten months in the following areas of research: pion double charge exchange reactions, including a theory of the isotensor term in the pion-nucleus optical potential, and a study of meson exchange contributions to the reactions at low energies. Nuclear inelastic scattering, using quark models to calculate nuclear structure functions, and to test for sensitivity to the substructure of nucleons in nuclei. Fluctuation-free statistical spectroscopy including the theory and computer programs for interacting-particle densities, spin cutoff factors, occupancies, strength sums, and other expectation values

  14. Exotic smoothness and particle physics

    International Nuclear Information System (INIS)

    Sladkowski, J.

    1996-01-01

    Short introduction to exotic differential structures on manifolds is given. The possible physical context of this mathematical curiosity is discussed. The topic is very interesting although speculative. (author)

  15. Selected topics in nuclear structure

    International Nuclear Information System (INIS)

    Solov'ev, V.G.; Gromov, K.Ya.; Malov, L.A.; Shilov, V.M.

    1994-01-01

    The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles. heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and β-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei

  16. Selected topics in nuclear structure

    Energy Technology Data Exchange (ETDEWEB)

    Solov` ev, V G; Gromov, K Ya; Malov, L A; Shilov, V M

    1994-12-31

    The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles). heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and {beta}-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei.

  17. Selected topics in nuclear structure

    International Nuclear Information System (INIS)

    1994-01-01

    The collection of abstracts on selected topics in nuclear structure are given. Special attention pays to collective excitations and high-spin states of nuclei, giant resonance structure, nuclear reaction mechanisms and so on

  18. Exotic nuclei

    International Nuclear Information System (INIS)

    Villari, A.C.C.

    1990-01-01

    The actual tendencies to study exotic nuclei; applications of exotic nuclei beams in material study and medicine; recent results obtained by GANIL and Berkeley Laboratories of measurements of binding energy and radii of light nuclei; the future experiences to be carry out in several international laboratories and; proposal of studies in Brazil using Pelletron-USP accelerator and the LINAC superconductor accelerator, in construction in the same laboratory, are presented. (M.C.K.)

  19. Exotic hardrons

    International Nuclear Information System (INIS)

    Landsberg, L.G.

    1994-01-01

    In this review, the present status of the physics of exotic hadrons (mesons and baryons) is considered. It is shown that, that during the last decade, several new meson states were observed, whose properties can hardly be explained in terms of the simple quark model. These particles have become serious candidates for exotic hadrons. The search for narrow, heavy baryons in different production and formation reactions is also discussed. 143 refs., 52 figs., 7 tabs

  20. Relativistic Energy Density Functionals: Exotic modes of excitation

    International Nuclear Information System (INIS)

    Vretenar, D.; Paar, N.; Marketin, T.

    2008-01-01

    The framework of relativistic energy density functionals has been applied to the description of a variety of nuclear structure phenomena, not only in spherical and deformed nuclei along the valley of β-stability, but also in exotic systems with extreme isospin values and close to the particle drip-lines. Dynamical aspects of exotic nuclear structure have been investigated with the relativistic quasiparticle random-phase approximation. We present results for the evolution of low-lying dipole (pygmy) strength in neutron-rich nuclei, and charged-current neutrino-nucleus cross sections.

  1. Nuclear structure of 231Ac

    International Nuclear Information System (INIS)

    Boutami, R.; Borge, M.J.G.; Mach, H.; Kurcewicz, W.; Fraile, L.M.; Gulda, K.; Aas, A.J.; Garcia-Raffi, L.M.; Lovhoiden, G.; Martinez, T.; Rubio, B.; Tain, J.L.; Tengblad, O.

    2008-01-01

    The low-energy structure of 231 Ac has been investigated by means of γ ray spectroscopy following the β - decay of 231 Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a MINI-ORANGE electron spectrometer. The decay scheme of 231 Ra → 231 Ac has been constructed for the first time. The Advanced Time Delayed βγγ(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus

  2. Nuclear spectroscopy of exotic nuclei with the Sara/Igisol facility

    International Nuclear Information System (INIS)

    Beraud, R.; Emsallem, A.; Astier, A.; Duffait, R.; Le Coz, Y.; Redon, N.; Barneoud, D.; Genevey, J.; Gizon, A.

    1994-11-01

    The authors review their recent studies on alpha and beta decay of exotic nuclei performed with the on-line mass separator at the Igisol/Sara facility in Grenoble. The experiments using charged particle induced fission have given new information on production cross section and properties of n-rich nuclei with A=110-130 whereas by means of heavy ion induced fusion evaporation reactions the authors have investigated two regions close to the proton drip line around A=180 and A=130. This paper gives first a brief description of the Igisol technique and shows its application in case of two different production modes: charged particle-induced fission and heavy ion -induced fusion-evaporation reactions. The systematic study of the low-lying levels in n-rich Ru isotopes has allowed to show an axial symmetry breaking, whereas complementary investigations are necessary to clarify the case of 180 Tl decay. A number of new spectroscopic data such as new isotopes identification have been gained in the region of light rare earth nuclei. (N.T.)

  3. Nuclear structure/nuclei far from stability

    International Nuclear Information System (INIS)

    Casten, R.F.; Garrett, J.D.; Moller, P.; Bauer, W.W.; Brenner, D.S.; Butler, G.W.; Crawford, J.E.; Davids, C.N.; Dyer, P.L.; Gregorich, K.; Hagbert, E.G.; Hamilton, W.D.; Harar, S.; Haustein, P.E.; Hayes, A.C.; Hoffman, D.C.; Hsu, H.H.; Madland, D.G.; Myers, W.D.; Penttila, H.T.; Ragnarsson, I.; Reeder, P.L.; Robertson, G.H.; Rowley, N.; Schreiber, F.; Seifert, H.L.; Sherrill, B.M.; Siciliano, E.R.; Sprouse, G.D.; Stephens, F.S.; Subotic, K.; Talbert, W.; Toth, K.S.; Tu, X.L.; Vieira, D.J.; Villari, A.C.C.; Walters, W.B.; Wildenthal, B.H.; Wilhelmy, J.B.; Winger, J.A.; Wohn, F.K.; Wouters, J.M.; Zhou, X.G.; Zhou, Z.Y.

    1990-01-01

    This report outlines some of the nuclear structure topics discussed at the Los Alamos Workshop on the Science of Intense Radioactive Ion Beams (RIB). In it we also tried to convey some of the excitement of the participants for utilizing RIBs in their future research. The introduction of radioactive beams promises to be a major milestone for nuclear structure perhaps even more important than the last such advance in beams based on the advent of heavy-ion accelerators in the 1960's. RIBs not only will allow a vast number of new nuclei to be studies at the extremes of isospin, but the variety of combinations of exotic proton and neutron configurations should lead to entirely new phenomena. A number of these intriguing new studies and the profound consequences that they promise for understanding the structure of the atomic nucleus, nature's only many-body, strongly-inteacting quantum system, are discussed in the preceeding sections. However, as with any scientific frontier, the most interesting phenomena probably will be those that are not anticipated--they will be truly new

  4. Nuclear structure at the proton dripline

    International Nuclear Information System (INIS)

    Maglione, Enrico; Ferreira, Lidia S.; Costa Lopes, Miguel

    2007-01-01

    Recent studies with exotic nuclei far from the stability region, lead to the discovery of one and two proton radioactivity, from ground state of spherical, as well as deformed nuclei. Isomeric decay and fine structure were also measured, and in some cases, a prompt proton and alpha particle emission was observed. It was established that, the majority of prompt particle decays proceeds from superdeformed initial states, into spherical daughter states, revealing a change of deformation during the decay. Proton radioactivity has been the unique way to probe nuclear structure mechanisms in this region of stability. Since proton emitters lie beyond the proton drip-line, they also give the possibility of observing Nilsson resonances. In fact, the experimental data on proton radioactivity in regionswhere theoretical models predict a certain deformation for the nucleus is consistent with the idea that the proton was in a single particle resonance state, in the field of the daughter nucleus. An important aspect of such calculations is the inclusion of the nuclear structure properties of the core,like the rotational spectrum of the daughter nucleus, and the pairing residual interaction. We will address various questions concerning what we have learned from the data and how far our theoretical models have taken us in the region of neutron deficient nuclei at the borders of stability. (Author)

  5. Structure of light mass (exotic) nuclei as evidenced by scattering from hydrogen

    International Nuclear Information System (INIS)

    Amos, K.; Dortmans, P.J.

    1998-01-01

    Microscopic optical model potentials generated by full folding of realistic two-nucleon (n/N) interactions with nuclear structure specified by large basis shell model calculations have been constructed. With those (nonlocal) optical potentials, predictions of light mass nuclei-hydrogen scattering were obtained at intermediate energies (65 to 800 MeV) that agree well with observations of cross sections and analyzing powers

  6. Steel structures for nuclear facilities

    International Nuclear Information System (INIS)

    1993-01-01

    In the guide the requirements concerning design and fabrication of steel structures for nuclear facilities and documents to be submitted to the Finnish Centre for Radiation and Nuclear Safety (STUK) are presented. Furthermore, regulations concerning inspection of steel structures during construction of nuclear facilities and during their operation are set forth

  7. Development of a Tracking System of Exotic Nuclear Beams for FAIR

    International Nuclear Information System (INIS)

    Fernandez, B.; Abou-Haidar, Z.; Alvarez, M. A. G.; Pancin, J.; Drouart, A.; Kebbiri, M.; Riallot, M.

    2010-01-01

    New accelerators like SPIRAL2 (GANIL, France) or FAIR (GSI, Germany) will be soon constructed, and they will be able to produce radioactive ion beams (RIB) with high intensities of current (≥10 6 pps). These beams, at low energy, lower than 20 MeV/n, usually have high emittance, which imposes the use of tracking detectors before the target in order to reconstruct the trajectory of the ions. The group of Nuclear Physics at CNA (Centro Nacional de Aceleradores), is in charge of developing a tracking system for the low energy branch of FAIR (the HISPEC/DESPEC project). A collaboration with CEA-SACLAY was established, with the aim of developing, building and testing low pressure Secondary electron Detectors (SeD). Within this proposal we have projected and constructed a new Nuclear Physics Line in the CNA in order to be able to receive any kind of detector tests and the associated nuclear instruments.

  8. Emission of exotic clusters by nuclei and discovery of a fine structure in the 14C decay of 223Ra

    International Nuclear Information System (INIS)

    Vergnes, M.

    1992-01-01

    This paper is intended as a broad, mainly experimental, survey of the recent field of exotic cluster radioactivity in heavy nuclei. The first part summarizes the development of the field since the first experimental finding in 1984, insisting on 14 C emission, and giving a schematic status of the corresponding models. The second part describes in detail the 1989 discovery, in Orsay, of a fine structure of the 14 C decay of 223 Ra and the search for a similar effect in even-even neighboring nuclei 222 Ra and 224 Ra. A possible qualitative interpretation of the 'hindrance' of the transition to the ground state of 209 Pb is proposed

  9. Emission of exotic clusters by nuclei and discovery of a fine structure in the 14C decay of 223Ra

    International Nuclear Information System (INIS)

    Vergnes, M.

    1992-01-01

    This paper is intended as a broad, mainly experimental, survey of the recent field of exotic cluster radioactivity in heavy nuclei. The first part summarizes the development of the field since the first experimental finding in 1984, insisting on 14 C emission, and giving a schematic status of the corresponding models. The second part describes in detail the 1989 discovery, in Orsay, of a fine structure of the 14 C decay of 223 Ra and the search for a similar effect in even-even neighboring nuclei 222 Ra and 224 Ra. A possible qualitative interpretation of the ''hindrance'' of the transition to the ground state of 209 Pb is proposed

  10. Investigations of Nuclear Structure

    Energy Technology Data Exchange (ETDEWEB)

    Sarantites, Demetrios [Washington Univ., St. Louis, MO (United States); Reviol, W. [Washington Univ., St. Louis, MO (United States)

    2015-07-15

    The proposal addresses studies of nuclear structure at low-energies and development of instrumentation for that purpose. The structure studies deal with features of neutron-rich nuclei with unexplored shapes (football- or pear-shaped nuclei). The regions of interest are: neutron rich nuclei like 132-138Sn, or 48-54Ca, and the Zr, Mo, and Ru isotopes. The tools used can be grouped as follows: either Gammasphere or Gretina multi-gamma detector arrays and auxiliary detectors (Microball, Neutron Shell, and the newly completed Phoswich Wall).The neutron-rich nuclei are accessed by radioactive-beam binary reactions or by 252Cf spontaneous fission. The experiments with heavy radioactive beams aim at exciting the beam nuclei by pick-up or transfer a neutron or a proton from a light target like 13C, 9Be, 11B or 14N .For these binary-reaction studies the Phoswich Wall detector system is essential. It is based on four multi-anode photomultiplier tubes on which CsI and thin fast-timing plastic scintillators are attached. Their signals are digitized with a high density microchip system.

  11. Nuclear Structure References (NSR) file

    International Nuclear Information System (INIS)

    Ewbank, W.B.

    1978-08-01

    The use of the Nuclear Structure References file by the Nuclear Data Project at ORNL is described. Much of the report concerns format information of interest only to those preparing input to the system or otherwise needing detailed knowledge of its internal structure. 17 figures

  12. Nuclear correlations and structure functions

    International Nuclear Information System (INIS)

    Hu Guoju; Irvine, J.M.

    1989-01-01

    It is argued that the search for a mass number dependence of the nuclear structure function per nucleon is profitably directed to the region of Bjorken scaling variable x > 1. We show that in the convolution model of the nuclear structure function the nuclear momentum distribution and energy spectrum generated by cluster expansion techniques, here realised in the correlated basis function method, invoking tensor correlations and short-range density-dependent repulsions adequately describes the structure function for 12 C in the region x > 1. The results of structure functions for a number of light-, medium- and heavy-mass nuclei are presented. (author)

  13. Nuclear structure 1985

    International Nuclear Information System (INIS)

    Broglia, R.; Hagemann, G.; Herskind, B.

    1985-01-01

    These proceedings of the Niels Bohr Centennial Conference contains 40 lectures in nuclear physics ranging over the following subjects: single particle motion; collective motion at low excitation energy; collective motion at high angular momentum; giant resonances and nuclear forces. (G.J.P.)

  14. Exotic nuclei and radioactive beams

    International Nuclear Information System (INIS)

    Chomaz, P.

    1996-01-01

    The Nuclei called exotic are all the nuclei that it is necessary to recreate in laboratory to study them. Their life time is too short -in relation to earth age- for it remains enough on earth. The researchers are going to have at their s disposal at GANIL (Caen) with the S.P.I.R.A.L. project, exotic nuclei beams and will study new kinds of nuclear reactions to better understand the atom nucleus. (N.C.). 2 refs., 9 figs

  15. Exotic Physics

    OpenAIRE

    Sigamani, Michael

    2016-01-01

    A selection of results for searches for exotic physics at the LHC are presented. These include a search for massive resonances, dark matter with a high energy jet in association with large missing transverse momentum, long-lived neutral particles, and narrow dijet resonances. The results are based on 20/fb of LHC proton-proton collisions at sqrt(s) = 8 TeV taken with the CMS detector.

  16. Exotic charmonium

    Energy Technology Data Exchange (ETDEWEB)

    Pakhlova, Galina V; Pakhlov, Pavel N [Alikhanov Institute for Theoretical and Experimental Physics, Russian Federation State Scientific Center, Moscow (Russian Federation); Eidel' man, Semen I [Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2010-06-07

    The most significant results on the spectroscopy, production, and decay of charmonium and charmonium-like states are reviewed. The surprise-filled physics of charmonium is currently attracting great experimental and theoretical attention. Unexpected properties exhibited by numerous discovered states fail to be explained by the theory, which instead suggests the existence in the spectra of charmonium-like particles of exotic systems different from usual bound states. (reviews of topical problems)

  17. Quark effects in nuclear structure

    International Nuclear Information System (INIS)

    Watt, A.

    1987-01-01

    Some experimental data in nuclear structure physics cannot be explained on the assumption that nuclei consist of inert protons and neutrons. The quark model attributes a definite internal structure to nucleons and implies that their properties should change when embedded in a nucleus. This article reviews some of the experimental evidence for these effects and discusses some new aspects of nuclear structure predicted by the quark model

  18. Black Holes and Exotic Spinors

    Directory of Open Access Journals (Sweden)

    J. M. Hoff da Silva

    2016-05-01

    Full Text Available Exotic spin structures are non-trivial liftings, of the orthogonal bundle to the spin bundle, on orientable manifolds that admit spin structures according to the celebrated Geroch theorem. Exotic spin structures play a role of paramount importance in different areas of physics, from quantum field theory, in particular at Planck length scales, to gravity, and in cosmological scales. Here, we introduce an in-depth panorama in this field, providing black hole physics as the fount of spacetime exoticness. Black holes are then studied as the generators of a non-trivial topology that also can correspond to some inequivalent spin structure. Moreover, we investigate exotic spinor fields in this context and the way exotic spinor fields branch new physics. We also calculate the tunneling probability of exotic fermions across a Kerr-Sen black hole, showing that the exotic term does affect the tunneling probability, altering the black hole evaporation rate. Finally we show that it complies with the Hawking temperature universal law.

  19. Exotic power and propulsion concepts

    International Nuclear Information System (INIS)

    Forward, R.L.

    1990-01-01

    The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion

  20. Microscopic description of nuclear structure

    International Nuclear Information System (INIS)

    Girod, M.; Berger, J.F.; Peru, S.; Dancer, H.

    2002-01-01

    After briefly recalling the formalism of the mean field approach with an effective nucleon-nucleon interaction, the theoretical framework of the nuclear structure studies performed at CEA-DAM, applications of this theory to various nuclear systems: shape and spin isomeric states, neutron and proton rich nuclei, superheavy and hyper-heavy nuclei, and to the fission process are presented. (authors)

  1. Relativistic approach to nuclear structure

    International Nuclear Information System (INIS)

    Nguyen Van Giai; Bouyssy, A.

    1987-03-01

    Some recent works related with relativistic models of nuclear structure are briefly reviewed. The Dirac-Hartree-Fock and Dirac-Brueckner-Hartree-Fock are recalled and illustrated by some examples. The problem of isoscalar current and magnetic moments of odd nuclei is discussed. The application of the relativistic model to the nuclear response function is examined

  2. Relativistic models of nuclear structure

    International Nuclear Information System (INIS)

    Gillet, V.; Kim, E.J.; Cauvin, M.; Kohmura, T.; Ohnaka, S.

    1991-01-01

    The introduction of the relativistic field formalism for the description of nuclear structure has improved our understanding of fundamental nuclear mechanisms such as saturation or many body forces. We discuss some of these progresses, both in the semi-classical mean field approximation and in a quantized meson field approach. (author)

  3. Nuclear Structure at the Limits

    International Nuclear Information System (INIS)

    Nazarewicz, W.

    1998-01-01

    One of the frontiers of todays nuclear science is the journey to the limits of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei

  4. Symmetries in nuclear structure

    CERN Document Server

    Allaart, K; Dieperink, A

    1983-01-01

    The 1982 summer school on nuclear physics, organized by the Nuclear Physics Division of the Netherlands' Physical Society, was the fifth in a series that started in 1963. The number of students attending has always been about one hundred, coming from about thirty countries. The theme of this year's school was symmetry in nuclear physics. This book covers the material presented by the enthusi­ astic speakers, who were invited to lecture on this subject. We think they have succeeded in presenting us with clear and thorough introductory talks at graduate or higher level. The time schedule of the school and the location allowed the participants to make many informal contacts during many social activities, ranging from billiards to surf board sailing. We hope and expect that the combination of a relaxed atmosphere during part of the time and hard work during most of the time, has furthered the interest in, and understanding of, nuclear physics. The organization of the summer school was made possible by substantia...

  5. Concrete structures for nuclear facilities

    International Nuclear Information System (INIS)

    1996-01-01

    The detailed requirements for the design and fabrication of the concrete structures for nuclear facilities and for the documents to be submitted to the Finnish Centre for Radiation and Nuclear Safety (STUK) are given in the guide. It also sets the requirements for the inspection of concrete structures during the construction and operation of facilities. The requirements of the guide primarily apply to new construction. As regards the repair and modification of nuclear facilities built before its publication, the guide is followed to the extent appropriate. The regulatory activities of the Finnish Centre for Radiation and Nuclear Safety during a nuclear facility's licence application review and during the construction and operation of the facility are summarised in the guide YVL 1.1

  6. The Nucleus 59Cu. Complex Structure, Shape Evolution, Exotic Decay Modes

    International Nuclear Information System (INIS)

    Andreoiu, Corina

    2002-08-01

    High-spin states in the mass A∼60 region were populated using the state-of-art γ-ray spectrometers Gammasphere, Euroball, and GASP in conjunction with dedicated ancillary detectors. In particular, the 59 Cu nucleus was studied in several experiments, and a very extensive level scheme was determined. It comprises more than 320 transitions connecting about 150 excited states. Relative to mass, it is the most extensive level scheme known to date. Next to the spherical states at low excitation energy eight regular sequences of high-energy γ-ray transitions have been observed. They form rotational bands with various degree of deformation, which are interpreted in the light of the shell model and the configuration-dependent Cranked Nilsson-Strutinsky approach. One of the experiments was dedicated to the study of prompt particle decays. It revealed five prompt proton decays connecting five deformed states in three of the rotational bands in 59 Cu with three spherical states in the daughter nucleus 58 Ni. It is the first observation of the fine structure of the newly discovered prompt proton decay mode. The proton decays compete with the γ decay-out from the second minimum of the nuclear potential into the low-spin spherical states in the first minimum of the potential. The discrete γ decay-out mechanism of the yrast superdeformed band is investigated in detail. The nucleus 59 Zn, the mirror partner of 59 Cu, was identified for the first time, and the mirror symmetry of the T=1/2 A=59 pair is discussed

  7. Selected topics in nuclear structure

    International Nuclear Information System (INIS)

    Faessler, A.

    1990-01-01

    Today's dream of nuclear structure physics is to calculate the properties of nuclei starting from Quantum-Chromodynamics (QCD). However, we are definitely not able to do that today and may be even in the future one would wish only to show in principle that this is possible. It probably will never be a daily approach to study excitation energies, transitions probabilities and other properties of nuclei. This paper discusses the possibility of coming from the shore of QCD to the other side of the river, to nuclear structure, not in one great arch buy like medieval bridges in several arches grounded each solidly on pillars going down to the river floor and by that connecting theory with the solid ground of experiments. The first arch is meant to connect QCD and the nucleon-nucleon phase shifts with the help to the nucleon-nucleon phase shifts with the experimentally fitted effective interactions for the final model spaces used in nuclear structure calculations. This is at the moment still by far the weakest arch although a large amount of work and ideas have been invested since about the middle of the 60's to derive a theory of effective interactions and to establish the connection of the effective interaction fitted to nuclear structure data with the bare interaction between nucleons in the vacuum. The last arch is connecting the effective nucleon-nucleon interaction with nuclear structure properties

  8. Nuclear structure from radioactive decay

    International Nuclear Information System (INIS)

    Wood, J.L.

    1991-01-01

    This report discusses nuclear structure from radioactive decay of the following: Neutron-Deficient Iridium Isotopes; Neutron-Deficient Platinum Isotopes; Neutron-Deficient Gold Isotopes; Neutron-Deficient Mercury Isotopes; Neutron-Deficient Thallium Isotopes; Neutron-Deficient Lead Isotopes; Neutron-Deficient Samarium Isotopes; Neutron-Deficient Promethium Isotopes; Neutron-Deficient Neodymium Isotopes; and Neutron-Deficient Praseodymium Isotopes. Also discussed are Nuclear Systematics and Models

  9. Euroschool on Exotic Beams

    CERN Document Server

    Pfützner, Marek

    2018-01-01

    This is the fifth volume in a series of Lecture Notes based on the highly successful Euro Summer School on Exotic Beams. The aim of these notes is to provide a thorough introduction to radioactive ion-beam physics at the level of graduate students and young postdocs starting out in the field. Each volume covers a range of topics from nuclear theory to experiment and applications. Vol I has been published as LNP 651, Vol II as LNP 700, Vol. III as LNP 764 and Vol. IV as LNP 879.

  10. Low-lying states and structure of the exotic 8He via direct reactions on the proton

    International Nuclear Information System (INIS)

    Skaza, F.; Lapoux, V.; Keeley, N.; Alamanos, N.; Auger, F.; Beaumel, D.; Becheva, E.; Blumenfeld, Y.; Delaunay, F.; Drouart, A.; Gillibert, A.; Giot, L.; Khan, E.; Nalpas, L.; Pakou, A.; Pollacco, E.; Raabe, R.; Roussel-Chomaz, P.; Rusek, K.; Scarpaci, J.-A.; Sida, J.-L.; Stepantsov, S.; Wolski, R.

    2007-01-01

    The structure of the light exotic nucleus 8 He was investigated using direct reactions of the 8 He SPIRAL beam on a proton-rich target. The (p,p') scattering to the 2 1 + state, the (p,d) 7 He and (p,t) 6 He transfer reactions, were measured at the energy E lab =15.7 A.MeV. The light charged particles (p,d,t) were detected in the MUST Si-strip telescope array. The excitation spectrum of 8 He was extracted from the (p,p') reaction. Above the known 2 1 + excited state at 3.6 MeV, a second resonance was found around 5.4 MeV. The cross sections were analyzed within the coupled-reaction channels framework, using microscopic potentials. It is inferred that the 8 He ground state has a more complex neutron-skin structure than suggested by previous α+4n models assuming a pure (1p 3/2 ) 4 configuration

  11. Theoretical studies in nuclear reactions and nuclear structure

    International Nuclear Information System (INIS)

    Wallace, S.J.

    1991-05-01

    This report discusses topics in the following areas: Hadronic structure; hadrons in nuclei; hot hadronic matter; relativistic nuclear physics and NN interaction; leptonic emissions from high-Z heavy ion collisions; theoretical studies of heavy ion dynamics; nuclear pre-equilibrium reactions; classical chaotic dynamics and nuclear structure; and, theory of nuclear fission

  12. Electron scattering and nuclear structure

    International Nuclear Information System (INIS)

    Frois, B.

    1987-01-01

    The search for the appropriate degrees of freedom to describe nuclei is the central focus of nuclear physics today. Therefore the authors explore in this review their current understanding of nuclear structure as defined by electromagnetic data. The precision of the electromagnetic probe allows us to define accurately the limits of present theoretical descriptions. The authors review here a broad range of subjects that have been addressed by recent experiments, from the study of meson exchange currents and single-particle distributions to collective excitations in heavy nuclei. However, they do not discuss elastic magnetic scattering, inelastic excitation of discrete states, or single-nucleon knockout reactions since these reactions were recently reviewed. The principal aim of this review is to offer a fresh perspective on nuclear structure, based on the new generation of electron scattering data presented here and in the above-mentioned articles

  13. Nuclear Structure Research at TRIUMF

    Science.gov (United States)

    Garrett, P. E.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Chakrawarthy, R. S.; Cline, D.; Cooper, R. J.; Churchman, R.; Cross, D.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T. E.; Finlay, P.; Gagon-Miosan, F.; Gallant, A. T.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Hackman, G.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Kulp, W. D.; Leach, K. G.; Lee, G.; Leslie, J. R.; Martin, J.-P.; Mattoon, C.; Mills, W. J.; Morton, A. C.; Mythili, S.; Nelson, L.; Newman, O.; Nolan, P. J.; Padilla-Rodal, E.; Pearson, C. J.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Roy, R.; Ruiz, C.; Savajols, H.; Sarazin, F.; Schumaker, M. A.; Scraggs, D. P.; Scraggs, H. C.; Strange, M. D.; Svensson, C. E.; Waddington, J. C.; Wan, J. M.; Whitbeck, A.; Williams, S. J.; Wong, J.; Wood, J. L.; Wu, C. Y.; Zganjar, E. F.

    2007-04-01

    The radioactive beam laboratory at TRIUMF is currently the highest power ISOL facility in the world. Taking advantage of the high-intensity beams, major programs in nuclear astrophysics, nuclear structure, and weak interaction studies have begun. The low-energy area, ISAC-I, is capable of delivering beams up to mass 30 at approx 1.7 MeV/u or 60 keV up to the mass of the primary target, whereas ISAC-II will ultimately provide beams up to mass 150 and approx 6.5 MeV/u. Major gamma -ray spectrometers for nuclear structure research consist of the 8pi spectrometer at ISAC-I, and the TIGRESS spectrometer now being constructed for ISAC-II. Results from recent experiments investigating the beta -decay of nuclei near N=90 and Coulomb excitation of 20,21Na are presented that highlight the capabilities of the spectrometers.

  14. Structural analysis of nuclear components

    International Nuclear Information System (INIS)

    Ikonen, K.; Hyppoenen, P.; Mikkola, T.; Noro, H.; Raiko, H.; Salminen, P.; Talja, H.

    1983-05-01

    THe report describes the activities accomplished in the project 'Structural Analysis Project of Nuclear Power Plant Components' during the years 1974-1982 in the Nuclear Engineering Laboratory at the Technical Research Centre of Finland. The objective of the project has been to develop Finnish expertise in structural mechanics related to nuclear engineering. The report describes the starting point of the research work, the organization of the project and the research activities on various subareas. Further the work done with computer codes is described and also the problems which the developed expertise has been applied to. Finally, the diploma works, publications and work reports, which are mainly in Finnish, are listed to give a view of the content of the project. (author)

  15. Laser measurements and nuclear structure

    International Nuclear Information System (INIS)

    Leander, G.A.

    1982-01-01

    The nuclear states amenable to laser studies are reviewed with respect to their structure. Systematic predictions are made, e.g., for magnetic moments of parity-mixed intrinsic orbitals in the Ac isotopes and for the shape of the known high-spin isomers in the Pb region

  16. Selected topics in nuclear structure

    International Nuclear Information System (INIS)

    Stachura, Z.

    1984-09-01

    19. winter school in Zakopane was devoted to selected topics in nuclear structure such as: production of spin resonances, heavy ions reactions and their applications to the investigation of high spin states, octupole deformations, excited states and production of new elements etc. The experimental data are ofen compared with theoretical predictions. Report contains 28 papers. (M.F.W.)

  17. Underwater nuclear power plant structure

    International Nuclear Information System (INIS)

    Severs, S.; Toll, H.V.

    1982-01-01

    A structure for an underwater nuclear power generating plant comprising a triangular platform formed of tubular leg and truss members upon which are attached one or more large spherical pressure vessels and one or more small cylindrical auxiliary pressure vessels. (author)

  18. Probing nuclear structure with nucleons

    International Nuclear Information System (INIS)

    Bauge, E.

    2007-01-01

    The goal of this lecture is to show how nucleon scattering can be used to probe the structure of target nuclei, and how nucleon scattering observables can be interpreted in terms of nuclear structure using microscopic optical potentials. After a brief overview of the specificities of nucleon-nucleus scattering, and a quick reminder on scattering theory, the main part of this lecture is devoted to the construction of optical potentials in which the target nuclei structure information is folded with an effective interaction. Several examples of such microscopic optical model potentials are given. (author)

  19. Problems of structural mechanics in nuclear design

    International Nuclear Information System (INIS)

    Patwardhan, V.M.; Kakodkar, Anil

    1975-01-01

    A very careful and detailed stress analysis of nuclear presure vessels and components is essential for ensuring the safety and integrity of nuclear power plants. The nuclear designer, therefore, relies heavily on structural mechanics for application of the most advanced stress analysis techniques to practical design problems. The paper reviews the inter-relation between structural mechanics and nuclear design and discusses a few of the specific structural mechanics problems faced by the nuclear designers in the Department of Atomic Energy, India. (author)

  20. Nuclear structure with coherent states

    CERN Document Server

    Raduta, Apolodor Aristotel

    2015-01-01

    This book covers the essential features of a large variety of nuclear structure properties, both collective and microscopic in nature. Most of results are given in an analytical form thus giving deep insight into the relevant phenomena. Using coherent states as variational states, which allows a description in the classical phase space, or provides the generating function for a boson basis, is an efficient tool to account, in a realistic fashion, for many complex properties. A detailed comparison with all existing nuclear structure models provides readers with a proper framework and, at the same time, demonstrates the prospects for new developments. The topics addressed are very much of current concern in the field. The book will appeal to practicing researchers and, due to its self-contained account, can also be successfully read and used by new graduate students.

  1. Book of abstracts of International Conference on Nuclear Structure and Dynamics 2009

    International Nuclear Information System (INIS)

    Prepolec, L.; Niksic, T.

    2009-01-01

    Following the long tradition of nuclear physics conferences organized by our two institutes, e.g. the Adriatic International Conference and Europhysics Study Conferences, this meeting will provide a broad discussion forum on recent experimental and theoretical advances in the physics of nuclear structure and reactions. The main focus will be on the following topics: Nuclear structure and reactions far from stability; Exotic modes of excitation and decays; Collective phenomena and symmetries; Ab initio, cluster model, and shell-model approaches; Nuclear energy density functionals; Heavy-ion reactions at near-barrier energies; Dynamics of light-ion reactions; Nuclear reactions of astrophysical interest; Weak-interaction processes. This booklet contains the abstracts of contributions which will be presented at the Conference, either as invited and contributed talks, or oral poster presentations

  2. Nuclear structure references coding manual

    International Nuclear Information System (INIS)

    Ramavataram, S.; Dunford, C.L.

    1984-02-01

    This manual is intended as a guide to Nuclear Structure References (NSR) compilers. The basic conventions followed at the National Nuclear Data Center (NNDC), which are compatible with the maintenance and updating of and retrieval from the Nuclear Structure References (NSR) file, are outlined. The structure of the NSR file such as the valid record identifiers, record contents, text fields as well as the major topics for which [KEYWORDS] are prepared are ennumerated. Relevant comments regarding a new entry into the NSR file, assignment of [KEYNO ], generation of [SELECTRS] and linkage characteristics are also given. A brief definition of the Keyword abstract is given followed by specific examples; for each TOPIC, the criteria for inclusion of an article as an entry into the NSR file as well as coding procedures are described. Authors submitting articles to Journals which require Keyword abstracts should follow the illustrations. The scope of the literature covered at NNDC, the categorization into Primary and Secondary sources, etc. is discussed. Useful information regarding permitted character sets, recommended abbreviations, etc. is given

  3. Exotic superdeformed structure in A∼190 nuclei observed using Eurogam2

    International Nuclear Information System (INIS)

    Wilson, A.N.; Timar, J.; Bergstroem, M.; Paul, E.S.; Bouneau, S.; Azaiez, F.; Korichi, A.; Nakatsukasa, T.

    1995-01-01

    Dipole transitions between superdeformed rotational bands are only very rarely observed due to the competition from the very strong in-band E2 decays. We have carried out two experiments with the EUROGAM2 γ-ray spectrometer, situated at the Vivitron tandem accelerator at CRN Strasbourg, in September and October 1994. In the first experiment we observe M1 dipole transitions between the signature partner yrast superdeformed bands in 193 Tl. This measurement gives a mean value of (g K -g R ) K/Q o = 0.135 ± 0.010 μ N /eb identifying the bands as belonging to the (642)5/2 single particle orbital. We also observe 5 additional new superdeformed bands in 193 Tl, whose structures are discussed. In the second experiment we observe three transitions, at 911, 865 and 831 keV, which link an excited superdeformed band in 190 Hg to the yrast superdeformed band. The data suggest that these are stretched dipole transitions with E1 multipolarity and strengths of about 10 -3 Wu. This is the first observation of a collective vibration of the superdeformed mean field. We also observe two new superdeformed bands in 190 Hg. (authors). 39 refs., 11 figs., 3 tabs

  4. Nuclear Power Plant Concrete Structures

    Energy Technology Data Exchange (ETDEWEB)

    Basu, Prabir [International Atomic Energy Agency (IAEA); Labbe, Pierre [Electricity of France (EDF); Naus, Dan [Oak Ridge National Laboratory (ORNL)

    2013-01-01

    A nuclear power plant (NPP) involves complex engineering structures that are significant items of the structures, systems and components (SSC) important to the safe and reliable operation of the NPP. Concrete is the commonly used civil engineering construction material in the nuclear industry because of a number of advantageous properties. The NPP concrete structures underwent a great degree of evolution, since the commissioning of first NPP in early 1960. The increasing concern with time related to safety of the public and environment, and degradation of concrete structures due to ageing related phenomena are the driving forces for such evolution. The concrete technology underwent rapid development with the advent of chemical admixtures of plasticizer/super plasticizer category as well as viscosity modifiers and mineral admixtures like fly ash and silica fume. Application of high performance concrete (HPC) developed with chemical and mineral admixtures has been witnessed in the construction of NPP structures. Along with the beneficial effect, the use of admixtures in concrete has posed a number of challenges as well in design and construction. This along with the prospect of continuing operation beyond design life, especially after 60 years, the impact of extreme natural events ( as in the case of Fukushima NPP accident) and human induced events (e.g. commercial aircraft crash like the event of September 11th 2001) has led to further development in the area of NPP concrete structures. The present paper aims at providing an account of evolution of NPP concrete structures in last two decades by summarizing the development in the areas of concrete technology, design methodology and construction techniques, maintenance and ageing management of concrete structures.

  5. Food web structure in exotic and native mangroves: A Hawaii-Puerto Rico comparison

    Science.gov (United States)

    Demopoulos, A.W.J.; Fry, B.; Smith, C.R.

    2007-01-01

    Plant invasions can fundamentally alter detrital inputs and the structure of detritus-based food webs. We examined the detrital pathways in mangrove food webs in native (Puerto Rican) and introduced (Hawaiian) Rhizophora mangle forests using a dual isotope approach and a mixing model. Based on trophic-level fractionation of 0-1??? for ?? 13C and 2-3??? for ?? 15N, among the invertebrates, only nematodes, oligochaetes, and nereid polychaetes from native mangroves exhibited stable isotopes consistent with a mangrove-derived diet. Certain fauna, in particular tubificid oligochaetes, had ?? 13C values consistent with the consumption of mangrove leaves, but they were depleted in 15N, suggesting their primary nitrogen source was low in 15N, and was possibly N 2-fixing bacteria. In introduced mangroves, all feeding groups appeared to rely heavily on non-mangrove sources, especially phytoplankton inputs. Mixing model results and discriminant analysis showed clear separation of introduced and native mangrove sites based on differential food source utilization within feeding groups, with stronger and more diverse use of benthic foods observed in native forests. Observed differences between native and invasive mangrove food webs may be due to Hawaiian detritivores being poorly adapted to utilizing the tannin-rich, nitrogen-poor mangrove detritus. In addition, differential utilization of mangrove detritus between native and introduced mangroves may be a consequence of forest age. We postulate that increasing mangrove forest age may promote diversification of bacterial food webs important in N and S cycling. Our results also suggest a potentially important role for sulfur bacteria in supporting the most abundant infaunal consumers, nematodes, in the most mature systems. ?? 2007 Springer-Verlag.

  6. Studying the Atomic Nucleus - A New Era in Nuclear Structure Studies

    International Nuclear Information System (INIS)

    Casten, R. F.

    2011-01-01

    The study of atomic nuclei is part of the fascinating quest to understand the fundamental nature and origins of matter. This field, nuclear structure, is undergoing a revolutionary transformation that is breaking cherished paradigms, opening new vistas of nuclear matter for study, and which has the promise of leading to a new comprehensive understanding. The advent of new facilities for the production and study of exotic nuclei provides access to an entirely new territory of nuclei, and advances in extreme computing are enabling similar advances in the theory of atomic nuclei.

  7. Stocked exotic predators and their interaction with native galaxiids (Pisces: Galaxiidae) shape the food web structure in Tasmanian lakes

    DEFF Research Database (Denmark)

    Vidal, Nicolas; Amsinck, Susanne Lildal; Barmuta, Leon

    2015-01-01

    maximum body size, but not of cladocerans. The zooplankton community food web was wider in lakes with lower pelagic contribution to the fish diet. Our results suggest a negative effect by exotic predators on the niche width of galaxiids, but weak cascading effects on phytoplankton biomass, and a negative...

  8. Nuclear structure of {sup 231}Ac

    Energy Technology Data Exchange (ETDEWEB)

    Boutami, R. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); Borge, M.J.G. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain)], E-mail: borge@iem.cfmac.csic.es; Mach, H. [Department of Radiation Sciences, ISV, Uppsala University, SE-751 21 Uppsala (Sweden); Kurcewicz, W. [Department of Physics, University of Warsaw, Pl-00 681 Warsaw (Poland); Fraile, L.M. [Departamento Fisica Atomica, Molecular y Nuclear, Facultad CC. Fisicas, Universidad Complutense, E-28040 Madrid (Spain); ISOLDE, PH Department, CERN, CH-1211 Geneva 23 (Switzerland); Gulda, K. [Department of Physics, University of Warsaw, Pl-00 681 Warsaw (Poland); Aas, A.J. [Department of Chemistry, University of Oslo, PO Box 1033, Blindern, N-0315 Oslo (Norway); Garcia-Raffi, L.M. [Instituto de Fisica Corpuscular, CSIC - Universidad de Valencia, Apdo. 22805, E-46071 Valencia (Spain); Lovhoiden, G. [Department of Physics, University of Oslo, PO Box 1048, Blindern, N-0316 Oslo (Norway); Martinez, T.; Rubio, B.; Tain, J.L. [Instituto de Fisica Corpuscular, CSIC - Universidad de Valencia, Apdo. 22805, E-46071 Valencia (Spain); Tengblad, O. [Instituto de Estructura de la Materia, CSIC, Serrano 113 bis, E-28006 Madrid (Spain); ISOLDE, PH Department, CERN, CH-1211 Geneva 23 (Switzerland)

    2008-10-15

    The low-energy structure of {sup 231}Ac has been investigated by means of {gamma} ray spectroscopy following the {beta}{sup -} decay of {sup 231}Ra. Multipolarities of 28 transitions have been established by measuring conversion electrons with a MINI-ORANGE electron spectrometer. The decay scheme of {sup 231}Ra {yields}{sup 231}Ac has been constructed for the first time. The Advanced Time Delayed {beta}{gamma}{gamma}(t) method has been used to measure the half-lives of five levels. The moderately fast B(E1) transition rates derived suggest that the octupole effects, albeit weak, are still present in this exotic nucleus.

  9. Symmetries of the nuclear average field hamiltonian and a search for possible exotic equilibrium deformations in superdeformed nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Li Xunjun; Dudek, J.; Romain, P. (Centre de Recherches Nucleaires, IN2P3-CNRS, Univ. Louis Pasteur, 67 - Strasbourg (France))

    1991-11-21

    Symmetry properties of the general average-field hamiltonian-matrix resulting from the geometrical symmetries of the hamiltonian itself are derived and discussed. The corresponding numerical algorithms are constructed. Total energy calculations for superdeformed nuclei are then extended to include the usually neglected deformation modes {alpha}{sub {lambda}=3{mu}{ne}0} in the expansion of the nuclear surface expression R({theta}, {phi}; {l brace}{alpha}{r brace})=c({l brace}{alpha}{r brace})R{sub 0}(1+{Sigma}{sub {lambda}} {Sigma}{sub {mu}=-{lambda}}{sup {lambda}} {alpha}{sub {lambda}{mu}}{sup *}{Upsilon}{sub {lambda}{mu}}({theta}, {phi})). The general trends in the shell-energy dependence on {alpha}{sub {lambda}=3{mu}} and the implied instabilities in the superdeformed configurations of the rare earth nuclei are studied using the Strutinsky formula with the macroscopic part taken in the form of the folded-Yukawa plus exponential interaction. A possibility of new (double superdeformed minimum) structures coexisting in some nuclei and resulting from the proton shell effects is predicted and illustrated. No significant neutron effects are found in the rare earth superdeformed nuclei considered. (orig.).

  10. Exotic superconductors

    International Nuclear Information System (INIS)

    Balibar, S.

    1984-01-01

    UBe 13 hesitates, at low temperature, between two types of structure together antagonists and complementary: antiferromagnetism and superconductivity. Moreover, the last one seems a new kind of superconductivity. The alloy properties are recalled and debatable points are examined [fr

  11. Statistical aspects of nuclear structure

    International Nuclear Information System (INIS)

    Parikh, J.C.

    1977-01-01

    The statistical properties of energy levels and a statistical approach to transition strengths are discussed in relation to nuclear structure studies at high excitation energies. It is shown that the calculations can be extended to the ground state domain also. The discussion is based on the study of random matrix theory of level density and level spacings, using the Gaussian Orthogonal Ensemble (GOE) concept. The short range and long range correlations are also studied statistically. The polynomial expansion method is used to obtain excitation strengths. (A.K.)

  12. PREFACE: Open Problems in Nuclear Structure Theory: Introduction Open Problems in Nuclear Structure Theory: Introduction

    Science.gov (United States)

    Dobaczewski, Jacek

    2010-06-01

    Nuclear structure theory is a domain of physics faced at present with great challenges and opportunities. A larger and larger body of high-precision experimental data has been and continues to be accumulated. Experiments on very exotic short-lived isotopes are the backbone of activity at numerous large-scale facilities. Over the years, tremendous progress has been made in understanding the basic features of nuclei. However, the theoretical description of nuclear systems is still far from being complete and is often not very precise. Many questions, both basic and practical, remain unanswered. The goal of publishing this special focus issue of Journal of Physics G: Nuclear and Particle Physics on Open Problems in Nuclear Structure Theory (OPeNST) is to construct a fundamental inventory thereof, so that the tasks and available options become more clearly exposed and that this will help to stimulate a boost in theoretical activity, commensurate with the experimental progress. The requested format and scope of the articles on OPeNST was quite flexible. The journal simply offered the possibility to provide a forum for the material, which is very often discussed at conferences during the coffee breaks but does not normally have sufficient substance to form regular publications. Nonetheless, very often formulating a problem provides a major step towards its solution, and it may constitute a scientific achievement on its own. Prospective authors were therefore invited to find their own balance between the two extremes of very general problems on the one hand (for example, to solve exactly the many-body equations for a hundred particles) and very specific problems on the other hand (for example, those that one could put in one's own grant proposal). The authors were also asked not to cover results already obtained, nor to limit their presentations to giving a review of the subject, although some elements of those could be included to properly introduce the subject matter

  13. ENSDF: a nuclear structure data bank for nuclear physicists

    International Nuclear Information System (INIS)

    Blachot, J.

    1987-02-01

    Data Banks have tremendously grown these last years. All the nuclear Structure information are now in the ENSDF. This file is used for the Nuclear Data Sheets publication. The part which contains only Adopted Data could be used as a Data Bank for Nuclear Physicists. Examples of retrevial are given [fr

  14. Annual report of the Nuclear Structure Committee

    International Nuclear Information System (INIS)

    1977-01-01

    The Annual Report for the period 1 August 1975 to 31 July 1976 of the Nuclear Structure Committee of the Nuclear Physics Board, under the (United Kingdom) Science Research Council, is presented. Details are given of nuclear structure grants and laboratory agreements. (U.K.)

  15. Trends in exotic-atom research

    International Nuclear Information System (INIS)

    Lambrecht, R.M.; Horvath, D.

    1983-01-01

    An attempt was made to analyze the trends in the development of exotic-atom research on the basis of a recently compiled bibliography. The analysis of nearly 4000 publications demonstrated that: (1) exotic atoms are nuclear probes used in every field of physics, from the test of quantum electrodynamics (QED) to chemical physics, to materials sciences; (2) the role of nuclear and atomic physics in exotic atom research is decreasing (although it is still significant), while that of materials sciences and chemial physics is exponentially increasing; and (3) prior to 1980 most investigators were mainly interested in atoms with negative muons, while during the last few years the positive muon (μSR) studies have dominated exotic atom research

  16. Nuclear structure at intermediate energies

    International Nuclear Information System (INIS)

    Bonner, B.E.; Mutchler, G.S.

    1989-01-01

    This paper discusses the following topics: Σdegree C Spin Transfer Experiment; Strangeness Production in Heavy Ion Collisions; Search for a J PC Exotic Hybrid Meson; Antiproton-Nucleus Interactions; Single Pion Production in np Scattering; Two-and Three-Spin Measurements in pp-pp; Proton-Deuteron Elastic Scattering at 800 MeV Two- and Three-Spin Observables; pp Elastic Absolute Cross-Section Measurements; Single Pion Production in np Scattering; Photojets from Nuclei; CCD Development; Computer Acquisition and Computer Software

  17. Nuclear structure at intermediate energies

    International Nuclear Information System (INIS)

    Bonner, B.E.; Mutchler, G.S.

    1990-01-01

    This paper discusses the following topics: antiproton nucleus interactions; strangeness production in heavy ion collisions; search for a J PC exotic hybrid meson; the SMC experiment; pion production in rvec np scattering; spin transfer measurements for rvec np elastic scattering; pion production in rvec n rvec p scattering; radiative muon capture (RMC) on hydrogen; radiative decays of low-lying hyperons; photoproduction of jets in nuclei; cylindrical multiplicity detector; MWPC detectors and electronics; lead glass array; cylindrical wire chamber; beam calorimeter; shower counter; and muon veto hodoscope

  18. Direct reactions in inverse kinematics for nuclear structure studies far off stability at low incident energies

    International Nuclear Information System (INIS)

    Egelhof, P.

    1997-02-01

    The investigation of light-ion induced direct reactions with exotic beams in inverse kinematics gives access to a wide field of nuclear structure studies in the region far off stability. The present contribution will focus on the investigation of few-nucleon transfer reactions, which turn out to be most favourably studied with good-quality low-energy radioactive beams, as provided by the new generation of radioactive beam facilities presently planned or under construction at Caen, Grenoble, Munich, and elsewhere. An overview on the physics motivation, basically concerning nuclear structure and nuclear astrophysics questions, is given. Of particular interest are the nuclear shell model in the region far off stability, the two-body residual interaction in nuclei, the structure of halo nuclei, as well as the understanding of the r-process scenario. The experimental conditions, along with the experimental concept, for such measurements are discussed with particular emphasis on the kinematical conditions, the observables, as well as the appropriate detection schemes. The concept of a large solid angle TPC ionization chamber as an active target for experiments with low-energy radioactive beams is presented. It turns out to be a highly effective detection scheme, well suited for the present experimental conditions, at least for light exotic beams up to Z∼20. (orig.)

  19. Selected topic in nuclear structure. V. 1

    International Nuclear Information System (INIS)

    Broda, R.; Stachura, Z.; Styczen, J.

    1985-01-01

    A report of recent experiments performed in different laboratories and a review of fundamental problems of nuclear physics connected with study of nuclear structure, that had just been solved are presented. The proceedings contain 33 articles. (M.F.-W.)

  20. Dipole rescattering and the nuclear structure function

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, F. [Depto de Ciencias Exatas e da Terra, Universidade Federal de Sao Paulo, SP (Brazil); Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-900, Pelotas, RS (Brazil); Navarra, F. S.; Oliveira, E. G. [Instituto de Fisica, Universidade de Sao Paulo Rua do Matao, Travessa R, 187, 05508-090 Sao Paulo, SP (Brazil)

    2013-03-25

    In the framework of the dipole model, we study the effects of the dipole multiple scatterings in a nuclear target and compute the nuclear structure function. We compare different unitarization schemes and confront our results with the E665 data.

  1. Interfaces of nuclear structure studies-decay vs. in-beam experiments

    International Nuclear Information System (INIS)

    Grawe, H.; Gorska, M.; Hu, Z.; Roeckl, E.; Lipoglavsek, M.; Fahlander, C.; Rykaczewski, K.

    1999-05-01

    The common interface of β-decay and particle-decay experiments and in-beam studies following fusion, relativistic fission and projectile fragmentation is defined by the search for the best way to extract nuclear structure information. For a few examples selected from the exotic regions of nuclei around 100 Sn and between 68 Ni and 78 Ni it is demonstrated, that complementary spectroscopic data extracted by various methods lead to an understanding of the shell structure at these keypoints of the nuclidic chart. (orig.)

  2. Non-empirical energy density functional for the nuclear structure

    International Nuclear Information System (INIS)

    Rot ival, V.

    2008-09-01

    The energy density functional (EDF) formalism is the tool of choice for large-scale low-energy nuclear structure calculations both for stable experimentally known nuclei whose properties are accurately reproduced and systems that are only theoretically predicted. We highlight in the present dissertation the capability of EDF methods to tackle exotic phenomena appearing at the very limits of stability, that is the formation of nuclear halos. We devise a new quantitative and model-independent method that characterizes the existence and properties of halos in medium- to heavy-mass nuclei, and quantifies the impact of pairing correlations and the choice of the energy functional on the formation of such systems. These results are found to be limited by the predictive power of currently-used EDFs that rely on fitting to known experimental data. In the second part of this dissertation, we initiate the construction of non-empirical EDFs that make use of the new paradigm for vacuum nucleon-nucleon interactions set by so-called low-momentum interactions generated through the application of renormalization group techniques. These soft-core vacuum potentials are used as a step-stone of a long-term strategy which connects modern many-body techniques and EDF methods. We provide guidelines for designing several non-empirical models that include in-medium many-body effects at various levels of approximation, and can be handled in state-of-the art nuclear structure codes. In the present work, the first step is initiated through the adjustment of an operator representation of low-momentum vacuum interactions using a custom-designed parallel evolutionary algorithm. The first results highlight the possibility to grasp most of the relevant physics for low-energy nuclear structure using this numerically convenient Gaussian vertex. (author)

  3. Broyden's method in nuclear structure calculations

    International Nuclear Information System (INIS)

    Baran, Andrzej; Bulgac, Aurel; Forbes, Michael McNeil; Hagen, Gaute; Nazarewicz, Witold; Schunck, Nicolas; Stoitsov, Mario V.

    2008-01-01

    Broyden's method, widely used in quantum chemistry electronic-structure calculations for the numerical solution of nonlinear equations in many variables, is applied in the context of the nuclear many-body problem. Examples include the unitary gas problem, the nuclear density functional theory with Skyrme functionals, and the nuclear coupled-cluster theory. The stability of the method, its ease of use, and its rapid convergence rates make Broyden's method a tool of choice for large-scale nuclear structure calculations

  4. Future energy, exotic energy

    Energy Technology Data Exchange (ETDEWEB)

    Dumon, R

    1974-01-01

    The Detroit Energy Conference has highlighted the declining oil reserves, estimated worldwide at 95 billion tons vs. an annual rate of consumption of over 3 billion tons. The present problem is one of price; also, petroleum seems too valuable to be simply burned. New sources must come into action before 1985. The most abundant is coal, with 600 billion tons of easily recoverable reserves; then comes oil shale with a potential of 400 billion tons of oil. Exploitation at the rate of 55 go 140 million tons/yr is planned in the U.S. after 1985. More exotic and impossible to estimate quantitatively are such sources as wind, tides, and the thermal energy of the oceans--these are probably far in the future. The same is true of solar and geothermal energy in large amounts. The only other realistic energy source is nuclear energy: the European Economic Community looks forward to covering 60% of its energy needs from nuclear energy in the year 2000. Even today, from 400 mw upward, a nuclear generating plant is more economical than a fossil fueled one. Conservation will become the byword, and profound changes in society are to be expected.

  5. Nuclear Structure Studies at the Future FAIR facility

    International Nuclear Information System (INIS)

    Rubio, Berta

    2010-01-01

    This article is intended to be an introduction to studies of nuclear structure at the future FAIR facility. It addresses interested readers not necessarily expert in the field. It outlines the physics aims and experiments to be carried out at FAIR in the field of nuclear structure and astrophysics. Starting with a brief description of what can be achieved in experiments with intense, high quality stable beams the article leads the reader to how beams of unstable radioactive nuclei will be produced and exploited at FAIR. The characteristics of the beams from the main separation device, the Super-FRS, are outlined and the limitations they impose on experiment are discussed. The various setups at the three experimental branches associated with the Super-FRS are described. The aims of the various experimental setups, how they complement each other and the physics they will address are all explained. The concept of the r-process of nucleosynthesis is outlined at the beginning and used as a running example of how useful it will be to be able to carry out experiments with beams of short-lived, exotic ions.

  6. Nuclear structure of 54Cr

    International Nuclear Information System (INIS)

    Saini, S.; Gunye, M.R.

    1980-01-01

    The large amount of the experimental data accumulated in recent years on the levels of fp-shell nuclei, especially on the properties of the high spin states studied through heavy-ion reactions, needs to be explained systematically on theoretical basis. The exact shell model calculations are not feasible for most of these nuclei. The restricted shell-model calculations, however, do not give a proper account of the experimental data. The nuclear structure of 54 Cr has been investigated in the framework of Hartree-Fock Projection formation employing effective interaction in the configuration space of the full fp-shell. The band-mixed wave functions obtained from the lowest four intrinsic states have been used to compute energy levels and electromagnetic properties. The present calculations give a fairly good account of the available data. (author)

  7. Nuclear structure of 194Pt

    International Nuclear Information System (INIS)

    Cleveland, W.E.; Zganjar, E.F.

    1976-01-01

    The decay of 194 Ir has been thoroughly studied resulting in the construction of a decay scheme consisting of 26 excited states and 69 transitions. Nine new levels and 29 new transitions were added to the previously known scheme. Of these, levels at 1,893.6 and 2,053.0 keV as well as 9 γ-ray transitions are new to the 194 Pt level scheme. Precise γ-ray energy and intensity measurements as well as quantitative coincidence measurements were performed, and the internal conversion spectrum was investigated with a Si(Li) detector. Directional correlation measurements were performed for selected cascades with the major result being the unique assignment of 0 + to the new level at 1,893.6 keV. The structure was interpreted within the framework of the PPQ model as well as the effective-core picture including nuclear triaxiality. (orig.) [de

  8. Large scale nuclear structure studies

    International Nuclear Information System (INIS)

    Faessler, A.

    1985-01-01

    Results of large scale nuclear structure studies are reported. The starting point is the Hartree-Fock-Bogoliubov solution with angular momentum and proton and neutron number projection after variation. This model for number and spin projected two-quasiparticle excitations with realistic forces yields in sd-shell nuclei similar good results as the 'exact' shell-model calculations. Here the authors present results for a pf-shell nucleus 46 Ti and results for the A=130 mass region where they studied 58 different nuclei with the same single-particle energies and the same effective force derived from a meson exchange potential. They carried out a Hartree-Fock-Bogoliubov variation after mean field projection in realistic model spaces. In this way, they determine for each yrast state the optimal mean Hartree-Fock-Bogoliubov field. They apply this method to 130 Ce and 128 Ba using the same effective nucleon-nucleon interaction. (Auth.)

  9. Nuclear Structure in China 2010

    Science.gov (United States)

    Bai, Hong-Bo; Meng, Jie; Zhao, En-Guang; Zhou, Shan-Gui

    2011-08-01

    Personal view on nuclear physics research / Jie Meng -- High-spin level structures in [symbol]Zr / X. P. Cao ... [et al.] -- Constraining the symmetry energy from the neutron skin thickness of tin isotopes / Lie-Wen Chen ... [et al.] -- Wobbling rotation in atomic nuclei / Y. S. Chen and Zao-Chun Gao -- The mixing of scalar mesons and the possible nonstrange dibaryons / L. R. Dai ... [et al.] -- Net baryon productions and gluon saturation in the SPS, RHIC and LHC energy regions / Sheng-Qin Feng -- Production of heavy isotopes with collisions between two actinide nuclides / Z. Q. Feng ... [et al.] -- The projected configuration interaction method / Zao-Chun Gao and Yong-Shou Chen -- Applications of Nilsson mean-field plus extended pairing model to rare-earth nuclei / Xin Guan ... [et al.] -- Complex scaling method and the resonant states / Jian-You Guo ... [et al.] -- Probing the equation of state by deep sub-barrier fusion reactions / Hong-Jun Hao and Jun-Long Tian -- Doublet structure study in A[symbol]105 mass region / C. Y. He ... [et al.] -- Rotational bands in transfermium nuclei / X. T. He -- Shape coexistence and shape evolution [symbol]Yb / H. Hua ... [et al.] -- Multistep shell model method in the complex energy plane / R. J. Liotta -- The evolution of protoneutron stars with kaon condensate / Ang Li -- High spin structures in the [symbol]Lu nucleus / Li Cong-Bo ... [et al.] -- Nuclear stopping and equation of state / QingFeng Li and Ying Yuan -- Covariant description of the low-lying states in neutron-deficient Kr isotopes / Z. X. Li ... [et al.] -- Isospin corrections for superallowed [symbol] transitions / HaoZhao Liang ... [et al.] -- The positive-parity band structures in [symbol]Ag / C. Liu ... [et al.] -- New band structures in odd-odd [symbol]I and [symbol]I / Liu GongYe ... [et al.] -- The sd-pair shell model and interacting boson model / Yan-An Luo ... [et al.] -- Cross-section distributions of fragments in the calcium isotopes projectile

  10. Nuclear Structure Data for the Present Age

    International Nuclear Information System (INIS)

    Baglin, Coral M.

    2005-01-01

    The US Nuclear Data Program maintains and provides easy and free access to several comprehensive databases that assist scientists to sift through and assess the vast quantity of published nuclear structure and decay data. These databases are an invaluable asset for nuclear-science experimentalists and theorists alike, and the recommended values provided for nuclear properties such as decay modes, level energies and lifetimes, and radiation properties can also be of great importance to specialists in other fields such as medicine, geophysics, and reactor design. The Evaluated Nuclear Structure Data File (ENSDF) contains experimental nuclear structure data for all known nuclides, evaluated by the US nuclear data program evaluators in collaboration with a number of international data groups; the Nuclear Science Reference (NSR) database provides complementary bibliographic information; the Experimental Unevaluated Nuclear Data Listing (XUNDL) exists to enable rapid access to experimental nuclear-structure data compiled from the most recent publications (primarily in high-spin physics). This paper presents an overview of the nuclear structure and decay data available through these databases, with emphasis on recent and forthcoming additions to and presentations of the available material

  11. Antiprotonic Radioactive Atom for Nuclear Structure Studies

    International Nuclear Information System (INIS)

    Wada, M.; Yamazaki, Y.

    2005-01-01

    A future experiment to synthesize antiprotonic radioactive nuclear ions is proposed for nuclear structure studies. Antiprotonic radioactive nuclear atom can be synthesized in a nested Penning trap where a cloud of antiprotons is prestored and slow radioactive nuclear ions are bunch-injected into the trap. By observing of the ratio of π+ and π- produced in the annihilation process, we can deduce the different abundance of protons and neutrons at the surface of the nuclei. The proposed method would provide a unique probe for investigating the nuclear structure of unstable nuclei

  12. Changes in carbon pool and stand structure of a native subtropical mangrove forest after inter-planting with exotic species Sonneratia apetala.

    Science.gov (United States)

    Lu, Weizhi; Yang, Shengchang; Chen, Luzhen; Wang, Wenqing; Du, Xiaona; Wang, Canmou; Ma, Yan; Lin, Guangxuan; Lin, Guanghui

    2014-01-01

    In this study, we compared stand structure, biomass and soil carbon pools, and litterfall production between a mixed mangrove forest consisting of Aegiceras corniculatum inter-planted with the exotic Sonneratia apetala and a native monospecific forest dominated by A. corniculatum in the intertidal area of Zhanjiang, Guangdong Province, southeast China. The goal of this study was to test the hypothesis that inter-planting fast growing exotic mangrove S. apetala into subtropical native mangrove forests will significantly increase C sequestration. Although the tree heights and basal diameters of S. apetala were significantly higher than those of A. corniculatum, the density of the 12-year-old S. apetala trees in the mixed forest was much smaller than that of A. corniculatum in the monospecific forest. In contrast to several previous studies on S. apetala forests planted directly on mangrove-free mudflats, the mixed mangrove forest showed no significant difference in either standing biomass or soil carbon pools from the native monospecific mangrove forest (p = 0.294 and 0.073, respectively) twelve years after inter-planting with S. apetala. Moreover, carbon cycling was likely speeded up after inter-planting S. apetala due to higher litterfall input and lower C/N ratio. Thus, inter-planting fast-growing S. apetala into native mangrove forest is not an effective way to increase carbon sequestration in this subtropical mangrove forest. Given that exotic plant species may exert negative impact on native mangrove species and related epifauna, this fast-growing mangrove species is not suitable for mangrove plantation projects aiming mainly at enhancing carbon sequestration.

  13. Theoretical studies in nuclear reactions and nuclear structure. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon`s mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon`s mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon`s mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  14. Theoretical studies in nuclear reactions and nuclear structure

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e{sup +}e{sup {minus}} problem and heavy ion dynamics.

  15. Theoretical studies in nuclear reactions and nuclear structure

    International Nuclear Information System (INIS)

    1992-05-01

    Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has been the finding that QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate, which characterizes spontaneous chiral symmetry breaking of the late QCD vacuum, decreases in nuclear matter and this is responsible for the decrease of the nucleon's mass. The section on the structure of hadrons contains progress reports on our research aimed at understanding the structure of the nucleon. Widely different approaches are being studied, e.g., lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. A major goal of this type of research is to develop appropriate links between nuclear physics and QCD. The section on relativistic nuclear physics represents our continuing interest in developing an appropriate relativistic framework for nuclear dynamics. A Lorentz-invariant description of the nuclear force suggests a similar decrease of the nucleon's mass in the nuclear medium as has been found from QCD sum rules. Work in progress extends previous successes in elastic scattering to inelastic scattering of protons by nuclei. The section on heavy ion dynamics and related processes reports on research into the e + e - problem and heavy ion dynamics

  16. Nuclear Structure and Decay Data (NSDD) network

    International Nuclear Information System (INIS)

    Pronyaev, V.G.

    2001-02-01

    This report provides a brief description of the Nuclear Structure and Decay Data (NSDD) Network in response to a request from the Advisory Group Meeting on ''Co-ordination of the International Network of Nuclear Structure and Decay Data Evaluators'' (IAEA, Vienna, 14-17 December 1998, report IAEA(NDS)-399 (1999)). This report supersedes the special issue of the Nuclear Data Newsletter No. 20 published in November 1994. (author)

  17. Nuclear structure effects in the exotic decay of $^{225}$Ac via $^{14}$C emission

    CERN Document Server

    Bonetti, R; Guglielmetti, A; Matheoud, R; Migliorino, C; Pasinetti, A L; Ravn, H L

    1993-01-01

    By using a $^{225}$Ac source produced at the electromagnetic separator Isolde we collected on our track-recording glass detectors 305 $^{14}$C events from the radioactive decays of $^{225}$Ac and its daughter $^{221}$Fr and obtained, for $^{225}$Ac, a branching ratio B($^{14}$C/$\\alpha$)=(6.0 $\\pm$ 1.3) x 10$^{-12}$. Our result suggests that such a decay from an odd proton nucleus is dominated by transition to the ground or to the first excited state of daughter nucleus.

  18. Nuclei with exotic constituents

    International Nuclear Information System (INIS)

    Yamazaki, Toshimitsu.

    1990-08-01

    We discuss various interesting features in the behavior of exotic constituents of nuclei such as hyperons and mesons, in particular, with emphases on the aspect of exotic halos which are formed in general by short-range repulsion and long-range attraction. Specifically, Λ and Σ hypernuclei and pionic nuclei are discussed. (author)

  19. The comparison of bosonic and fermionic descriptions of collective nuclear structure

    International Nuclear Information System (INIS)

    Baktybaev, K.

    2004-01-01

    Full text: Bosonic and fermionic descriptions for the nuclear many body system are complementary. The archetypical bosonic algebra is the original interacting boson model [1]. Without distinguishing between proton and neutron bosons, it gave rise to successful phenomenology for medium and heavy nuclei, and is built from the concept of dynamical symmetry whose genesis is a group chain. The fermionic algebra on the other hand, such as the fermion dynamical symmetry model (FDSM) [2], is necessarily more complex because it originates from the shell structure and uses protons and neutrons as building blocks. We have presented two complementary pictures of bosons and fermions to describe the normal and the exotic states. We find that the bosonic concepts of symmetry and mixed- symmetry can subtly be interpreted within the fermion picture as well. However, there is one important dichotomy. In the fermion description, the n-p quadrupole interaction is responsible for splitting these two type of states and produces strong M1 transitions. This phenomenon is in close analogy to the L-S splitting of orbital and spin spaces. The examples given in the paper show that many 2 + normal and exotic states are in fact 'partners' for n-p quadrupole coupling and there fore must split in its presence. We would like to emphasize that the proper placement of the positions of the exotic states and the prediction of their respective transitions must be another stringent constraint on the effective interactions of the Hamiltonian

  20. Nuclear accident evacuee bullying and structural violence

    International Nuclear Information System (INIS)

    Tsujiuchi, Takuya

    2018-01-01

    Nuclear accident sufferers should be now referred to as nuclear accident victims. The authors discuss why nuclear accident victims receive not only psychological bullying where no peculiar causes exist, but also corporal and physical bullying and mental suffering, based on the results of questionnaire survey conducted by the authors from January to February 2017, the 'survey on bullying problems related to evacuation from the nuclear accident.' The reasons why the nuclear power evacuation bullying has become a problem at present can be largely classified to the following three categories: (1) opinion that 'bullying' that originally existed just after the nuclear accident became surfaced recently, (2) opinion that latent problems exist as background, and (3) opinion that socially underlying issues are involved in the generation of bullying. Thus, various factors existing under nuclear power evacuation bullying were structurally clarified. In the background of children's nuclear evacuation bullying, adult nuclear power evacuation bullying exists, and there are 'lack of understanding, prejudice, and discrimination against nuclear power and Fukushima' under that. The author thought that 'structural violence' to create the disparity, discrimination, inequality, and injustice of society exists as the basis of such lack of understanding, prejudice, and discrimination, and discussed the 'structural violence' as the basis of bullying. As the upper structure of structural violence associated with nuclear accidents, there are two big phenomena: (1) setting of evacuation/return area not based on reasonable radiation dose standards and (2) fabricated safety and carefreeness myth. The Ministry of Education, Culture, Sports, Science and Technology's report on nuclear bullying could give an impression that 'nuclear power evacuation bullying' is 'not so big problem'. (A.O.)

  1. ENSDF: The evaluated nuclear structure data file

    International Nuclear Information System (INIS)

    Martin, M.J.

    1986-01-01

    The structure, organization, and contents of the Evaluated Nuclear Structure Data File, ENSDF, will be discussed. This file summarizes the state of experimental nuclear structure data for all nuclei as determined from consideration of measurements reported world wide. Special emphasis will be given to the data evaluation procedures and consistency checks utilized at the input stage and to the retrieval capabilities of the system at the output stage

  2. Exotic hadron and string junction model

    International Nuclear Information System (INIS)

    Imachi, Masahiro

    1978-01-01

    Hadron structure is investigated adopting string junction model as a realization of confinement. Besides exotic hadrons (M 4 , B 5 etc.), unconventional hadrons appear. A mass formula for these hadrons is proposed. New selection rule is introduced which requires the covalence of constituent line at hadron vertex. New duality appears due to the freedom of junction, especially in anti BB→anti BB reaction. A possible assignment of exotic and unconventional hadrons to recently observed narrow meson states is presented. (auth.)

  3. Global nuclear-structure calculations

    International Nuclear Information System (INIS)

    Moeller, P.; Nix, J.R.

    1990-01-01

    The revival of interest in nuclear ground-state octupole deformations that occurred in the 1980's was stimulated by observations in 1980 of particularly large deviations between calculated and experimental masses in the Ra region, in a global calculation of nuclear ground-state masses. By minimizing the total potential energy with respect to octupole shape degrees of freedom in addition to ε 2 and ε 4 used originally, a vastly improved agreement between calculated and experimental masses was obtained. To study the global behavior and interrelationships between other nuclear properties, we calculate nuclear ground-state masses, spins, pairing gaps and Β-decay and half-lives and compare the results to experimental qualities. The calculations are based on the macroscopic-microscopic approach, with the microscopic contributions calculated in a folded-Yukawa single-particle potential

  4. Nuclear Structure Committee annual report 1976-1977, nuclear structure grants and laboratory agreements

    International Nuclear Information System (INIS)

    1977-01-01

    The Annual Report for the period 1 August 1976 to 31 July 1977 of the Nuclear Structure Committee of the Nuclear Physics Board, under the (United Kingdom) Science Research Council, is presented. Details are given of nuclear structure grants and laboratory agreements. (U.K.)

  5. Exotic aspects of hadronic atoms-anomalous quasi-stabilities

    International Nuclear Information System (INIS)

    Yamazaki, Toshimitsu.

    1993-07-01

    Recently revealed, but hitherto unknown, new aspects of hadronic atoms, namely, anomalous quasi-stabilities of negative hadrons, are discussed. One is on long-lived antiprotonic helium atoms, characterized as 'atomic exotic halo' and the other is on deeply bound pionic atoms, characterized as 'nuclear exotic halo'. (author)

  6. Structure-soil-structure interaction of nuclear structures

    International Nuclear Information System (INIS)

    Snyder, M.D.; Shaw, D.E.; Hall, J.R. Jr.

    1975-01-01

    Structure-to-structure interaction resulting from coupling of the foundations through the soil has traditionally been neglected in the seismic analysis of nuclear power plants. This paper examines the phenomenon and available methods of analytical treatment, including finite element and lumped parameter methods. Finite element techniques have lead to the treatment of through soil coupling of structural foundations using two dimensional plane strain models owing to the difficulty of considering three dimensional finite element models. The coupling problem is treated by means of a lumped parameter model derived from elastic half-space considerations. Consequently, the method is applicable to the interaction of any number of foundations and allows the simultaneous application of tri-directional excitation. The method entails the idealization of interacting structures as lumped mass/shear beams with lumped soil springs and dampers beneath each foundation plus a coupling matrix between the interacting foundations. Utilizing classical elastic half-space methods, the individual foundation soil springs and dampers may be derived, accounting for the effects of embedment and soil layering, analogous to the methods used for single soil-structure, interaction problems. The coupling matrix is derived by generating influence coefficients based on the geometric relationship of the structures using classical half-space solutions. The influence coefficients form the coupling flexibility matrix which is inverted to yield the coupling matrix for the lumped parameter model

  7. Overview of nuclear structure with electrons

    International Nuclear Information System (INIS)

    Geesaman, D. F.

    1999-01-01

    Following a broad summary of the author's view of nuclear structure in 1974, he will discuss the key elements they have learned in the past 25 years from the research at the M.I.T. Bates Linear Accelerator center and its sister electron accelerator laboratories. Electron scattering has provided the essential measurements for most of the progress. The future is bright for nuclear structure research as their ability to realistically calculate nuclear structure observables has dramatically advanced and they are increasingly able to incorporate an understanding of quantum chromodynamics into their picture of the nucleus

  8. On exotic fireballs

    International Nuclear Information System (INIS)

    Tati, T.

    1984-01-01

    Exotic fireballs found by Brazil-Japan Collaboration of Chacaltaya Emulsion Chamber Experiment are interpreted in terms of a model of hadronic matter (of which hadrons are made) based on the theory of finite degree of freedom. It is considered in our picture that exotic fireballs reveal the part left undefined in the renormalization theory of quantum field and nonappearance of exotic fireballs (of relatively small mass, i.e. Mini-Centauro and Geminion) in CERN SPS collider experiment is possibly due to the existence of universal time realized by the cutoff of momentum degree of freedom of the field of basic particles. (Author) [pt

  9. Examining work structure in nuclear power plants

    International Nuclear Information System (INIS)

    Bauman, M.B.; Boulette, M.D.; Van Cott, H.P.

    1985-01-01

    This paper describes the assessment of the work structure of ten nuclear power plants. Work structure factors are those factors that relate to the way in which work at all levels in a plant is organized, staffed, managed, rewarded, and perceived by plant personnel. Questionnaires given to a cross-section of personnel at the plants were the primary source of data collection. Structured ''critical incident'' interviews were conducted to verify the questionnaire results. The study revealed that a variety of work structure factor problem areas do exist in nuclear power plants. The paper highlights a prioritized set of candidate research themes to be considered in EPRI's Work Structure and Performance Research Program

  10. NRSAS: Nuclear Receptor Structure Analysis Servers.

    NARCIS (Netherlands)

    Bettler, E.J.M.; Krause, R.; Horn, F.; Vriend, G.

    2003-01-01

    We present a coherent series of servers that can perform a large number of structure analyses on nuclear hormone receptors. These servers are part of the NucleaRDB project, which provides a powerful information system for nuclear hormone receptors. The computations performed by the servers include

  11. New nuclear structure data beyond 136Sn

    Directory of Open Access Journals (Sweden)

    Lozeva Radomira

    2018-01-01

    Full Text Available Exotic nuclei beyond the 132Sn double shell-closure are influenced by both the Sn superfluity and the evolving collectivity only few nucleons away. Toward even more neutron-rich nuclei, especially at intermediate mass number, the interplay between single-particle and collective particle-hole excitations competes. In some cases with the extreme addition of neutrons also other effects as the formation of neutron skin, stabilization as sub-shell gaps or orbital crossings may be expected. The knowledge of nuclear ingredients is especially interesting beyond 132Sn and little is known on how the excitation modes develop with the addition of both protons and neutrons and for example systematic prompt and decay studies can be such very sensitive probe. Recently, we have approached this region of nuclei in several experimental measurements following 238U projectile fission on 9Be and n-induced fission on 241Pu and 235U. Consistent data analysis allows to access various spins and excitation energies and provide new input to theory. Examples from these studies on several nuclei in the A~140 region were presented during the conference together with the possible interpretation of the new data. Here, we will illustrate one example on 136I using two complementary data sets.

  12. New nuclear structure data beyond 136Sn

    Science.gov (United States)

    Lozeva, Radomira

    2018-05-01

    Exotic nuclei beyond the 132Sn double shell-closure are influenced by both the Sn superfluity and the evolving collectivity only few nucleons away. Toward even more neutron-rich nuclei, especially at intermediate mass number, the interplay between single-particle and collective particle-hole excitations competes. In some cases with the extreme addition of neutrons also other effects as the formation of neutron skin, stabilization as sub-shell gaps or orbital crossings may be expected. The knowledge of nuclear ingredients is especially interesting beyond 132Sn and little is known on how the excitation modes develop with the addition of both protons and neutrons and for example systematic prompt and decay studies can be such very sensitive probe. Recently, we have approached this region of nuclei in several experimental measurements following 238U projectile fission on 9Be and n-induced fission on 241Pu and 235U. Consistent data analysis allows to access various spins and excitation energies and provide new input to theory. Examples from these studies on several nuclei in the A 140 region were presented during the conference together with the possible interpretation of the new data. Here, we will illustrate one example on 136I using two complementary data sets.

  13. Collinear Laser Spectroscopy on exotic Ca isotopes towards new magic numbers N=32 and N=34

    CERN Document Server

    AUTHOR|(CDS)2084516

    For more than a century physicists have been trying to understand the striking particularities of the atomic nucleus. Although several questions remain open for stable nuclei, our current interest for exploring the properties of exotic species has revealed new and unexpected aspects of nuclear structure. The study of nuclei at extreme conditions is not only relevant for nuclear physics, it can also provide answers to questions related to astrophysical processes such as the origin of elements in the universe and the limits of existence for nuclear matter. Besides the complexity of the nuclear many-body problem, nuclear structure properties exhibit regular patterns at the so called “magic” numbers of nucleons. The understanding of these apparently simple structures has motivated the development of some of the most elegant models of nuclear physics. Up to now, most of these models have been successfully applied to describe the properties of nuclei in specific regions of the nuclear chart. Even though some mo...

  14. Microscopic calculations of nuclear structure and nuclear correlations

    International Nuclear Information System (INIS)

    Wiringa, R.B.

    1992-01-01

    A major goal in nuclear physics is to understand how nuclear structure comes about from the underlying interactions between nucleons. This requires modelling nuclei as collections of strongly interacting particles. Using realistic nucleon-nucleon potentials, supplemented with consistent three-nucleon potentials and two-body electroweak current operators, variational Monte Carlo methods are used to calculate nuclear ground-state properties, such as the binding energy, electromagnetic form factors, and momentum distributions. Other properties such as excited states and low-energy reactions are also calculable with these methods

  15. Electromagnetic studies of nuclear structure and reactions

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, F.W.; Dawson, J.F.; Heisenberg, J.H.; Calarco, J.R.

    1990-06-01

    This report contains papers on the following topics: giant resonance studies; deep inelastic scattering studies; high resolution nuclear structure work; and relativistic RPA; and field theory in the Schroedinger Representation.

  16. Neutron spectroscopy, nuclear structure, related topics. Abstracts

    International Nuclear Information System (INIS)

    Sukhovoj, A.M.

    1996-01-01

    Neutron spectroscopy, nuclear structure and related topics are considered. P, T-breaking, neutron beta decay, neutron radiative capture and neutron polarizability are discussed. Reaction with fast neutrons, methodical aspect low-energy fission are considered too

  17. Nuclear structure and fusion at the barrier

    International Nuclear Information System (INIS)

    Reisdorf, W.

    1985-01-01

    A comparative study of measured fusion excitation functions in the vicinity of the barrier reveals nuclear structure effects, due in particular to the coupling of the fusion process to direct-reaction channels. (orig.)

  18. Electromagnetic studies of nuclear structure and reactions

    International Nuclear Information System (INIS)

    Hersman, F.W.; Dawson, J.F.; Heisenberg, J.H.; Calarco, J.R.

    1990-06-01

    This report contains papers on the following topics: giant resonance studies; deep inelastic scattering studies; high resolution nuclear structure work; and relativistic RPA; and field theory in the Schroedinger Representation

  19. Reactor Structure Materials: Nuclear Fuel

    International Nuclear Information System (INIS)

    Sannen, L.; Verwerft, M.

    2000-01-01

    Progress and achievements in 1999 in SCK-CEN's programme on applied and fundamental nuclear fuel research in 1999 are reported. Particular emphasis is on thermochemical fuel research, the modelling of fission gas release in LWR fuel as well as on integral experiments

  20. Mean-field models and exotic nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Bender, M; Buervenich, T; Maruhn, J A; Greiner, W [Inst. fuer Theoretische Physik, Univ. Frankfurt (Germany); Rutz, K [Inst. fuer Theoretische Physik, Univ. Frankfurt (Germany); [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Reinhard, P G [Inst. fuer Theoretische Physik, Univ. Erlangen (Germany)

    1998-06-01

    We discuss two widely used nuclear mean-field models, the relativistic mean-field model and the (nonrelativistic) Skyrme-Hartree-Fock model, and their capability to describe exotic nuclei. Test cases are superheavy nuclei and neutron-rich Sn isotopes. New information in this regime helps to fix hitherto loosely determined aspects of the models. (orig.)

  1. Mean-field models and exotic nuclei

    International Nuclear Information System (INIS)

    Bender, M.; Buervenich, T.; Maruhn, J.A.; Greiner, W.; Rutz, K.; Reinhard, P.G.

    1998-01-01

    We discuss two widely used nuclear mean-field models, the relativistic mean-field model and the (nonrelativistic) Skyrme-Hartree-Fock model, and their capability to describe exotic nuclei. Test cases are superheavy nuclei and neutron-rich Sn isotopes. New information in this regime helps to fix hitherto loosely determined aspects of the models. (orig.)

  2. Nuclear structure in deep-inelastic reactions

    International Nuclear Information System (INIS)

    Rehm, K.E.

    1986-01-01

    The paper concentrates on recent deep inelastic experiments conducted at Argonne National Laboratory and the nuclear structure effects evident in reactions between super heavy nuclei. Experiments indicate that these reactions evolve gradually from simple transfer processes which have been studied extensively for lighter nuclei such as 16 O, suggesting a theoretical approach connecting the one-step DWBA theory to the multistep statistical models of nuclear reactions. This transition between quasi-elastic and deep inelastic reactions is achieved by a simple random walk model. Some typical examples of nuclear structure effects are shown. 24 refs., 9 figs

  3. Collective nuclear dynamics. Proceedings

    International Nuclear Information System (INIS)

    Ivanyuk, F.A.

    1994-01-01

    The Fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects:liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities

  4. Collective nuclear dynamics. Abstracts

    International Nuclear Information System (INIS)

    Abrosimov, V.I.; Kolomietz, V.M.

    1994-01-01

    The fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects: liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities

  5. Collective nuclear dynamics. Proceedings.

    Energy Technology Data Exchange (ETDEWEB)

    Ivanyuk, F A [eds.

    1994-12-31

    The Fourth International school on nuclear physics was help on 29 Aug - 7 Sep, 1994 in Ukraine. The specialists discussed following subjects:liquid drop and the shell correction method; nuclear deformation energy and fission; nuclear structure at high spins, superdeformed states, structure of excited and exotic nuclei; nuclear fluid dynamics and large scale collective motion; order and chaos as they relate to the collective motion; quantum and interference phenomena in nuclear collisions; quasi-fission and multinucleon fragmentation effects; shell effects in non-nuclear systems; new nuclear facilities.

  6. Structural materials for innovative nuclear systems (SMINS)

    International Nuclear Information System (INIS)

    2008-01-01

    Structural materials research is a field of growing relevance in the nuclear sector, especially for the different innovative reactor systems being developed within the Generation IV International Forum (GIF), for critical and subcritical transmutation systems, and of interest to the Global Nuclear Energy Partnership (GNEP). Under the auspices of the NEA Nuclear Science Committee (NSC) the Workshop on Structural Materials for Innovative Nuclear Systems (SMINS) was organised in collaboration with the Forschungszentrum Karlsruhe in Germany. The objectives of the workshop were to exchange information on structural materials research issues and to discuss ongoing programmes, both experimental and in the field of advanced modelling. These proceedings include the papers and the poster session materials presented at the workshop, representing the international state of the art in this domain. (author)

  7. Evaluated Nuclear Structure Data File (ENSDF)

    International Nuclear Information System (INIS)

    Bhat, M.R.

    1991-01-01

    The Evaluated Nuclear Structure Data File (ENSDF), is maintained by the National Nuclear Data Center (NNDC) on behalf of the international Nuclear Structure and Decay Data (NSDD) network organized under the auspices of the International Atomic Energy Agency. ENSDF provides evaluated experimental nuclear structure and decay data for basic and applied research. The activities of the NSDD network, the publication of the evaluations, and their use in different applications are described. Since 1986, the ENSDF and related numeric and bibliographic data bases have been made available for on-line access. The current status of these data bases, and future plans to improve the on-line access to their contents are discussed. 8 refs., 4 tabs

  8. Nuclear Structure of 186Re

    Science.gov (United States)

    2016-12-24

    equipotential surfaces defining the shapes of quadrupole-deformed nuclei are shown in Figure 3, in which the e↵ects of varying and are... equipotential surfaces in deformed nuclei, with the axis of nuclear symmetry identified as the z axis. The spherical shape has = 0, while the oblate...Equation (11) are seen to represent the mass-energy contained in the volume of the nucleus, adjusted for the surface tension and the Coulomb

  9. Clustering aspects in nuclear structure functions

    International Nuclear Information System (INIS)

    Hirai, M.; Saito, K.; Watanabe, T.; Kumano, S.

    2011-01-01

    For understanding an anomalous nuclear effect experimentally observed for the beryllium-9 nucleus at the Thomas Jefferson National Accelerator Facility, clustering aspects are studied in structure functions of deep inelastic lepton-nucleus scattering by using momentum distributions calculated in antisymmetrized (or fermionic) molecular dynamics (AMD) and also in a simple shell model for comparison. According to AMD, the 9 Be nucleus consists of two α-like clusters with a surrounding neutron. The clustering produces high-momentum components in nuclear wave functions, which affects nuclear modifications of the structure functions. We investigated whether clustering features could appear in the structure function F 2 of 9 Be along with studies for other light nuclei. We found that nuclear modifications of F 2 are similar in both AMD and shell models within our simple convolution description although there are slight differences in 9 Be. It indicates that the anomalous 9 Be result should be explained by a different mechanism from the nuclear binding and Fermi motion. If nuclear-modification slopes d(F 2 A /F 2 D )/dx are shown by the maximum local densities, the 9 Be anomaly can be explained by the AMD picture, namely by the clustering structure, whereas it certainly cannot be described in the simple shell model. This fact suggests that the large nuclear modification in 9 Be should be explained by large densities in the clusters. For example, internal nucleon structure could be modified in the high-density clusters. The clustering aspect of nuclear structure functions is an unexplored topic which is interesting for future investigations.

  10. Mean field approach to nuclear structure

    International Nuclear Information System (INIS)

    Nazarewicz, W.; Tennessee Univ., Knoxville, TN

    1993-01-01

    Several examples of mean-field calculations, relevant to the recent and planned low-spin experimental works, are presented. The perspectives for future studies (mainly related to spectroscopy of exotic nuclei) are reviewd

  11. The electric monopole transition: Nuclear structure, and nuclear spectroscopy

    International Nuclear Information System (INIS)

    Zganiar, E.F.

    1992-01-01

    The electric monopole (E0) transition process provides unique information on the structure of nuclei. For example, δI=0 transitions between nuclear configurations of different shape have enhanced EO components. The authors have observed I π→Iπ (I=0) transitions in 185 Pt and 184 Pt which are pure E0. This is unprecedented. Further, they have initiated searches for the location of the superdeformed band in 192 Hg utilizing internal conversion spectroscopy and, for the first time, internal pair spectroscopy. Additionally, the lifetime of the 0 + 2 level in 188 Hg was measured with a newly developed picosecond lifetime system which utilized the 0 + 2 →0 + 1 E0 internal conversion transition as an energy gate and its associated atomic X-ray as a fast trigger. The role of the E0 internal conversion process in the study of nuclear structure and as a tool in nuclear spectroscopy are discussed

  12. Techniques of nuclear structure calculations

    International Nuclear Information System (INIS)

    Dyson, R.D.

    1967-04-01

    The quasiparticle method for identical particles interacting through pairing forces has been extended by others for use with systems of neutrons and protons. The method is to project isospin from separately considered neutron and proton quasiparticle wavefunctions. This is discussed in detail, and it seems that the projection may not be important. Therefore unprojected quasiparticle wavefunctions are tried with some success as a basis of states in which to diagonalize a realistic nuclear Hamiltonian. Brief unrelated calculations on nuclei of mass 19 and the SU(3) classification of states in the p-f shell are also presented. (author)

  13. Structural mechanics in nuclear power plant

    International Nuclear Information System (INIS)

    Han Liangbi

    1998-01-01

    The main research works in structural mechanics in reactor technology are emphatically introduced. It is completed by structural mechanics engineers at Shanghai Nuclear Research and Design Institute associated with the design and construction problems for Qinshan NPP Unit 1 and Pakistani CHASNUPP. About structural mechanics problem for the containment, the rock and soft soil two different bases are considered. For the later the interaction between soil and structure is carefully studied. About the structural mechanics problem for the equipment and pipings, the three dimensional stress and fracture analyses are studied. For the structural dynamics problem, including flow induced vibration, the response analyses under earthquake and loss coolant accident loadings are studied. For pipings, the leak before break technique has been emphatically introduced. A lot of mathematical models, the used computer codes, analytical calculations and experimental results are also introduced. This is a comprehensive description about structural mechanics problem in pressurized water reactor nuclear power plant

  14. Nuclear structure studies at Saha Institute of Nuclear Physics using ...

    Indian Academy of Sciences (India)

    In-beam gamma-ray spectroscopy, carried out at the Saha Institute of Nuclear Physics in the recent past, using heavy-ion projectiles from the pelletron accelerator centres in the country and multi-detector arrays have yielded significant data on the structure of a large number of nuclei spanning different mass regions.

  15. On elastic structural elements for nuclear reactors

    International Nuclear Information System (INIS)

    Povolo, F.

    1978-03-01

    The in-pile stress-relaxation behaviour of materials usually employed for the elastic structural elements, in nuclear reactors, is critically reviewed and the results are compared with those obtained in commercial zirconium alloys irradiated under similar conditions. Finally, it is shown that, under certain conditions, some zirconium alloys may be used as an alternative material for these structural elements. (orig.) [de

  16. Progress report on nuclear structure studies

    International Nuclear Information System (INIS)

    Walters, W.B.

    1991-01-01

    In this report, new results are reported for the decay and nuclear orientation of 114,116 I and 114 Sb as well as data for the structure of daughter nuclides 114,116 Te. New results for IBM-2 calculations for the structure of 126 Xe are also reported. 6 figs., 5 tabs

  17. Structural mechanics of nuclear plant components

    International Nuclear Information System (INIS)

    Roche, R.

    1986-10-01

    Sound structural analysis are needed for designing safe and reliable components, hence his play is very important in nuclear industry. This report is a provisional writing on the good practice in structural mechanics. Emphasis is put on non elastic analysis, damage appraisal, fatigue, fracture mechanics and also on elevated temperature behaviour [fr

  18. Nuclear structure at intermediate energies: Progress report, November 1986-August 1987

    International Nuclear Information System (INIS)

    Bonner, B.E.; Mutchler, G.S.; Phillips, G.C.

    1987-01-01

    The report includes information on prior, current, and future experiments; nuclear theory; and instrumentation. Current experiments include single pion production in np scattering, spin transfer in hyperon production, photoproduction of high p/sub T/jets, and meson studies. Future experiments will continue current research and also include the production of lambda particles with heavy ions and the production of polarized antiproton beams at LEAR. Theoretical research programs are investigating the Gaussian effective potential (GEP), hadron-nucleus scattering as a function of nuclear size, nucleon structure, and exotic contributions to lambda production in pion-deuteron interactions. Instrumentation developments include proportional wire counters, other electronics, and computer systems. 13 refs., 1 tab

  19. X-ray spectroscopy from exotic atoms

    International Nuclear Information System (INIS)

    Hartmann, F.J.

    1994-01-01

    Why do experimentalists study exotic atoms, in particular antiprotonic atoms? The answer is simple: the information about electromagnetic, weak, and strong interactions that can be obtained by doing X-ray spectroscopy from exotic atoms is really worth the effort. It is possible to (1) enlarge the knowledge about the properties of exotic particles (such as mass and magnetic moment); (2) open a possibility to test quantum electrodynamics; (3) get detailed insight into the shape of nuclei (characterized by the nuclear radium and higher momenta) and even into the neutron distribution in the nucleus (neutron halo); and (4) use it as a powerful tool to learn about the strong interaction at very low relative hadron-nucleon velocities

  20. Ultra-fast timing study of exotic neutron-rich Fe isotopes

    CERN Document Server

    Olaizola, Bruno; Mach, Henryk

    The cornerstone of nuclear structure, as we know it from stable nuclei, is the existence of magic numbers. The most stable nuclei arise for completely occupied shells, closed shells, and give rise to the magic numbers. At the Valley of Stability their values are 8, 20, 28, 50, 82 and 126. The steady development of the production, separation and identication of exotic nuclei, together with the improvement of the detection techniques, makes it possible to experimentally explore nuclei further away from the Valley of Stability. These exotic nuclei with nucleon numbers supposed to be magic do not always have the properties one would expect. As extra nucleons are added (or removed) from stable nuclei, the single particle energies are modied and strong quadrupole correlations appear, which may neutralize the spherical meanfield shell gaps. The investigation of the evolution of shell structure far from stability has become a major subject in Nuclear Physics. Research in this field has strong implications also in nuc...

  1. Legacy effects overwhelm the short-term effects of exotic plant invasion and restoration on soil microbial community structure, enzyme activities, and nitrogen cycling.

    Science.gov (United States)

    Elgersma, Kenneth J; Ehrenfeld, Joan G; Yu, Shen; Vor, Torsten

    2011-11-01

    Plant invasions can have substantial consequences for the soil ecosystem, altering microbial community structure and nutrient cycling. However, relatively little is known about what drives these changes, making it difficult to predict the effects of future invasions. In addition, because most studies compare soils from uninvaded areas to long-established dense invasions, little is known about the temporal dependence of invasion impacts. We experimentally manipulated forest understory vegetation in replicated sites dominated either by exotic Japanese barberry (Berberis thunbergii), native Viburnums, or native Vacciniums, so that each vegetation type was present in each site-type. We compared the short-term effect of vegetation changes to the lingering legacy effects of the previous vegetation type by measuring soil microbial community structure (phospholipid fatty acids) and function (extracellular enzymes and nitrogen mineralization). We also replaced the aboveground litter in half of each plot with an inert substitute to determine if changes in the soil microbial community were driven by aboveground or belowground plant inputs. We found that after 2 years, the microbial community structure and function was largely determined by the legacy effect of the previous vegetation type, and was not affected by the current vegetation. Aboveground litter removal had only weak effects, suggesting that changes in the soil microbial community and nutrient cycling were driven largely by belowground processes. These results suggest that changes in the soil following either invasion or restoration do not occur quickly, but rather exhibit long-lasting legacy effects from previous belowground plant inputs.

  2. Nuclear Structure Research at Richmond

    International Nuclear Information System (INIS)

    Beausang, Cornelius W.

    2015-01-01

    The goals for the final year were; (1) to continue ongoing efforts to develop and enhance GRETINA and work towards GRETA; (2) to investigate the structure of non-yrast states in shape transitional Sm and Gd nuclei; (3) to investigate the structure of selected light Cd nuclei; (4) to exploit the surrogate reaction technique to extract (n,f) cross sections for actinide nuclei, particularly the first measurement of the 236 Pu and 237 Pu(n,f) cross sections.

  3. Theoretical nuclear structure. Progress report for 1997

    International Nuclear Information System (INIS)

    Nazarewicz, W.; Strayer, M.R.

    1997-01-01

    This research effort is directed toward theoretical support and guidance for the fields of radioactive ion beam physics, gamma-ray spectroscopy, and the interface between nuclear structure and nuclear astrophysics. The authors report substantial progress in all these areas. One measure of progress is publications and invited material. The research described here has led to more than 25 papers that are published, accepted, or submitted to refereed journals, and to 25 invited presentations at conferences and workshops

  4. Nuclear structure at intermediate energies

    International Nuclear Information System (INIS)

    Bonner, B.E.; Mutchler, G.S.

    1991-01-01

    The theme that unites the sometimes seemingly disparate experiments undertaken by the Bonner Lab Medium Energy Group is a determination to understand in detail the many facets and manifestations of the strong interaction, that which is now referred to as nonperturbative QCD. Whether we are investigating the question of just what does carry the spin of baryons, or the extent of the validity of the SU(6) wavefunctions for the excited hyperons (as will be measured in their radiative decays in our CEBAF experiment), or questions associated with the formation of a new state of matter predicted by QCD (the subject of our BNL experiments E810, E854, as well as our approved experiment at RHIC), -- all these projects share this common goal. Our other experiments represent different approaches to the same broad undertaking. LAMPF E1097 will provide definitive answers to the question of the spin dependence of the inelastic channel of pion production in the n-p interaction. FNAL E683 may well open a new field of investigation in nuclear physics: that of just how quarks and gluons interact with nuclear matter as they transverse nuclei of different sizes. In most all of the experiments mentioned above, the Bonner Lab Group is playing major leadership roles as well as doing a big fraction of the hard work that such experiments require. We use many of the facilities that are unavailable to the intermediate energy physics community and we use our expertise to design and fabricate the detectors and instrumentation that are required to perform the measurements which we decide to do

  5. Radiation damage studies of nuclear structural materials

    International Nuclear Information System (INIS)

    Barat, P.

    2012-01-01

    Maximum utilization of fuel in nuclear reactors is one of the important aspects for operating them economically. The main hindrance to achieve this higher burnups of nuclear fuel for the nuclear reactors is the possibility of the failure of the metallic core components during their operation. Thus, the study of the cause of the possibility of failure of these metallic structural materials of nuclear reactors during full power operation due to radiation damage, suffered inside the reactor core, is an important field of studies bearing the basic to industrial scientific views.The variation of the microstructure of the metallic core components of the nuclear reactors due to radiation damage causes enormous variation in the structure and mechanical properties. A firm understanding of this variation of the mechanical properties with the variation of microstructure will serve as a guide for creating new, more radiation-tolerant materials. In our centre we have irradiated structural materials of Indian nuclear reactors by charged particles from accelerator to generate radiation damage and studied the some aspects of the variation of microstructure by X-ray diffraction studies. Results achieved in this regards, will be presented. (author)

  6. Microscopic nuclear structure with sub-nucleonic degrees of freedom

    International Nuclear Information System (INIS)

    Sauer, P.U.

    1986-01-01

    The paper reviews microscopic theories of nuclear structure. The subject is discussed under the topic headings: microscopic nuclear structure with nucleons only; microscopic nuclear structure with nucleons, isobars and mesons; and microscopic nuclear structure with nucleons, mesons and dibaryons. (U.K.)

  7. An electrostatic beam line for accelerator mass spectroscopy of exotic particles

    International Nuclear Information System (INIS)

    Elmore, D.; Kubik, P.W.; Hemmick, T.; Teng, R.; Kagan, H.; Haas, P.; Boyd, R.N.; Turner, R.; Nitz, D.; Ciampa, D.; Olsen, S.L.; Gentile, T.; Haelen, T.

    1985-01-01

    An all-electrostatic charged particle spectrometer has been constructed to perform high sensitivity searches for exotic states of matter. This spectrometer consists of an electrosatic beam line capable of mass independent charged particle transport and selection together with time-of-flight, energy loss and total energy detectors. This system has been used in conjunction with the tandem electrostatic accelerator at the Nuclear Structure Research Laboratory of the University of Rochester to search for fractionally charged or anomalously heavy particles. (orig.)

  8. Nuclear structure from radioactive decay

    International Nuclear Information System (INIS)

    Wood, J.L.

    1992-01-01

    The most important aspect of the wind-up of UNISOR-based research is completion of student theses. Analysis is proceeding on extensive studies in the neutron-deficient rare earth isotopes with N 50 open shell region and shape coexistence in the N ∼ 104, Z ≤ 82 region, respectively. The main ongoing topics are shape coexistence in nuclei and the microscopic structure of collective motion in nuclei from a phenomenological point of view. New topics this year focus on the structure of nuclei near the N = Z line. Two topics have been chosen for detailed study: shape coexistence and electric monopole transition strengths

  9. Nuclear Structure Research at Richmond

    Energy Technology Data Exchange (ETDEWEB)

    Beausang, Cornelius W. [Univ. of Richmond, VA (United States)

    2015-04-30

    The goals for the final year were; (1) to continue ongoing efforts to develop and enhance GRETINA and work towards GRETA; (2) to investigate the structure of non-yrast states in shape transitional Sm and Gd nuclei; (3) to investigate the structure of selected light Cd nuclei; (4) to exploit the surrogate reaction technique to extract (n,f) cross sections for actinide nuclei, particularly the first measurement of the 236Pu and 237Pu(n,f) cross sections.

  10. Charge parity exotic mesons

    International Nuclear Information System (INIS)

    Burden, C.J.

    1998-01-01

    Full text: Evidence for a meson with exotic quantum numbers J PC 1 -+ , the ρ(1405), has been observed at the AGS at Brookhaven and Crystal Barrel at CERN. This meson is exotic to the extent that its quantum numbers are not consistent with the generalised Pauli exclusion principle applied to the naive constituent quark model. In a fully relativistic field theoretic treatment, however, there is nothing in principle to preclude the existence of charge parity exotics. Using our earlier covariant Bethe-Salpeter model of light-quark mesons with no new parameter fitting we demonstrate the existence of a q - q-bar bound state with the quantum numbers of the ρ

  11. Nuclear structure studies of neutron-rich heavy nuclei by mass measurements of francium and radium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Rosenbusch, Marco [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, 17487 Greifswald (Germany); Collaboration: ISOLTRAP-Collaboration

    2013-07-01

    The mass is a unique property of an atomic nucleus reflecting its binding energy and thus the sum of all interactions at work. Precise measurements of nuclear masses especially of short-lived exotic nuclides provide important input for nuclear structure, nuclear astrophysics, tests of the Standard Model, and weak interaction studies. The Penning-trap mass spectrometer ISOLTRAP at the on-line isotope separator ISOLDE/CERN has been set up for precision mass measurements and continuously improved for accessing more exotic nuclides. The mass uncertainty is typically δm / m=10{sup -8} and the accessible half-life has been reduced to about 50 ms. In this contribution, the results of a measurement campaign of neutron-rich francium and radium isotopes will be presented, i.e. the masses of the isotopic chain of {sup 224-233}Fr and {sup 233,234}Ra, one of the most neutron-rich ensemble obtainable at ISOL facilities. The mass {sup 234}Ra denotes the heaviest mass ever measured with ISOLTRAP. Experimental data in the neutron-rich, heavy mass region is of great interest for studies of structural evolution far from stability, especially because the knowledge from nuclear mass models is scarce. The impact of the new data on the physics in this mass region as well as recent technical developments of ISOLTRAP are discussed.

  12. Excitations in superfluid systems: contributions of the nuclear structure; Excitations dans les systemes superfluides: contributions de la structure nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Khan, E

    2005-12-15

    The author presents successively the theoretical aspect, the experimental aspect and the applied aspect of excitations in nuclear structures. The quasi-particle random phase approximation (QRPA) tool is first described. Recent approaches on QRPA are based on the theory of the density function where the ground state and excited states are described from the same nucleon-nucleon interaction. 2 methods for measuring the collective excitations are then presented: the proton scattering that has the potentiality to investigate the evolution of magicity, the second method is in fact a new method for measuring the giant mono-polar resonance (GMP) in exotic nuclei. Nuclear reactions are considered as a compulsory step on the way from observables like cross-sections to nuclear structure. The author highlights the assets of the convolution model that can generate the optical potential from the effective nucleon-nucleon interaction and from proton and neutron densities of the nuclei involved. R-processes in nucleosynthesis and neutron stars are reviewed as applications of collective excitations in the field of nuclear astrophysics. (A.C.)

  13. Reliability assessment of nuclear structural systems

    International Nuclear Information System (INIS)

    Reich, M.; Hwang, H.

    1983-01-01

    Reliability assessment of nuclear structural systems has been receiving more emphasis over the last few years. This paper deals with the recent progress made by the Structural Analysis Division of Brookhaven National Laboratory (BNL), in the development of a probability-based reliability analysis methodology for safety evaluation of reactor containments and other seismic category I structures. An important feature of this methodology is the incorporation of finite element analysis and random vibration theory. By utilizing this method, it is possible to evaluate the safety of nuclear structures under various static and dynamic loads in terms of limit state probability. Progress in other related areas, such as the establishment of probabilistic characteristics for various loads and structural resistance, are also described. Results of an application of the methodology to a realistic reinforced concrete containment subjected to dead and live loads, accidental internal pressures and earthquake ground accelerations are presented

  14. Quantum algebras in nuclear structure

    International Nuclear Information System (INIS)

    Bonatsos, D.; Daskaloyannis, C.

    1995-01-01

    Quantum algebras is a mathematical tool which provides us with a class of symmetries wider than that of Lie algebras, which are contained in the former as a special case. After a self-contained introduction through the necessary mathematical tools (q-numbers, q-analysis, q-oscillators, q-algebras), the su q (2) rotator model and its extensions, the construction of deformed exactly soluble models (Interacting Boson Model, Moszkowski model), the use of deformed bosons in the description of pairing correlations, and the symmetries of the anisotropic quantum harmonic oscillator with rational ratios of frequencies, which underline the structure of superdeformed and hyperdeformed nuclei are discussed in some details. A brief description of similar applications to molecular structure and an outlook are also given. (author) 2 Tabs., 324 Refs

  15. Introducion to Nuclear Physics course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    Atomic nuclei are made of nucleons, protons and neutrons, composed by quarks strongly interacting via gluons. How such complex objects as particles and nuclei are built? remains a fundamental question. A new "frontier" of subatomic physics is the exploration of exotic nuclei, elements and isotopes not stable enough to have survived on Earth. Exotic nuclei populated vast unknown regions of the nuclear chart where many unexpected structures have recently been discovered. Exotic nuclei synthesized in laboratory allow large variation of the neutron and proton chemical composition of nuclear systems needed to uncover the true nature of the subatomic structures and to understand the origin of elements in the Universe. This lecture will be an introduction to the open questions and key issues on the properties and structure of atomic nuclei and nuclear matter.

  16. QCD Structure of Nuclear Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Granados, Carlos [Florida Intl Univ., Miami, FL (United States)

    2011-05-25

    This dissertation investigated selected processes involving baryons and nuclei in hard scattering reactions. Through these processes, this work explored the constituent structure of baryons and the mechanisms through which the interactions between these constituents ultimately control the selected reactions. First, hard nucleon-nucleon elastic scattering was studied considering the quark exchange (QE) between the nucleons to be the dominant mechanism of interaction in the constituent picture. It was found that an angular asymmetry exhibited by proton-neutron (pn) elastic scattering data is explained within this framework if a quark-diquark picture dominates the nucleon's structure instead of a more traditional SU(6) model. The latter yields an asymmetry around 90 deg center of mass scattering with a sign opposite to what is experimentally observed. The second process is the hard breakup by a photon of a nucleon-nucleon system in light nuclei. Proton-proton (pp) and pn breakup in 3He, and double Δ-isobars production in deuteron breakup were analyzed in the hard rescattering model (HRM), which in conjunction with the QE mechanism provides a QCD description of the reaction. Cross sections for both channels in 3He photodisintegration were computed without the need of a fitting parameter. The results presented here for pp breakup show excellent agreement with recent experimental data. In double Δ-isobars production in deuteron breakup, HRM angular distributions for the two double Δ channels were compared to the pn channel and to each other. An important prediction from this study is that the Δ++ Δ- channel consistently dominates Δ+Δ0, which is in contrast with models that unlike the HRM consider a double Δ system in the initial state of the interaction. For such models both channels should have the same strength.

  17. Exotic invasive plants

    Science.gov (United States)

    Carolyn Hull Sieg; Barbara G. Phillips; Laura P. Moser

    2003-01-01

    Ecosystems worldwide are threatened by nonnative plant invasions that can cause undesirable, irreversible changes. They can displace native plants and animals, out-cross with native flora, alter nutrient cycling and other ecosystem functions, and even change an ecosystem's flammability (Walker and Smith 1997). After habitat loss, the spread of exotic species is...

  18. Exotic biological control agents

    NARCIS (Netherlands)

    Hajek, Ann E.; Hurley, Brett P.; Kenis, Marc; Garnas, Jeffrey R.; Bush, Samantha J.; Wingfield, Michael J.; Lenteren, van Joop C.; Cock, Matthew J.W.

    2016-01-01

    Biological control is a valuable and effective strategy for controlling arthropod pests and has been used extensively against invasive arthropods. As one approach for control of invasives, exotic natural enemies from the native range of a pest are introduced to areas where control is needed.

  19. Glueballs, Hybrids and Exotics

    Science.gov (United States)

    Reyes, M. A.; Moreno, G.

    2006-09-01

    We comment on the physics analysis carried out by the Experimental High Energy Physics (EHEP) group of the Instituto de Fisica of the University of Guanajuato (IFUG), Mexico. In particular, this group has been involved in analysis carried out to search for glueball, hybrid and exotic candidates.

  20. Glueballs, Hybrids and Exotics

    International Nuclear Information System (INIS)

    Reyes, M. A.; Moreno, G.

    2006-01-01

    We comment on the physics analysis carried out by the Experimental High Energy Physics (EHEP) group of the Instituto de Fisica of the University of Guanajuato (IFUG), Mexico. In particular, this group has been involved in analysis carried out to search for glueball, hybrid and exotic candidates

  1. Exotic baryonium exchanges

    International Nuclear Information System (INIS)

    Nicolescu, B.

    1978-05-01

    The prominent effects supposed to be associated with the exchange of exotic baryonium Regge trajectories are reviewed. The experimental presence of all expected effects leads to suggest that the baryonium exchange mechanism is a correct phenomenological picture and that mesons with isospin 2 or 3/2 or with strangeness 2, strongly coupled to the baryon-antibaryon channels, must be observed

  2. Exotic reptile bites.

    Science.gov (United States)

    Kelsey, J; Ehrlich, M; Henderson, S O

    1997-09-01

    Reptiles are a growing part of the exotic pet trade, and reptile bites have been considered innocuous in the emergency medicine literature. Two cases are reported of reptile bites, one from a green iguana and the other from a reticulated python. The treatment concerns associated with reptile bites are discussed.

  3. Shield structure for a nuclear reactor

    International Nuclear Information System (INIS)

    Rouse, C.A.; Simnad, M.T.

    1979-01-01

    An improved nuclear reactor shield structure is described for use where there are significant amounts of fast neutron flux above an energy level of approximately 70 keV. The shield includes structural supports and neutron moderator and absorber systems. A portion at least of the neutron moderator material is magnesium oxide either alone or in combination with other moderator materials such as graphite and iron. (U.K.)

  4. ENSL and CDRL: evaluated nuclear structure libraries

    International Nuclear Information System (INIS)

    Howerton, R.J.

    1981-01-01

    Two files of nuclear structure data derived largely from the seventh edition of the Table of Isotopes are described. The files are computer oriented, and have been constructed so that every decay can be traced either to an eventual ground state or to a positive flag that indicates nothing is known about further decay. 1 table

  5. Nuclear structure and the single charge exchange

    International Nuclear Information System (INIS)

    Oset, E.; Strottman, D.

    1979-01-01

    The influence of nuclear structure on meson-induced single-charge-exchange reactions on light nuclei is discussed within the context of the Glauber approximation. Selection rules which are expected to be approximately obeyed in elastic and inelastic pion and kaon scattering are proposed. Theoretical predictions are presented for (π + ,π 0 ) and (K + ,K 0 ) reactions on 13 C. 14 figures

  6. Nuclear structure at high excitation energies

    Indian Academy of Sciences (India)

    Average nuclear shape; giant dipole resonance; static path approximation; linear re- ... On the other hand if the nucleus is already spherical in the ground state ... this approach to study the structural properties as well as level densities of some ... (1) is modeled by a harmonic vibration along the three principal axes and then.

  7. Pion double charge exchange and nuclear structure

    International Nuclear Information System (INIS)

    Ginocchio, J.N.

    1987-01-01

    Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs

  8. Progress on nuclear modifications of structure functions

    Directory of Open Access Journals (Sweden)

    Kumano S.

    2016-01-01

    Full Text Available We report progress on nuclear structure functions, especially on their nuclear modifications and a new tensor structure function for the deuteron. To understand nuclear structure functions is an important step toward describing nuclei and QCD matters from low to high densities and from low to high energies in terms of fundamental quark and gluon degrees of freedom beyond conventional hadron and nuclear physics. It is also practically important for understanding new phenomena in high-energy heavy-ion collisions at RHIC and LHC. Furthermore, since systematic errors of current neutrinooscillation experiments are dominated by uncertainties of neutrino-nucleus interactions, such studies are valuable for finding new physics beyond current framework. Next, a new tensor-polarized structure function b1 is discussed for the deuteron. There was a measurement by HERMES; however, its data are inconsistent with the conventional convolution estimate based on the standard deuteron model with D-state admixture. This fact suggests that a new hadronic phenomenon should exist in the tensor-polarized deuteron at high energies, and it will be experimentally investigated at JLab from the end of 2010’s.

  9. High performance structural ceramics for nuclear industry

    International Nuclear Information System (INIS)

    Pujari, Vimal K.; Faker, Paul

    2006-01-01

    A family of Saint-Gobain structural ceramic materials and products produced by its High performance Refractory Division is described. Over the last fifty years or so, Saint-Gobain has been a leader in developing non oxide ceramic based novel materials, processes and products for application in Nuclear, Chemical, Automotive, Defense and Mining industries

  10. Computational nuclear structure: Challenges, rewards, and prospects

    International Nuclear Information System (INIS)

    Dean, D.J.

    1997-12-01

    The shell model Monte Carlo technique (SMMC) transforms the traditional nuclear shell model problem into a path-integral over auxiliary fields. Applications of the method to studies of various properties of fp-shell nuclei, including Gamow-Teller strengths and distributions, are reviewed. Part of the future of nuclear structure physics lies in the study of nuclei far from beta-stability. The author discusses preliminary work on proton deficient Xe isotopes, and on neutron rich nuclei in the sd-Jp shells

  11. Exotics. Heavy pentaquarks and tetraquarks

    International Nuclear Information System (INIS)

    Ali, Ahmed; Lange, Jens Soeren; Stone, Sheldon

    2017-07-01

    For many decades after the invention of the quark model in 1964 there was no evidence that hadrons are formed from anything other than the simplest pairings of quarks and antiquarks, mesons being formed of a quark-antiquark pair and baryons from three quarks. In the last decade, however, in an explosion of data from both e"+e"- and hadron colliders, there are many recently observed states that do not fit into this picture. These new particles are called generically ''exotics''. They can be either mesons or baryons. Remarkably, they all decay into at least one meson formed of either a c anti c or b anti b pair. In this review, after the introduction, we explore each of these new discoveries in detail first from an experimental point of view, then subsequently give a theoretical discussion. These exotics can be explained if the new mesons contain two-quarks and two antiquarks (tetraquarks), while the baryons contain four-quarks plus an antiquark (pentaquarks). The theoretical explanations for these states take three divergent tracks: tightly bound objects, just as in the case of normal hadrons, but with more constituents, or loosely bound ''molecules'' similar to the deuteron, but formed from two mesons, or a meson or baryon, or more wistfully, they are not multiquark states but appear due to kinematic effects caused by different rescatterings of virtual particles; most of these models have all been post-dictions. Both the tightly and loosely bound models predict the masses and related quantum numbers of new, as yet undiscovered states. Thus, future experimental discoveries are needed along with theoretical advances to elucidate the structure of these new exotic states.

  12. Exotics. Heavy pentaquarks and tetraquarks

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Lange, Jens Soeren [Giessen Univ. (Germany). II. Physikalisches Inst.; Stone, Sheldon [Syracuse Univ., Syracuse, NY (United States). Physics Dept.

    2017-07-15

    For many decades after the invention of the quark model in 1964 there was no evidence that hadrons are formed from anything other than the simplest pairings of quarks and antiquarks, mesons being formed of a quark-antiquark pair and baryons from three quarks. In the last decade, however, in an explosion of data from both e{sup +}e{sup -} and hadron colliders, there are many recently observed states that do not fit into this picture. These new particles are called generically ''exotics''. They can be either mesons or baryons. Remarkably, they all decay into at least one meson formed of either a c anti c or b anti b pair. In this review, after the introduction, we explore each of these new discoveries in detail first from an experimental point of view, then subsequently give a theoretical discussion. These exotics can be explained if the new mesons contain two-quarks and two antiquarks (tetraquarks), while the baryons contain four-quarks plus an antiquark (pentaquarks). The theoretical explanations for these states take three divergent tracks: tightly bound objects, just as in the case of normal hadrons, but with more constituents, or loosely bound ''molecules'' similar to the deuteron, but formed from two mesons, or a meson or baryon, or more wistfully, they are not multiquark states but appear due to kinematic effects caused by different rescatterings of virtual particles; most of these models have all been post-dictions. Both the tightly and loosely bound models predict the masses and related quantum numbers of new, as yet undiscovered states. Thus, future experimental discoveries are needed along with theoretical advances to elucidate the structure of these new exotic states.

  13. Superheavy Element Synthesis and Nuclear Structure

    International Nuclear Information System (INIS)

    Ackermann, D.

    2009-01-01

    The search for the next closed proton and neutron shells beyond 2 08P b has yielded a number of exciting results in terms of the synthesis of new elements [1,2,3]. The superheavy elements (SHE), however, are a nuclear structure phenomenon. They owe their existence to the quantum mechanical origin of shell correction energies without which they would not be bound. In recent years the development of efficient experimental set-ups including separators and advanced particle and photon detection arrangements allowed for more and more detailed nuclear structure studies for nuclei at and beyond Z=100. A review of those recent achievements is given in ref. [4]. Among the most interesting features is the observation of K-isomeric states. Experimentally about 14 cases have been identified in the region of Z>96 as shown in Fig. 1. K-isomers or indications of their existence have been found for almost all even-Z elements in the region Z=100 to 110. We could recently establish and/or confirm such states in the even-even isotopes 2 52,254N o [5]. The heaviest nucleus where such a state was found is 2 70D s with Z=110 as we reported in 2001 [6]. Those nuclear structure studies lay out the grounds for a detailed understanding of these heavy and high-Z nuclear systems, and contribute at the same time valuable information to preparation of strategies to successfully continue the hunt for the localisation of the next spherical proton and neutron shells after 2 08P b. The recent activities for both SHE synthesis and nuclear structure investigations at GSI will be reported.(author)

  14. Hirschegg '03: Nuclear structure and dynamics at the limits. Proceedings

    International Nuclear Information System (INIS)

    Feldmeier, H.; Knoll, J.; Noerenberg, W.; Wambach, J.

    2003-01-01

    The following topics were dealt with: Nuclear structure ans symmetries, nuclei near the drip line, halo nuclei and nuclear resonances, superheavy elements and fission, fragmentation and multifragmentation, nuclear astrophysics. (HSI)

  15. Status of exotic states at ATLAS

    CERN Document Server

    Yeletskikh, Ivan; The ATLAS collaboration

    2017-01-01

    We review the status of searches and measurements of exotic hadron states at ATLAS. Among them: the search for the beauty partner of X(3872) charmonium state, the measurement of differential cross-section of the prompt and non-prompt production of X(3872) in the J/psi pi pi final states, the search for the structure in the B_s pi invariant mass, reported by D0 experiment, search for exotic states in B-hadron decays: pentaquarks in Lambda_b decays and tetraquarks in B-meson decays. ATLAS results and ongoing analyses perspectives are highlighted together with CMS and LHCb results.

  16. Submicro and Nano Structured Porous Materials for the Production of High-Intensity Exotic Radioactive Ion Beams

    CERN Document Server

    Fernandes, Sandrina; Stora, Thierry

    2010-01-01

    ISOLDE, the CERN Isotope Separator On-line DEvice is a unique source of low energy beams of radioactive isotopes - atomic nuclei that have too many or too few neutrons to be stable. The facility is like a small ‘chemical factory’, giving the possibility of changing one element to another, by selecting the atomic mass of the required isotope beam in the mass separator, rather as the ‘alchemists’ once imagined. It produces a total of more than 1000 different isotopes from helium to radium, with half-lives down to milliseconds, by impinging a 1.4 GeV proton beam from the Proton Synchrotron Booster (PSB) onto special targets, yielding a wide variety of atomic fragments. Different components then extract the nuclei and separate them according to mass. The post-accelerator REX (Radioactive beam EXperiment) at ISOLDE accelerates the radioactive beams up to 3 MeV/u for many experiments. A wide international user radioactive ion beam (RIB) community investigates fundamental aspects of nuclear physics, particle...

  17. Formation of fast exotic atoms by radiative Coulomb capture

    International Nuclear Information System (INIS)

    Chatterjee, L.; Das, G.; Chakravorty, A.; Goswami, R.; Mondal, S.K.

    1993-01-01

    Interesting surprises in some exotic atom kinetics have been reported recently. These involve muonic atom transfer cross sections, nuclear pion capture and the q 1s effect in μCF. These can be explained if the exotic atom population contains a contributing fast component. Such fast atoms can be formed by radiative continuum to bound transitions of fast (keV) muons or pions. Cross sections for formation of such fast pionic and muonic atoms and their velocity distributions are reported. The possibility of these processes competing with the thermalisation channels and contributing effectively to the exotic atom population discussed. (orig.)

  18. Study of the Nuclear Structure of 39P Using Beta-Delayed Gamma Spectroscopy

    Science.gov (United States)

    Abromeit, Brittany; NSCL Experiment E14063 Team Team

    2016-03-01

    Investigation of nuclei with neutron and proton imbalance is at the forefront of nuclear physics research today. This is driven by the fact that the structure in these regimes may vary with that seen near the valley of stability. With eight neutrons more than the stable isotope of phosphorous, 39P is a neutron-rich exotic nucleus that has very limited information on it: previous studies of 39P produce only three known energy levels and gamma rays. The fragmentation of a 48Ca primary beam on a 564mg/cm2 thick Be target at the National Superconducting Cyclotron Laboratory (NSCL) was used to produce exotic 39Si. Using the NSCL Beta Counting System (BCS), consisting of a thick planner germanium double-sided strip detector (GeDSSD) and 16 High-purity germanium detectors in an array, SeGA, the beta-gamma coincidences from the decay of 39Si to 39P were analyzed. The resulting level scheme of 39P, including over 12 new gamma rays and energy states, confirmation of the previously measured half-life, and first-time logft values will be presented. This work was supported by the NSF under Grant No. 1401574.

  19. Far from the intermediate nuclear field

    International Nuclear Information System (INIS)

    Dietrich, K.; Wagner, G.J.; Gregoire, C.; Campi, X.; Silvestre-Brac, B.; Platchkov, S.; Mayer, B.; Abgrall, Y.; Bohigas, O.; Grange, P.; Signarbieux, C.

    1988-01-01

    Pairing correlations in nuclear physics; the BCS state and quasi-particles; the layer model; collision effects on nuclear dynamics; the theory of cluster formation (application to nucleus fragmentation); short range correlations (few-particle systems); deuterium electron scattering; dibaryonic resonances; traditional and exotic hadron probes of nuclear structure; spectral fluctuations and chaotic motion; corrections to the intermediate nuclear field (nonrelativistic and other effects); and heavy nuclei splitting and nuclear superfluidity are introduced [fr

  20. Microscopic Cluster Theory for Exotic Nuclei

    International Nuclear Information System (INIS)

    Tomaselli, M; Kuehl, T; Ursescu, D; Fritzsche, S

    2006-01-01

    For a better understanding of the dynamics of complex exotic nuclei it is of crucial importance to develop a practical microscopic theory easy to be applied to a wide range of masses. In this paper we propose to calculate the structure of neutron-rich nuclei within a dynamic model based on the EoM theory

  1. Building nuclear structures : challenges and achievements

    International Nuclear Information System (INIS)

    Gad, V.M.

    1981-01-01

    Reliability and safety are factors of prime importance in construction of civil engineering structures of nuclear facilities. There cannot be any compromise in the strength and life of the structure. This involves rigorous control of: (1) quality of materials and end products, (2) time taken for construction, (3) cost, and also continuing innovation. India has now accumulated more than three decades of experience in nuclear civil engineering and the civil engineering fraternity of India and particularly of the Department of Atomic Energy is now fully capable of designing and construction of all types of structures involved in the nuclear field. Illustrative examples are given. Dome of the CIRUS reactor was constructed in steel plates, but then there was a switch over to reinforced concrete for containment structures and subsequently to prestressed concrete. The aspects taken into consideration of the design to ensure absolute leak tightness are: (1) earthquake safeguards, (2) concrete surface protection, and (3) minimization of cracking in concrete due to pressure loading and shrinkage. Coordination charts are prepared for monitoring time required for various operations and time and motion studies are employed to cut down on construction time. Close control over the cost is kept through internal and external audit, executing the work departmentally or employing an outside agency as the occasion demands and proper selection of materials. Some of the innovations in materials use and construction techniques are mentioned. (K.M.)

  2. Proceedings of the conference on nuclear structure at the limits

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This report contains the papers from the Proceedings of the Conference on Nuclear Structure at the Limits. Some of the areas covered by these papers are: nuclear deformation; nuclear decay; nuclear spectroscopy; radioactive ion beams; nuclear models; high spin states; and heavy ion reactions. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  3. Compilations and evaluations of nuclear structure and decay date

    International Nuclear Information System (INIS)

    Lorenz, A.

    The material contained in this compilation is sorted according to eight subject categories: 1. General Compilations; 2. Basic Isotopic Properties; 3. Nuclear Structure Properties; 4. Nuclear Decay Processes: Half-lives, Energies and Spectra; 5. Nuclear Decay Processes: Gamma-rays; 6. Nuclear Decay Processes: Fission Products; 7. Nuclear Decay Processes: (Others); 8. Atomic Processes

  4. Proceedings of the conference on nuclear structure at the limits

    International Nuclear Information System (INIS)

    1996-01-01

    This report contains the papers from the Proceedings of the Conference on Nuclear Structure at the Limits. Some of the areas covered by these papers are: nuclear deformation; nuclear decay; nuclear spectroscopy; radioactive ion beams; nuclear models; high spin states; and heavy ion reactions. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  5. Exotic nuclei and radioactive beams; Noyaux exotiques et faisceaux radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Chomaz, P.

    1996-12-31

    The Nuclei called exotic are all the nuclei that it is necessary to recreate in laboratory to study them. Their life time is too short -in relation to earth age- for it remains enough on earth. The researchers are going to have at their s disposal at GANIL (Caen) with the S.P.I.R.A.L. project, exotic nuclei beams and will study new kinds of nuclear reactions to better understand the atom nucleus. (N.C.). 2 refs., 9 figs.

  6. Nuclear structure research. Progress report, August 1, 1993--July 31, 1994

    International Nuclear Information System (INIS)

    Brenner, D.S.

    1994-08-01

    The Clark University research program in nuclear structure is a collaborative effort involving Clark University personnel, staff members from Brookhaven National Laboratory and an active participation of scientists from the US and other nations. The TRISTAN on-line isotope separator and the capture γ-ray facility at the High Flux Beam Reactor have been the primary experimental foci of the program although experiments have been carried out at other installations such as the High Flux Reactor of the Institute Laue-Langevin in Grenoble and at the Tandem Van de Graaff Accelerator, Yale University. Recently, we have joined colleagues from Argonne National Laboratory, Vanderbilt University and the University of Maryland in experiments using the Fragment Mass Analyzer (FMA) at the ATLAS accelerator. Our program has four principal research themes which underlie the various research initiatives, three involving nuclear structure physics and one directed towards astrophysics. These themes are: (1) the critical role of the proton-neutron interaction in the evolution of nuclear structure and its relation to collectivity, (2) the study of exotic nuclei far-from-stability produced by radioactive ion beams (REBs), (3) the appearance and role of dynamical symmetries in nuclei and the characterization of transitions among these limits, and (4) the characterization and prediction of properties of nuclei far from stability of importance in stellar nucleosynthesis

  7. NEW WEB-BASED ACCESS TO NUCLEAR STRUCTURE DATASETS.

    Energy Technology Data Exchange (ETDEWEB)

    WINCHELL,D.F.

    2004-09-26

    As part of an effort to migrate the National Nuclear Data Center (NNDC) databases to a relational platform, a new web interface has been developed for the dissemination of the nuclear structure datasets stored in the Evaluated Nuclear Structure Data File and Experimental Unevaluated Nuclear Data List.

  8. Exotic Black Holes?

    OpenAIRE

    Brans, Carl H.

    1993-01-01

    Exotic smooth manifolds, ${\\bf R^2\\times_\\Theta S^2}$, are constructed and discussed as possible space-time models supporting the usual Kruskal presentation of the vacuum Schwarzschild metric locally, but {\\em not globally}. While having the same topology as the standard Kruskal model, none of these manifolds is diffeomorphic to standard Kruskal, although under certain conditions some global smooth Lorentz-signature metric can be continued from the local Kruskal form. Consequently, it can be ...

  9. Exotic composite vector boson

    International Nuclear Information System (INIS)

    Akama, K.; Hattori, T.; Yasue, M.

    1991-01-01

    An exotic composite vector boson V is introduced in two dynamical models of composite quarks, leptons, W, and Z. One is based on four-Fermi interactions, in which composite vector bosons are regarded as fermion-antifermion bound states and the other is based on the confining SU(2) L gauge model, in which they are given by scalar-antiscalar bound states. Both approaches describe the same effective interactions for the sector of composite quarks, leptons, W, Z, γ, and V

  10. Clusters and exotic processes

    International Nuclear Information System (INIS)

    Schiffer, J.P.

    1975-01-01

    An attempt is made to present some data which may be construed as indicating that perhaps clusters play a role in high energy and exotic pion or kaon interactions with complex (A much greater than 16) nuclei. Also an attempt is made to summarize some very recent experimental work on pion interactions with nuclei which may or may not in the end support a picture in which clusters play an important role. (U.S.)

  11. K-Isomers as a Probe of Nuclear Structure and Advanced Applications

    Science.gov (United States)

    Kondev, F. G.

    2005-05-01

    Nuclear K-isomers play a pivotal role in understanding the structure of deformed, axially symmetric nuclei. Examples are presented of recent studies of exotic multi-quasiparticle isomers in the A˜180 rare-earth region at the extreme of angular momentum and neutron number. A specific band-mixing scenario is invoked to explain the unusual decay path of the Kπ=57/2- isomer (T1/2=22 ns) in 175Hf, the highest spin K-isomer known in nature. The discovery of a suite of high-K isomers, above the previously known Kπ=23/2- (T1/2=160 d) state in 177Lu, using deep-inelastic and multi-nucleon transfer reactions is discussed.

  12. K-Isomers as a Probe of Nuclear Structure and Advanced Applications

    International Nuclear Information System (INIS)

    Kondev, F.G.

    2005-01-01

    Nuclear K-isomers play a pivotal role in understanding the structure of deformed, axially symmetric nuclei. Examples are presented of recent studies of exotic multi-quasiparticle isomers in the A∼180 rare-earth region at the extreme of angular momentum and neutron number. A specific band-mixing scenario is invoked to explain the unusual decay path of the Kπ=57/2- isomer (T1/2=22 ns) in 175Hf, the highest spin K-isomer known in nature. The discovery of a suite of high-K isomers, above the previously known Kπ=23/2- (T1/2=160 d) state in 177Lu, using deep-inelastic and multi-nucleon transfer reactions is discussed

  13. Theoretical studies in nuclear reaction and nuclear structure. Final report, January 1, 1975--June 30, 1976

    International Nuclear Information System (INIS)

    Banerjee, M.K.; Griffin, J.J.

    1977-07-01

    Progress in theoretical research is reported under the following readings: (1) few nuclear reactions, Eikonal approximations, and optical models; (2) pion reactions; (3) nuclear structure by reaction studies; (4) nuclear dynamics

  14. Core support structure for nuclear power plants

    International Nuclear Information System (INIS)

    Steinkamp, E.; Tautz, J.; Ries, H.

    1979-01-01

    A core support structure for nuclear power plants includes a grid of mutually crossing bridges and a support ring surrounding the grid and connected to ends of the outer bridges of the grid, the grid being formed of profile rod crosses having legs of given length, respective legs of pairs of adjacent crosses abutting one another endwise to form together a side of the smallest mesh opening of the grid, and weld means for securing the profile rod crosses to one another at the mutually abutting ends of the legs thereof; and method of producing the foregoing core support structure

  15. Proton-neutron interaction and nuclear structure

    International Nuclear Information System (INIS)

    Casten, R.F.

    1986-01-01

    The pervasive role of the proton-neutron interaction in nuclear structure is discussed. Particular emphasis is given to its influence on the onset of collectivity and deformation, on intruder states, and on the evolution of subshell structure. The N/sub p/N/sub n/ scheme is outlined and some applications of it to collective model calculations and to nuclei far off stability are described. The concept of N/sub p/N/sub n/ multiplets is introduced. 32 refs., 20 figs

  16. The case for exotic beams at the Holifield Heavy Ion Research Facility

    International Nuclear Information System (INIS)

    Garrett, J.D.

    1991-01-01

    The case is presented for modifying the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory to provide beams of proton-rich exotic isotopes, that do not occur terrestrially. A program of nuclear structure studies for light- and medium-mass, nearly self-conjugate nuclei and for heavy, proton-rich, quasibound nuclei is outlined, as are studies of hydrogen-burning reactions that occur in nucleosynthetic processes. Such a scientific program will provide a unique future for nuclear physics research at ORNL consistent with the long standing tradition of this laboratory

  17. Theoretical studies in nuclear reactions and nuclear structure: Progress report

    International Nuclear Information System (INIS)

    Griffin, J.J.

    1988-09-01

    This report discusses topics in nuclear theory. These general topics are: Quark physics, Quantum field theory, Relativistic nuclear physics, Nuclear dynamics, and Few-body problems and nonrelativistic methods

  18. 15th National Conference on Nuclear Structure in China

    CERN Document Server

    Wang, Ning; Zhou, Shan-Gui; Nuclear Structure in China 2014; NSC2014

    2016-01-01

    This volume is a collection of the contributions to the 15th National Conference on Nuclear Structure in China (NSC2014), held on October 25-28, 2014 in Guilin, China and hosted by Guangxi Normal University. It provides an important updated resource in the nuclear physics literature for researchers and graduate students studying nuclear structure and related topics. Recent progress made in the study of nuclear spectroscopy of high-spin states, nuclear mass and half-life, nuclear astrophysics, super-heavy nuclei, unstable nuclei, density functional theory, neutron star and symmetry energy, nuclear matter, and nuclear shell model are covered.

  19. PREFACE: 11th International Spring Seminar on Nuclear Physics: Shell Model and Nuclear Structure - achievements of the past two decades

    Science.gov (United States)

    2015-02-01

    shell model. Then, as usual, the program of the meeting consisted of general talks and more specialized contributions, which covered five main topics: i) From nuclear forces to nuclear structure; ii) Exploring nuclear structure toward the drip line; iii) Role of the shell model in the study of exotic nuclei; iv) Nuclear structure aspects outside the shell model; and v) Special topics. The main conclusions were drawn in two keynote talks given by Amand Faessler and Franco Iachello. The Conference had about 90 participants from some 20 countries [please see the list of participants]. This is well in line with the tradition of these meetings, as is the fact that more than 50% of the present participants attended one or more of the previous Seminars. We received 58 manuscripts out of the 73 invited papers and contributions presented at the Seminar. All of these have been peer reviewed and are collected in this volume. We would like to thank all the colleagues who have acted as referees to assess the suitability of the various articles for publication in the Journal of Physics: Conference Series. We are confident that the high quality of both invited and contributed papers contained in these Proceedings will be appreciated by the nuclear physics community. We gratefully acknowledge the members of the Advisory Committee for their valuable cooperation in preparing the scientific program as well as the financial support of the Istituto Nazionale di Fisica Nucleare, the University of Naples Federico II, and the Dipartimento di Fisica who helped make the Seminar possible. Angela Gargano Luigi Coraggio Nunzio Itaco Editors

  20. Studies in nuclear structure relevant to Astrophysics: theoretical and experimental efforts

    International Nuclear Information System (INIS)

    Saha Sarkar, Maitreyee

    2016-01-01

    Experimental and theoretical investigations in the region around doubly magic neutron rich 132 Sn nucleus have recently revealed many intriguing issues concerning some newer aspects of nuclear structure in such exotic environments. These nuclei lie on or close to the path of the astrophysical r-process flow. A glimpse of the implication of these studies on the r-process nucleosynthesis will be discussed. Presently, the Nuclear Physics group in Saha Institute of Nuclear Physics is working for installation of a high-current, low energy Accelerator as the primary component of the Facility for Research in low Energy Nuclear Astrophysics (FRENA), a national facility, at Kolkata. Planning for future experiments has been undertaken for successful utilization of this facility. Implantation technique has been found to be one of the most effective methods to produce isotopically pure targets. We have prepared a few isotopically pure targets using this technique. Being the slowest process of the CNO cycle, study of the 14 N(p, γ) 15 O(Q = 7297 keV) capture reaction is of high astrophysical interest. From an experiment utilizing one of the newly prepared 14 N implanted targets, a preliminary estimate of the lifetime of 6792 keV state in 15 O has been obtained, using Doppler shift attenuation method (DSAM). The sensitivity of the results with respect to the uncertainties in various input quantities has been tested. This endeavour will be helpful to design a better experiment to extract more precise lifetime for this important state

  1. Pile foundation of nuclear power plant structures

    International Nuclear Information System (INIS)

    Jurkiewicz, W.J.; Thomaz, E.; Rideg, P.; Girao, M.

    1978-01-01

    The subject of pile foundation used for nuclear power plant structures, considering the experience gained by the designers of the Angra Nuclear Power Plant, Units 2 and 3 in Brazil is dealt with. The general concept of the pile foundations, including types and execution of the piles, is described briefly. Then the two basic models, i.e. the static model and the dynamic one, used in the design are shown, and the pertinent design assumptions as related to the Angra project are mentioned. The criteria which established the loading capacity of the piles are discussed and the geological conditions of the Angra site are also explained briefly, justifying the reasons why pile foundations are necessary in this project. After that, the design procedures and particularly the tools - i.e. the computer programs - are described. It is noted that the relatively simple but always time consuming job of loading determination calculations can be computerized too, as it was done on this project through the computer program SEASA. The interesting aspects of soil/structure interaction, applicable to static models, are covered in detail, showing the theoretical base wich was used in the program PILMAT. Then the advantage resulting from computerizing of the job of pile reinforcement design are mentioned, describing briefly the jobs done by the two special programs PILDES and PILTAB. The point is stressed that the effort computerizing the structural design of this project was not so much due to the required accuracy of the calculations, but mainly due to the need to save on the design time, as to allow to perform the design task within the relatively tight time schedule. A conclusion can be drawn that design of pile foundations for nuclear power plant structures is a more complex task than the design of bearing type of foundation for the same structures, but that the task can be always made easier when the design process can be computerized. (Author)

  2. Abstracts of contributed papers. Sixth international conference on high-energy physics and nuclear structure, Santa Fe and Los Alamos, NM, June 9--14, 1975

    International Nuclear Information System (INIS)

    Mischke, R.; Hargrove, C.; Hoffman, C.

    1975-08-01

    Abstracts of contributed papers are assembled under the following headings (number denotes the number of abstracts in the section): pi p and pi d interactions (10); π nucleus theory (33); intermediate isobar calculations (8); π-nucleus interactions (25); stopping muons (44); exotic atoms and condensed nuclear states (28); nucleus-nucleus interactions (31); nuclear structure and hypernuclei (7); nucleon-nucleon interactions (24); e- and γ-nucleus interactions (29); weak interactions (17); high energy collisions (13); heavy ions (22); instrumentation (8). (SDF)

  3. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors

  4. Nuclear chemistry

    International Nuclear Information System (INIS)

    Vertes, A.; Kiss, I.

    1987-01-01

    This book is an introduction to the application of nuclear science in modern chemistry. The first group of chapters discuss the basic phenomena and concepts of nuclear physics with emphasis on their relation to chemical problems, including the main properties and the composition of atomic nuclei, nuclear reactions, radioactive decay and interactions of radiation with matter. These chapters provide the basis for understanding the following chapters which encompass the wide scope of nuclear chemistry. The methods of the investigation of chemical structure based on the interaction of nuclear radiation with matter including positronium chemistry and other exotic atoms is elaborated in particular detail. Separate chapters are devoted to the use of radioactive tracers, the chemical consequences of nuclear processes (i.e. hot atom chemistry), radiation chemistry, isotope effects and their applications, and the operation of nuclear reactors. (Auth.)

  5. Nuclear Structure: Dubna Symposium 1968. Invited Papers from the International Symposium on Nuclear Structure

    International Nuclear Information System (INIS)

    1968-01-01

    Invited papers of a Symposium organized by the Joint Institute for Nuclear Research, Dubna, supported by IUPAP and IAEA, and held in Dubna from 4 to 11 July 1968. The meeting was attended by about 450 scientists from 30 countries. The volume contains the invited papers, all by distinguished scientists, and the discussions and short contributions that followed the presentation of these papers. Contents: I. Nuclear structure at low excitations (15 papers) ; II. Nuclear structure at high excitations (6 papers): III. Open problems in nuclear physics (3 papers); IV. Equilibrium deformations (6 papers); V. General properties of nuclei (6 papers); VI. Closing remarks; List of contributions; List of seminar papers; List of participants; Author index. All papers, discussions and short contributions are in English; the abstracts are in English and Russian, which were the working languages of the Symposium. (author)

  6. Parquet theory in nuclear structure calculations

    International Nuclear Information System (INIS)

    Bergli, Elise

    2010-01-01

    The thesis concerns a numerical implementation of the Parquet summation of diagrams within Green's functions theory applied to calculations of nuclear systems. The main motivation has been to investigate whether it is possible to develop this approach to a level comparable in accuracy and reliability to other ab initio nuclear structure methods. The Green's functions approach is theoretically well-established in many-body theory, but to our knowledge, no actual application to nuclear systems has been previously published. It has a number of desirable properties, foremost the gently scaling with system size compared to direct diagonalization and the closeness to experimentally accessible quantities. The main drawback is the numerical instabilities due to the pole structure of the one-particle propagator, leading to convergence difficulties. This issue is one of the main focal points of the work presented in this thesis, and strategies to improve the convergence properties are described and investigated. We have applied the method both to a simple model which can be solved by exact diagonalization and to the more realistic 4 He system. The results shows that our implementation is close to the exact solution in the simple model as long as the interaction strengths are small. As the number of particles increases, convergence is increasingly hard to obtain. In the 4 He case, we obtain results in the vicinity of the results from comparable approaches. The numerical in-stabilities in the current implementation still prevents the desired accuracy and stability necessary to achieve the current benchmark standards. (Author)

  7. Light ion reaction mechanisms and nuclear structure

    International Nuclear Information System (INIS)

    Robson, B.A.

    1986-01-01

    Of the many contributions to the subject 'Light ion reaction mechanism and nuclear structure', a few are selected and reviewed which highlight the present state of the field. Some contributions to the conference dealing with nuclear interactions are briefly outlined in the second section following an introductory section. Lane model calculations are compared with data for 9 Be and results are given showing angular distributions of the cross sections, the analyzing powers and the spin-rotation parameters for p - 40 Ca. Real central potential for d + 32 s resulting from the FB-analysis are compared with frozen density folding and delta-function folding. The third section deals with reaction mechanism. Data are cited which show near-side and far-side contributions to the calculated analyzing powers in the 116 Sn(d,p) 117 Sn (11.2 - ) transition. Calculations are compared with experimental A y and -(A yy + 2)/3. Also given are measurements of the cross sections and analyzing powers of the continuum energy spectra for the 58 Ni(p,p'x), along with relations between the analyzing powers and momentum transfer. The fourth section addresses nuclear structure. Cross sections and analyzing powers measured at 22 MeV for the reaction 208 Pb(p,t) 206 Pb(3 2 + ) are cited and considered. (Nogami, K.)

  8. Inspection of Nuclear Power Plant Containment Structures

    Energy Technology Data Exchange (ETDEWEB)

    Graves, H.L.; Naus, D.J.; Norris, W.E.

    1998-12-01

    Safety-related nuclear power plant (NPP) structures are designed to withstand loadings from a number of low-probability external and interval events, such as earthquakes, tornadoes, and loss-of-coolant accidents. Loadings incurred during normal plant operation therefore generally are not significant enough to cause appreciable degradation. However, these structures are susceptible to aging by various processes depending on the operating environment and service conditions. The effects of these processes may accumulate within these structures over time to cause failure under design conditions, or lead to costly repair. In the late 1980s and early 1990s several occurrences of degradation of NPP structures were discovered at various facilities (e.g., corrosion of pressure boundary components, freeze- thaw damage of concrete, and larger than anticipated loss of prestressing force). Despite these degradation occurrences and a trend for an increasing rate of occurrence, in-service inspection of the safety-related structures continued to be performed in a somewhat cursory manner. Starting in 1991, the U.S. Nuclear Regulatory Commission (USNRC) published the first of several new requirements to help ensure that adequate in-service inspection of these structures is performed. Current regulatory in-service inspection requirements are reviewed and a summary of degradation experience presented. Nondestructive examination techniques commonly used to inspect the NPP steel and concrete structures to identify and quantify the amount of damage present are reviewed. Finally, areas where nondestructive evaluation techniques require development (i.e., inaccessible portions of the containment pressure boundary, and thick heavily reinforced concrete sections are discussed.

  9. Nuclear structure calculations for astrophysical applications

    International Nuclear Information System (INIS)

    Moeller, P.; Kratz, K.L.

    1992-01-01

    Here we present calculated results on such diverse properties as nuclear energy levels, ground-state masses and shapes, β-decay properties and fission-barrier heights. Our approach to these calculations is to use a unified theoretical framework within which the above properties can all be studied. The results are obtained in the macroscopic-microscopic approach in which a microscopic nuclear-structure single-particle model with extensions is combined with a macroscopic model, such as the liquid drop model. In this model the total potential energy of the nucleus may be calculated as a function of shape. The maxima and minima in this function correspond to such features as the ground state, fission saddle points and shape-isomeric states. Various transition rate matrix elements are determined from wave-functions calculated in the single-particle model with pairing and other relevant residual interactions taken into account

  10. Phonons as building blocks in nuclear structure

    International Nuclear Information System (INIS)

    Silvestre-Brac, B.

    1980-01-01

    The structure of a nuclear system in terms of eigenmodes (phonons) of subsystems is investigated in three different approaches. In the frame of nuclear field theory the three identical particle system is analysed and the elimination of spurious states due to the violation of the Pauli principle is emphasized. In terms of weak coupling, a new approach of the shell model is proposed which is shown to be rapidly convergent with the number of basis vectors. Applications of three particle systems in the lead region are made. Lastly, a microscopic multiphonon theorie of collective K=0 states in deformed nuclei based on a Tamm Dancoff phonon is developed. The role of the Pauli principle as well as comparisons with boson expansion methods are deeply analysed [fr

  11. ATLAS Exotic Searches

    CERN Document Server

    Bousson, Nicolas

    2012-01-01

    Thanks to the outstanding performance of the Large Hadron Collider (LHC) that delivered more than 2 fb^-1 of proton-proton collision data at center-of-mass energy of 7 TeV, the ATLAS experiment has been able to explore a wide range of exotic models trying to address the questions unanswered by the Standard Model of particle physics. Searches for leptoquarks, new heavy quarks, vector-like quarks, black holes, hidden valley and contact interactions are reviewed in these proceedings.

  12. Exotic searches at lep

    International Nuclear Information System (INIS)

    Seager, P.

    2001-01-01

    The search for exotic processes at LEP is presented. The Standard Model Higgs has as yet not been observed. This provides freedom to search for processes beyond the Standard Model and even beyond the minimal version of the supersymmetric extension to the Standard Model. This paper outlines the searches for charged Higgs bosons, fermiophobic Higgs bosons, invisibly decaying Higgs bosons, technicolor, leptoquarks, unstable heavy leptons and excited leptons. The results presented are those from the LEP collaborations using data taken up to a centre-of-mass energy of √s = 202 GeV. (author)

  13. Exotic objects of atomic physics

    Science.gov (United States)

    Eletskii, A. V.

    2017-11-01

    There has been presented a short survey of physical properties, methods of production and exploration as well as directions of practical usage of the objects of atomic physics which are not yet described in detail in modern textbooks and manuals intended for students of technical universities. The family of these objects includes negative and multicharged ions, Rydberg atoms, excimer molecules, clusters. Besides of that, in recent decades this family was supplemented with new nanocarbon structures such as fullerenes, carbon nanotubes and graphene. The textbook “Exotic objects of atomic physics” [1] edited recently contains some information on the above-listed objects of the atomic physics. This textbook can be considered as a supplement to classic courses of atomic physics teaching in technical universities.

  14. Status of transactinium nuclear data in the evaluated nuclear structure data file

    International Nuclear Information System (INIS)

    Ewbank, W.B.

    1980-01-01

    The structure and organization of the Evaluated Nuclear Structure Data File (ENSDF) which serves as the source data base for the production of drawings and tables for the ''Nuclear Data Sheets'' journal is described. The updating and output features of ENSDF are described with emphasis on nuclear structure and decay data of the transactinium isotopes. (author)

  15. Nuclear matrix - structure, function and pathogenesis.

    Science.gov (United States)

    Wasąg, Piotr; Lenartowski, Robert

    2016-12-20

    The nuclear matrix (NM), or nuclear skeleton, is the non-chromatin, ribonucleoproteinaceous framework that is resistant to high ionic strength buffers, nonionic detergents, and nucleolytic enzymes. The NM fulfills a structural role in eukaryotic cells and is responsible for maintaining the shape of the nucleus and the spatial organization of chromatin. Moreover, the NM participates in several cellular processes, such as DNA replication/repair, gene expression, RNA transport, cell signaling and differentiation, cell cycle regulation, apoptosis and carcinogenesis. Short nucleotide sequences called scaffold/matrix attachment regions (S/MAR) anchor the chromatin loops to the NM proteins (NMP). The NMP composition is dynamic and depends on the cell type and differentiation stage or metabolic activity. Alterations in the NMP composition affect anchoring of the S/MARs and thus alter gene expression. This review aims to systematize information about the skeletal structure of the nucleus, with particular emphasis on the organization of the NM and its role in selected cellular processes. We also discuss several diseases that are caused by aberrant NM structure or dysfunction of individual NM elements.

  16. Compilations and evaluations of nuclear structure and decay data

    International Nuclear Information System (INIS)

    Lorenz, A.

    1978-10-01

    This is the fourth issue of a report series on published and to-be-published compilations and evaluations of nuclear structure and decay (NSD) data. This compilation is published and distributed by the IAEA Nuclear Data Section every year. The material contained in this compilation is sorted according to eight subject categories: General compilations; basic isotopic properties; nuclear structure properties; nuclear decay processes, half-lives, energies and spectra; nuclear decay processes, gamma-rays; nuclear decay processes, fission products; nuclear decay processes (others); atomic processes

  17. [Electromagnetic studies of nuclear structure and reactions

    International Nuclear Information System (INIS)

    1991-01-01

    The past year has seen continued progress in our efforts. On the experimental side, we completed data acquisition on our major remaining involvement at NIKHEF, the 12 C(e,e'pp) experiment. We advanced the analysis of most of projects in low lying nuclear structure and giant resonances, of which several were completed and published. We received approval for several new experiments, and have made major contributions to design and development of detectors to be used at Bates and CEBAF. Our data interpretation efforts have been extended and enhanced with the availability of our new computer cluster. In this paper we briefly report on most of these efforts

  18. Structure for nuclear fuel storage pools

    International Nuclear Information System (INIS)

    Ebata, Sakae; Nichiei, Shinji.

    1979-01-01

    Purpose: To enable leak detection in nuclear fuel storage pools, as well as prevent external leakages while keeping the strength of the constructional structures. Constitution: Protection plates are provided around pool linear plates and a leak reception is provided to the bottom. Leakages are detected by leak detecting pipeways and the external leakages are prevented by collecting them in a detection area provided in the intermediate layer. Since ferro-reinforcements at the bottom wall of the pool are disconnected by the protection plate making it impossible to form the constructional body, body hunches are provided to the bottom wall of the pool for processing the ferro-reinforcements. (Yoshino, Y.)

  19. ENSL and CDRL: Evaluated nuclear structure libraries

    International Nuclear Information System (INIS)

    Howerton, R.J.

    1981-01-01

    Two files of nuclear structure data derived largely from the seventh edition of the Table of Isotopes are described. The files are computer oriented, and have been constructed to so that every decay can be traced either to an eventual ground state of to a positive flag that indicates nothing is known about further decay. The ENSL file contains level schemes derived from decay data, and the CDRL file contains the level schemes derived from particle-induced reaction data that have been merged into the ENSL file. (author)

  20. Superheavy Element Synthesis And Nuclear Structure

    International Nuclear Information System (INIS)

    Ackermann, D.; Block, M.; Burkhard, H.-G.; Heinz, S.; Hessberger, F. P.; Khuyagbaatar, J.; Kojouharov, I.; Mann, R.; Maurer, J.; Antalic, S.; Saro, S.; Venhart, M.; Hofmann, S.; Leino, M.; Uusitalo, J.; Nishio, K.; Popeko, A. G.; Yeremin, A. V.

    2009-01-01

    After the successful progress in experiments to synthesize superheavy elements (SHE) throughout the last decades, advanced nuclear structure studies in that region have become feasible in recent years thanks to improved accelerator, separation and detection technology. The means are evaporation residue(ER)-α-α and ER-α-γ coincidence techniques complemented by conversion electron (CE) studies, applied after a separator. Recent examples of interesting physics to be discovered in this region of the chart of nuclides are the studies of K-isomers observed in 252,254 No and in 270 Ds.

  1. Chiral nucleon-nucleon forces in nuclear structure calculations

    Directory of Open Access Journals (Sweden)

    Coraggio L.

    2016-01-01

    Full Text Available Realistic nuclear potentials, derived within chiral perturbation theory, are a major breakthrough in modern nuclear structure theory, since they provide a direct link between nuclear physics and its underlying theory, namely the QCD. As a matter of fact, chiral potentials are tailored on the low-energy regime of nuclear structure physics, and chiral perturbation theory provides on the same footing two-nucleon forces as well as many-body ones. This feature fits well with modern advances in ab-initio methods and realistic shell-model. Here, we will review recent nuclear structure calculations, based on realistic chiral potentials, for both finite nuclei and infinite nuclear matter.

  2. Time-space structure of nuclear safety

    International Nuclear Information System (INIS)

    Miya, Kenzo

    2003-01-01

    New idea to analyze the structure of nuclear safety and to investigate functioning property of hierarchical principle is applied to nuclear safety in this paper. The nuclear safety is expressed by three principles such as 1) the action and subject are partitioned and classified by time and space, 2) introduction of hierarchy with three strata to the closed object and hierarchy with many strata to the open object and 3) application of 'element, relation and abstraction' to the engineering system as a framework of intellectual activity. For example, prevention of core melt is the closed object and it is obtained by acting hierarchies with three strata (operation stop, cooling and closing radiation) as the safety functions. Prevention of increase of accident is open object, so that, space hierarchy with many strata of prevention is used for the safety security of reactor. The safety security method of reactor consists of three processes, that is 1) the basic process to make clear the continuous operating time on the basis of regular inspection, 2) the action process of operating ECCS to prevent core damage accident, when a large leakage happens and 3) many strata prevention process of stopping a leak in the environment. (S.Y.)

  3. Tungsten - Yttrium Based Nuclear Structural Materials

    Science.gov (United States)

    Ramana, Chintalapalle; Chessa, Jack; Martinenz, Gustavo

    2013-04-01

    The challenging problem currently facing the nuclear science community in this 21st century is design and development of novel structural materials, which will have an impact on the next-generation nuclear reactors. The materials available at present include reduced activation ferritic/martensitic steels, dispersion strengthened reduced activation ferritic steels, and vanadium- or tungsten-based alloys. These materials exhibit one or more specific problems, which are either intrinsic or caused by reactors. This work is focussed towards tungsten-yttrium (W-Y) based alloys and oxide ceramics, which can be utilized in nuclear applications. The goal is to derive a fundamental scientific understanding of W-Y-based materials. In collaboration with University of Califonia -- Davis, the project is designated to demonstrate the W-Y based alloys, ceramics and composites with enhanced physical, mechanical, thermo-chemical properties and higher radiation resistance. Efforts are focussed on understanding the microstructure, manipulating materials behavior under charged-particle and neutron irradiation, and create a knowledge database of defects, elemental diffusion/segregation, and defect trapping along grain boundaries and interfaces. Preliminary results will be discussed.

  4. Reliability of structural materials in nuclear industry

    International Nuclear Information System (INIS)

    Pinard Legry, G.

    1996-01-01

    The reliability of nuclear installations is a fundamental point for the exploitation of nuclear energy. It requires an extensive knowledge of the behaviour of materials in the operating conditions and during the expected service life of the installations. In nuclear power plants multiple risks of failure can exist and are expressed by corrosion and deformation phenomena or by modification in the mechanical characteristics of materials. The knowledge of the evolution with time of a given material requires to take into account the data relative to the material itself, to its environment and to the physical conditions of this environment. The study of materials aging needs a more precise knowledge of the kinetics of phenomena at any scale and of their interactions, and a micro- or macro-modeling of their behaviour during long periods of time. This paper gives an overview of the aging phenomena that occur in the structural materials involved in PWR and fast neutron reactors: thermal aging, generalized corrosion, corrosion under constraint, intergranular corrosion, crack growth under loading, wear, irradiation etc.. (J.S.)

  5. The 1989 annual report: Nuclear Physics Institute

    International Nuclear Information System (INIS)

    1989-01-01

    The 1988 annual report of the Nuclear Physics Institute (Orsay, France) is presented. The results concerning exotic nuclei and structure studies by means of nuclear reactions are summarized. Research works involving the inertial fusion and the actinides are discussed. Theoretical and experimental work on the following fields is also included: high excitation energy nuclear states, heavy ion collision, intermediate energy nuclear physics, transfer reactions, dibaryonic resonances, thermodiffusion, management of radioactive wastes [fr

  6. Structural considerations in nuclear life extension

    International Nuclear Information System (INIS)

    Dodson, W.B.; McHale, P.F.

    1986-01-01

    The ability to extend the licensed life of a nuclear power plant requires that technical, economic, and regulatory criteria be satisfied. Two ongoing Electric Power Research Institute/US Department of Energy funded pilot studies are looking at the technical and economic aspects from a plant wide viewpoint to life extension. In each, structures have been identified to have a potentially strong effect on the viability for extended life because of the possible major cost, schedule, and person-rem factors should major refurbishment, modifications, or replacement be required. This paper reviews the degradation mechanisms and counterbalancing design features for one of these pilot plants in the studies. It further reviews the recommended ongoing practices to be followed to better ensure that life extension for the structures remains a future option

  7. Development of analysis methods for seismically isolated nuclear structures

    International Nuclear Information System (INIS)

    Yoo, Bong; Lee, Jae-Han; Koo, Gyeng-Hoi

    2002-01-01

    KAERI's contributions to the project entitled Development of Analysis Methods for Seismically Isolated Nuclear Structures under IAEA CRP of the intercomparison of analysis methods for predicting the behaviour of seismically isolated nuclear structures during 1996-1999 in effort to develop the numerical analysis methods and to compare the analysis results with the benchmark test results of seismic isolation bearings and isolated nuclear structures provided by participating countries are briefly described. Certain progress in the analysis procedures for isolation bearings and isolated nuclear structures has been made throughout the IAEA CRPs and the analysis methods developed can be improved for future nuclear facility applications. (author)

  8. Development of structural steels for nuclear application

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jun Hwa; Chi, S. H.; Ryu, W. S.; Lee, B. S.; Kim, D. H.; Kim, J. H.; Oh, Y. J.; Byun, T. S.; Yoon, J. H.; Park, D. K.; Oh, J. M.; Cho, H. D.; Kim, H.; Kim, H. D.; Kang, S. S.; Kim, J. W.; Ahn, S. B.

    1997-08-01

    To established the bases of nuclear structural material technologies, this study was focused on the localization and improvement of nuclear structural steels, the production of material property data, and technology developments for integrity evaluation. The important test and analysis technologies for material integrity assessment were developed, and the materials properties of the pressure vessel steels were evaluated systematically on the basis of those technologies, they are microstructural characteristics, tensile and indentation deformation properties, impact properties, and static and dynamic fracture toughness, fatigue and corrosion fatigue etc. Irradiation tests in the research reactors were prepared or completed to obtain the mechanical properties of irradiated materials. The improvement of low alloy steel was also attempted through the comparative study on the manufacturing processes, computer assisted alloy and process design, and application of the inter critical heat treatment. On the other hand, type 304 stainless steels for reactor internals were developed and tested successfully. High strength type 316LN stainless steels for reactor internals were developed and the microstructural characteristics, corrosion resistance, mechanical properties at high temperatures, low cycle fatigue property etc. were tested and analyzed in the view point of the effect of nitrogen. Type 347 stainless steels with high corrosion resistance and toughness for pipings and tubes and low-activated Cr-Mn steels were also developed and their basic properties were evaluated. Finally, the martensitic stainless steels for turbine blade were developed and tests. (author). 242 refs., 100 tabs., 304 figs.

  9. Nuclear structure research. Annual progress report

    International Nuclear Information System (INIS)

    Wood, J.L.

    1994-01-01

    The most significant development this year has been the outcome of a survey of EO transition strength, ρ 2 (EO), in heavy nuclei. The systematics of ρ 2 (EO) reveals that the strongest EO's are between pairs of excited states with the same spin and parity. This is observed in the regions Z,N = 38,60; 48,66; 64,88; and 80,106. Unlike other multipoles it is rare that nuclear ground states are strongly connected to excited states by monopole transitions. Another significant finding is in the results of the experimental study of levels in 187 Au. Two bands of states are observed with identical spin sequences, very similar excitation energies, and EO transitions between the favored band members but not between the unfavored band members. This is interpreted in terms of nearly identical diabatic structures. Experimental data sets for the radioactive decays of 183 Pt and 186 Au to 183 Ir and 186 Pt, respectively, have been under analysis. The studies are aimed at elucidating shape coexistence and triaxiality in the A = 185 region. An extensive program of systematics for nuclei at and near N = Z has been continued in preparation for the planned nuclear structure research program using the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge. A considerable effort has been devoted to HRIBF target development

  10. Development of structural steels for nuclear application

    International Nuclear Information System (INIS)

    Hong, Jun Hwa; Chi, S. H.; Ryu, W. S.; Lee, B. S.; Kim, D. H.; Kim, J. H.; Oh, Y. J.; Byun, T. S.; Yoon, J. H.; Park, D. K.; Oh, J. M.; Cho, H. D.; Kim, H.; Kim, H. D.; Kang, S. S.; Kim, J. W.; Ahn, S. B.

    1997-08-01

    To established the bases of nuclear structural material technologies, this study was focused on the localization and improvement of nuclear structural steels, the production of material property data, and technology developments for integrity evaluation. The important test and analysis technologies for material integrity assessment were developed, and the materials properties of the pressure vessel steels were evaluated systematically on the basis of those technologies, they are microstructural characteristics, tensile and indentation deformation properties, impact properties, and static and dynamic fracture toughness, fatigue and corrosion fatigue etc. Irradiation tests in the research reactors were prepared or completed to obtain the mechanical properties of irradiated materials. The improvement of low alloy steel was also attempted through the comparative study on the manufacturing processes, computer assisted alloy and process design, and application of the inter critical heat treatment. On the other hand, type 304 stainless steels for reactor internals were developed and tested successfully. High strength type 316LN stainless steels for reactor internals were developed and the microstructural characteristics, corrosion resistance, mechanical properties at high temperatures, low cycle fatigue property etc. were tested and analyzed in the view point of the effect of nitrogen. Type 347 stainless steels with high corrosion resistance and toughness for pipings and tubes and low-activated Cr-Mn steels were also developed and their basic properties were evaluated. Finally, the martensitic stainless steels for turbine blade were developed and tests. (author). 242 refs., 100 tabs., 304 figs

  11. Diagnostic imaging of exotic pets

    International Nuclear Information System (INIS)

    Silverman, S.

    1993-01-01

    Radiographic, ultrasonographic, and computed tomographic (CT) imaging are important diagnostic modalities in exotic pets. The use of appropriate radiographic equipment, film-screen combinations, and radiographic projections enhances the information obtained from radiographs. Both normal findings and common radiographic abnormalities are discussed. The use of ultrasonography and CT scanning for exotic small mammals and reptiles is described

  12. Current Status of Exotic Hadrons

    International Nuclear Information System (INIS)

    Saeed, M.A.; Ahmed, Maqsood; Fazal-e-Aleem

    2005-01-01

    Physics of exotic hadrons is in the limelight these days. The models for these baryons are discussed as well as their production and decay processes and methods of their identification. The results of recent experiments in this field are presented, in which some unusual states are observed. These states are candidates for exotic hadrons

  13. LHCB : Exotic hadrons at LHCb

    CERN Multimedia

    Salazar De Paula, Leandro

    2015-01-01

    The latest years have seen a resurrection of interest in searches for exotic states motivated by tantalising observations by Belle and CDF. Using the data collected at pp collisions at 7 and 8 TeV by the LHCb experiment we present the unambiguous new observation of exotic charmonia hadrons produced in B decays.

  14. Recent Astrophysical Studies with Exotic Beams at ORNL

    Energy Technology Data Exchange (ETDEWEB)

    Bardayan, Daniel W [ORNL

    2006-02-01

    The availability of exotic beams has produced great opportunities for advances in our understanding of the nucleosynthesis occurring in stellar burning and stellar explosions such as novae, X-ray bursts, and supernovae. In these extreme environments, synthesized radioactive nuclei can undergo subsequent nuclear processing before they decay, and thus to understand these events, we must understand reaction rates involving radioactive nuclei. At the ORNL Holi led Radioactive Ion Beam Facility (HRIBF), we have made several recent measurements using proton-rich beams such as 18F and 7Be and neutron-rich beams such as 82Ge and 84Se that help clarify the structure of astrophysically-important nuclei. We are also poised to begin studies with doubly-magic 132Sn. The experimental methods and results are discussed.

  15. Recent Astrophysical Studies with Exotic Beams at ORNL

    International Nuclear Information System (INIS)

    Bardayan, Daniel W.

    2006-01-01

    The availability of exotic beams has produced great opportunities for advances in our understanding of the nucleosynthesis occurring in stellar burning and stellar explosions such as novae, X-ray bursts, and supernovae. In these extreme environments, synthesized radioactive nuclei can undergo subsequent nuclear processing before they decay, and thus to understand these events, we must understand reaction rates involving radioactive nuclei. At the ORNL Holi led Radioactive Ion Beam Facility (HRIBF), we have made several recent measurements using proton-rich beams such as 18F and 7Be and neutron-rich beams such as 82Ge and 84Se that help clarify the structure of astrophysically-important nuclei. We are also poised to begin studies with doubly-magic 132Sn. The experimental methods and results are discussed.

  16. Nuclear data for structural materials of fission and fusion reactors

    International Nuclear Information System (INIS)

    Goulo, V.

    1989-06-01

    The document presents the status of nuclear reaction theory concerning optical model development, level density models and pre-equilibrium and direct processes used in calculation of neutron nuclear data for structural materials of fission and fusion reactors. 6 refs

  17. Update on nuclear structure effects in light muonic atoms

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Oscar Javier, E-mail: javierh@triumf.ca; Dinur, Nir Nevo; Ji, Chen; Bacca, Sonia [TRIUMF (Canada); Barnea, Nir [The Hebrew University, Racah Institute of Physics (Israel)

    2016-12-15

    We present calculations of the nuclear structure corrections to the Lamb shift in light muonic atoms, using state-of-the-art nuclear potentials. We outline updated results on finite nucleon size contributions.

  18. Systems with N correlated fermions. Mean-field models for nuclear structures and other N-body systems

    International Nuclear Information System (INIS)

    Grasso, M.

    2009-10-01

    This document is a summary of the author's research activities whose common topic is the N-body problem. The first chapter introduces the N-body issue through models based on the mean-field theory and on the Hartree-Fock-Bogoliubov equations. The second chapter presents the understanding of exotic nuclei features within the mean-field approach. Exotic phenomena like nuclear bubble structure, pairing correlations and pairing violations, giant neutron halos, non-standard terms in the Skyrme interactions are reviewed. The chapter 3 is dedicated to some extensions of the RPA (random phase approximation). For instance the computation of the shell structure far from the stability valley requires a more accurate assessment of the energy of the individual states through the introduction of a particle-vibration coupling. Different RPA extensions are described: first the self-consistent extension enlarged beyond particle-hole configurations, then the boson-mapping-based extension in a 3-level Lipkin model and also the second random-phase approximation. The chapter 4 gathers some studies concerning ultra-cold gases of trapped atoms. These systems are the only structures that allow the study of the correlations associated to superfluidity in terms of interaction intensity, temperature or system size. The mean-field approach is adequate for these studies. The last chapter draws a perspective for the mean-field-based models, their limits are assessed and ways of improvement are proposed. (A.C.)

  19. Investigation of the nuclear matter density distributions of the exotic 12Be,14Be and 8B nuclei by elastic proton scattering in inverse kinematics

    International Nuclear Information System (INIS)

    Ilieva, Stoyanka

    2008-01-01

    In the current experiment, the differential cross sections for proton elastic scattering on the isotopes 7,9,10,11,12,14 Be and 8 B were measured. As results from the experiment, the absolute differential cross sections dσ/dt as a function of the four momentum transfer t were obtained. In this work the differential cross sections for elastic p- 12 Be, p- 14 Be and p- 8 B scattering at low t (t≤0.05(GeV/c) 2 ) are presented. The measured cross sections were analyzed within the Glauber multiple-scattering theory using different density parameterizations, and the nuclear matter density distributions and radii of the investigated isotopes were determined. The determined rms matter radius is 3.11±0.04±0.13 fm. In the case of the 12 Be nucleus the results showed an extended matter distribution as well. For this nucleus a matter radius of 2.82±0.03±0.12 fm was determined. An interesting result is that the free 12 Be nucleus behaves differently from the core of 14 Be and is much more extended than it. Preliminary experimental results for the isotope 8 B are also presented. An extended matter distribution was obtained (though much more compact as compared to the neutron halos). A proton halo structure was observed for the first time with the proton elastic scattering method. The deduced matter radius is 2.60±0.02±0.26 fm. Results from the feasibility studies of the EXL detector setup, performed at the present ESR storage ring, are presented. (orig.)

  20. Nuclear structure and neutrino-nucleus interaction

    International Nuclear Information System (INIS)

    Krmpotic, Francisco

    2011-01-01

    Recent years have witnessed an intense experimental and theoretical activity oriented towards a better comprehension of neutrino nucleus interaction. While the main motivation for this task is the demand coming from oscillation experiments in their search for a precise determination of neutrino properties, the relevance of neutrino interaction with matter is more wide-ranging. It is imperative for astrophysics, hadronic and nuclear physics, and physics beyond the standard model. The experimental information on neutrino induced reactions is rapidly growing, and the corresponding theoretical description is a challenging proposition, since the energy scales of interest span a vast region, going from few MeV for solar neutrinos, to tens of MeV for the interpretation of experiments with the muon and pion decay at rest and the detection of neutrinos coming from the core collapse of supernova, and to hundreds of MeV or few GeV for the detection of atmospheric neutrinos, and for the neutrino oscillation program of the MiniBooNE experiment. The presence of neutrinos, being chargeless particles, can only be inferred by detecting the secondary particles created in colliding and interacting with the matter. Nuclei are often used as neutrino detectors, and in particular 12 C which is a component of many scintillator detectors. Thus, the interpretation of neutrino data heavily relies on detailed and quantitative knowledge of the features of the neutrino-nucleus interaction. The nuclear structure methods used in the evaluation of the neutrino-nucleus cross section are reviewed. Detailed comparison between the experimental and theoretical results establishes benchmarks needed for verification and/or parameter adjustment of the nuclear models. Having a reliable tool for such calculation is of great importance in a variety of applications, such as the description of the r-process nucleosynthesis. (author)

  1. Studies of exotic nuclei

    International Nuclear Information System (INIS)

    Angelique, J.C.; Orr, N.A.

    1997-01-01

    The study of the nuclei far off stability valley is of much interest for testing the nuclear models established for the stable nuclei but also for astrophysics to understand the nucleosynthesis. Experiments aim to measure the mass and lifetime, to build the decay schemes and also to study the structure and the properties of these nuclei. The radioactive beam group focused its research on light neutron-rich nuclei having a halo neutron structure. Mass measurements in N ∼ Z nuclei namely in A ∼ 60-80 proton-rich nuclei, important for understanding the rp process, are mentioned, as well as in nuclei in the 100 Sn region. In the newly obtained 26 O and 28 O nuclei the lifetimes, the probabilities of emission of one for more neutrons were determined. The data analysis has permitted to determine also for the first time the lifetimes of 27,29 F and 30 Ne. Studies of nuclei in the 100 Sn region, near the proton drip line in the ground and isomeric states are now under way. The spectroscopy (energy levels, gamma emissions, etc.) of the neutron-rich nuclei produced by the 36 S fragmentation has been carried out in 31 Ne, 17 B and 29 F. Studies by Coulomb excitation of the 2 + excited states and associated probability B (E2) in O, Ne, Ni and Zn are now analysed

  2. Nuclear structure research. Annual progress report

    International Nuclear Information System (INIS)

    Wood, J.L.

    1996-01-01

    The most significant development this year has been the realization that EO transition strength is a fundamental manifestation of nuclear mean-square charge radius differences. Thus, EO transitions provide a fundamental signature for shape coexistence in nuclei. In this sense, EO transitions are second only to E2 transitions for signaling (quadrupole) shapes in nuclei and do so when shape differences occur. A major effort has been devoted to the review of EO transitions in nuclei. Experiments have been carried out or are scheduled at: ATLAS/FMA (α decay of very neutron-deficient Bi isotopes); MSU/NSCL (β decay of 56 Cu); and HRIBF/RMS (commissioning of tape collector, internal conversion/internal-pair spectrometer; β decay of 58 Cu). A considerable effort has been devoted to planning the nuclear structure physics that will be pursued using HRIBF. Theoretical investigations have continued in collaboration with Prof. K. Heyde, Prof. D.J. Rowe, Prof. J.O. Rasmussen, and Prof. P.B. Semmes. These studies focus on shape coexistence and particle-core coupling

  3. Doubly charmed exotic mesons: A gift of nature?

    Energy Technology Data Exchange (ETDEWEB)

    Carames, T.F. [Departamento de Fisica Fundamental, Universidad de Salamanca, E-37008 Salamanca (Spain); Valcarce, A., E-mail: valcarce@usal.e [Departamento de Fisica Fundamental, Universidad de Salamanca, E-37008 Salamanca (Spain); Vijande, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Valencia (UV) and IFIC (UV-CSIC), Valencia (Spain)

    2011-05-16

    We study doubly charmed exotic states by solving the scattering problem of two D mesons. Our results point to the existence of a stable isoscalar doubly charmed meson with quantum numbers (I)J{sup P}=(0)1{sup +}. We perform a thorough comparison to the results obtained within the hyperspherical harmonic formalism. Such exotic states could be measured at LHC and RHIC. Their experimental observation would, for the first time, confirm the contribution of multiquark structures to hadron spectroscopy.

  4. Compilations and evaluations of nuclear structure and decay data

    International Nuclear Information System (INIS)

    Lorenz, A.

    1977-03-01

    This is the second issue of a report series on published and to-be-published compilations and evaluations of nuclear structure and decay (NSD) data. This compilation of compilations and evaluations is designed to keep the nuclear scientific community informed of the availability of compiled or evaluated NSD data, and contains references to laboratory reports, journal articles and books containing selected compilations and evaluations. It excludes references to ''mass-chain'' evaluations normally published in the ''Nuclear Data Sheets'' and ''Nuclear Physics''. The material contained in this compilation is sorted according to eight subject categories: general compilations; basic isotopic properties; nuclear structure properties; nuclear decay processes; half-lives, energies and spectra; nuclear decay processes: gamma-rays; nuclear decay processes: fission products; nuclear decay processes: (others); atomic processes

  5. Nuclear structure physics at RI beam factory

    International Nuclear Information System (INIS)

    Otsuka, Takaharu

    1998-01-01

    The nuclear structure physics is becoming extremely interesting owing to recent development of RI beam factories. Among various interesting developments in this field, I will focus upon two subjects. One is the breaking of the usual magic numbers in unstable nuclei, and the other is the invention of a new method for quantum many-body problems: Quantum Monte Carlo diagonalization method (QMCD). For the first subject, I will discuss the vanishing of N=8 and 20 magic numbers in 11 Li and 32 Mg, respectively. For the latter, I will present brief description of the theory and results of some applications including the one to 64 Ge, a proton-rich unstable nucleus. (author)

  6. The TRIUMF nuclear structure program and TIGRESS

    Science.gov (United States)

    Garrett, P. E.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Boston, H. C.; Chakrawarthy, R. S.; Churchman, R.; Cline, D.; Cooper, R. J.; Cross, D.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T.; Finlay, P.; Gagnon, K.; Gallant, A. T.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Hackman, G.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Kulp, W. D.; Leach, K. G.; Lee, G.; Leslie, J. R.; Maharaj, R.; Martin, J.-P.; Mattoon, C.; Mills, W. J.; Morton, A. C.; Nelson, L.; Newman, O.; Nolan, P. J.; Padilla-Rodal, E.; Pearson, C. J.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Ruiz, C.; Sarazin, F.; Schumaker, M. A.; Scraggs, D. P.; Strange, M. D.; Subramanian, M.; Svensson, C. E.; Waddington, J. C.; Wan, J.; Whitbeck, A.; Williams, S. J.; Wood, J. L.; Wong, J. C.; Wu, C. Y.; Zganjar, E. F.

    2007-08-01

    The isotope separator and accelerator (ISAC) facility located at the TRIUMF laboratory in Vancouver, Canada, is one of the world's most advanced isotope separator on-line-type radioactive ion beam facilities. An extensive γ-ray spectroscopy programme at ISAC is centred around two major research facilities: (i) the 8π γ-ray spectrometer for β-delayed γ-ray spectroscopy experiments with the low-energy beams from ISAC-I, and (ii) the next generation TRIUMF-ISAC gamma-ray escape suppressed spectrometer (TIGRESS) for in-beam experiments with the accelerated radioactive-ion beams. An overview of these facilities and recent results from the diverse programme of nuclear structure and fundamental interaction studies they support is presented.

  7. Aging of nuclear safety related concrete structures

    International Nuclear Information System (INIS)

    Cerny, R.; Vydra, V.; Toman, J.; Vodak, F.

    1994-01-01

    An analysis of aging processes in nuclear-safety-related concrete structures (NSRCS) is presented. The major environmental stressor and aging factors affecting the performance of NSRCS are summarized, as are drying and plastic shrinkage, expansion of water during the freeze-thaw cycle, water passing through cracks dissolving or leaching the soluble calcium hydroxide, attack of acid rain and ground water, chemical reactions between particular aggregates and the alkaline solution within cement paste, reaction of calcium hydroxide in cement paste hydration products with atmospheric carbon dioxide, and physical radiation effects of neutrons and gamma radiation. The current methods for aging management in NSRCS are analyzed and evaluated. A new treatment is presented for the monitoring, evaluation and prediction of aging processes, consisting in a combination of theoretical methods, laboratory experiments, in-situ measurements and numerical simulations. 24 refs

  8. ENAM'04 Fourth International Conference on Exotic Nuclei and Atomic Masses

    International Nuclear Information System (INIS)

    Gross, C. J.; Nazarewicz, W.; Rykaczewski, K. P.

    2005-01-01

    The conference can trace its origins to the 1950s and 1960s with the Atomic Mass and Fundamental Constants (AMCO) and the Nuclei Far From Stability (NFFS) series of conferences. Held jointly in 1992, the conferences officially merged in 1995 and the fourth conference was held at Callaway Gardens in Pine Mountain, GA and was organized by the Physics Division at Oak Ridge National Laboratory. The conference covered a broad list of topics consisting of a series of invited and contributed presentation highlighting recent research in the following fields: Atomic masses, nuclear moments, and nuclear radii; Forms of radioactivity; Nuclear structure, nuclei at the drip lines, cluster phenomena; Reactions with radioactive ion beams; Nuclear astrophysics; Fundamental symmetries and interactions; Heaviest elements and fission; Radioactive ion beam production and experimental developments; Applications of exotic nuclei

  9. Nuclear structure and heavy-ion fusion

    International Nuclear Information System (INIS)

    Stokstad, R.G.

    1980-10-01

    A series of lectures is presented on experimental studies of heavy-ion fusion reactions with emphasis on the role of nuclear structure in the fusion mechanism. The experiments considered are of three types: the fusion of lighter heavy ions at subcoulomb energies is studied with in-beam γ-ray techniques; the subbarrier fusion of 16 O and 40 Ar with the isotopes of samarium is detected out of beam by x-radiation from delayed activity; and measurements at very high energies, again for the lighter ions, employ direct particle identification of evaporation residues. The experimental data are compared with predictions based on the fusion of two spheres with the only degree of freedom being the separation of the centers, and which interact via potentials that vary smoothly with changes in the mass and charge of the projectile and target. The data exhibit with the isotopes of samarium, a portion of these deviations can be understood in terms of the changing deformation of the target nucleus, but an additional degree of freedom such as neck formation appears necessary. The results on 10 B + 16 O and 12 C + 14 N → 26 Al at high bombarding energies indicate a maximum limiting angular momentum characteristic of the compound nucleus. At lower energies the nuclear structure of the colliding ion seems to affect strongly the cross section for fusion. Measurements made at subbarrier energies for a variety of projectile-target combinations in the 1p and 2s - 1d shell also indicate that the valence nucleons can affect the energy dependence for fusion. About half the systems studied so far have structureless excitation functions which follow a standard prediction. The other half exhibit large variations from this prediction. The possible importance of neutron transfer is discussed. The two-center shell model appears as a promising approach for gaining a qualitative understanding of these phenomena. 95 references, 52 figures, 1 table

  10. [Electromagnetic studies of nuclear structure and reactions

    International Nuclear Information System (INIS)

    1992-01-01

    The experimental goals are focused on developing an understanding of strong interactions and the structure of hadronic systems by determination of the electromagnetic response; these goals will be accomplished through coincidence detection of final states. Nuclear modeling objectives are to organize and interpret the data through a consistent description of a broad spectrum of reaction observables; calculations are performed in a nonrelativistic diagrammatic framework as well as a relativistic QHD approach. Work is described according to the following arrangement: direct knockout reactions (completion of 16 O(e,e'p), 12 C(e,e'pp) progress, large acceptance detector physics simulations), giant resonance studies (intermediate-energy experiments with solid-state detectors, the third response function in 12 C(e,e'p 0 ) and 16 O(e,e'p 0 ), comparison of the 12 C(e, e'p 0 ) and 16 O(e,e'p 3 ) reactions, quadrupole strength in the 16 O(e,e'α 0 ) reaction, quadrupole strength in the 12 C(e,e'α) reaction, analysis of the 12 C(e,e'p 1 ) and 16 O(e,e'p 3 ) angular distributions, analysis of the 40 Ca(e,e'x) reaction at low q, analysis of the higher-q 12 C(e,e'x) data from Bates), models of nuclear structure (experimental work, Hartree-Fock calculations, phonon excitations in spherical nuclei, shell model calculations, variational methods for relativistic fields), and instrumentation development efforts (developments at CEBAF, CLAS contracts, BLAST developments)

  11. International conference: Features of nuclear excitation states and mechanisms of nuclear reactions. 51. Meeting on nuclear spectroscopy and nuclear structure. The book of abstracts

    International Nuclear Information System (INIS)

    2001-01-01

    Results of the LI Meeting on Nuclear Spectroscopy and Nuclear Structure are presented. Properties of excited states of atomic nuclei and mechanisms of nuclear reactions are considered. Studies on the theory of nucleus and fundamental interactions pertinent to experimental study of nuclei properties and mechanisms of nuclear reactions, technique and methods of experiment, application of nuclear-physical method, are provided [ru

  12. Nuclear Reaction and Structure Databases of the National Nuclear Data Center

    International Nuclear Information System (INIS)

    Pritychenko, B.; Arcilla, R.; Herman, M. W.; Oblozinsky, P.; Rochman, D.; Sonzogni, A. A.; Tuli, J. K.; Winchell, D. F.

    2006-01-01

    The National Nuclear Data Center (NNDC) collects, evaluates, and disseminates nuclear physics data for basic research and applied nuclear technologies. In 2004, the NNDC migrated all databases into modern relational database software, installed new generation of Linux servers and developed new Java-based Web service. This nuclear database development means much faster, more flexible and more convenient service to all users in the United States. These nuclear reaction and structure database developments as well as related Web services are briefly described

  13. Nuclear enhanced power corrections to DIS structure functions

    OpenAIRE

    Guo, Xiaofeng; Qiu, Jianwei; Zhu, Wei

    2001-01-01

    We calculate nuclear enhanced power corrections to structure functions measured in deeply inelastic lepton-nucleus scattering in Quantum Chromodynamics (QCD). We find that the nuclear medium enhanced power corrections at order of $O(\\alpha_s/Q^2)$ enhance the longitudinal structure function $F_L$, and suppress the transverse structure function $F_1$. We demonstrate that strong nuclear effects in $\\sigma_A/\\sigma_D$ and $R_A/R_D$, recently observed by HERMES Collaboration, can be explained in ...

  14. High-spin nuclear structure studies with radioactive ion beams

    International Nuclear Information System (INIS)

    Baktash, C.

    1992-01-01

    Two important developments in the sixties, namely the advent of heavy-ion accelerators and fabrication of Ge detectors, opened the way for the experimental studies of nuclear properties at high angular momentum. Addition of a new degree of freedom, namely spin, made it possible to observe such fascinating phenomena as occurrences and coexistence of a variety of novel shapes, rise, fall and occasionally rebirth of nuclear collectivity, and disappearance of pairing correlations. Today, with the promise of development of radioactive ion beams (RIB) and construction of the third-generation Ge-detection systems (GAMMASPHERE and EUROBALL), nuclear physicists are poised to explore new and equally fascinating phenomena that have been hitherto inaccessible. With the addition of yet another dimension, namely the isospin, they will be able to observe and verify predictions for exotic shapes as varied as rigid triaxiality, hyperdeformation and triaxial-octupole shapes, or to investigate the T=O pairing correlations. In this paper, the author reviews, separately for neutron-deficient and neutron-rich nuclei, these and a few other new high-spin physics opportunities that may be realized with RIB. Following this discussion, a list of the beam species, intensities and energies that are needed to fulfill these goals is presented. The paper concludes with a description of the experimental techniques and instrumentations that are required for these studies

  15. Aging of concrete structures in nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.; Pland, C.B.; Arndt, E.G.

    1991-01-01

    The Structural Aging (SAG) Program, sponsored by the US Nuclear Regulatory Commission (USNRC) and conducted by the Oak Ridge National Laboratory (ORNL), had the overall objective of providing the USNRC with an improved basis for evaluating nuclear power plant structures for continued service. The program consists of three technical tasks: materials property data base, structural component assessment/repair technology, and quantitative methodology for continued service determinations. Major accomplishments under the SAG Program during the first two years of its planned five-year duration have included: development of a Structural Materials Information Center and formulation of a Structural Aging Assessment Methodology for Concrete Structures in Nuclear Power Plants. 9 refs

  16. [Studies of nuclear structure using neutrons and charged particles

    International Nuclear Information System (INIS)

    1989-01-01

    This report contains brief discussions on nuclear research done at Triangle Universities Nuclear Laboratory. The major categories covered are: Fundamental symmetries in the nucleus; Dynamics in very light nuclei; D states in light nuclei; Nucleon-nucleus interactions; Nuclear structure and reactions; and Instrumentation and development

  17. Nuclear Cartography: Patterns in Binding Energies and Subatomic Structure

    Science.gov (United States)

    Simpson, E. C.; Shelley, M.

    2017-01-01

    Nuclear masses and binding energies are some of the first nuclear properties met in high school physics, and can be used to introduce radioactive decays, fusion, and fission. With relatively little extension, they can also illustrate fundamental concepts in nuclear physics, such as shell structure and pairing, and to discuss how the elements…

  18. Two-level convolution formula for nuclear structure function

    Science.gov (United States)

    Ma, Boqiang

    1990-05-01

    A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions.

  19. Two-level convolution formula for nuclear structure function

    International Nuclear Information System (INIS)

    Ma Boqiang

    1990-01-01

    A two-level convolution formula for the nuclear structure function is derived in considering the nucleus as a composite system of baryon-mesons which are also composite systems of quark-gluons again. The results show that the European Muon Colaboration effect can not be explained by the nuclear effects as nucleon Fermi motion and nuclear binding contributions

  20. Nuclear utility structure. Use of nuclear service companies

    International Nuclear Information System (INIS)

    Ring, L.E.

    1980-01-01

    The feasibility of utilities incorporating service companies to construct and maintain nuclear power plants is analyzed. Responsibilities of the service companies and the public opinion of the concept are discussed

  1. Tornado-resistance design for the nuclear safety structure of Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Xia Zufeng.

    1987-01-01

    The primary design consideration of anti-tornado of the nuclear safety structure of Qinshan Nuclear Power Plant is briefly presented. It mainly includes estimating the probability of tornado arising in the site, ascertaining the design requirments of the anti-tornado structures and deciding the tornado load acted on the structures

  2. BROOKHAVEN: Glueballs, hybrids and exotics

    Energy Technology Data Exchange (ETDEWEB)

    Chung, S. -U.

    1988-12-15

    A workshop at Brookhaven from August 29 to September 1 looked at the current status of hadron spectroscopy beyond the realm of states conventionally built up from quarks and discussed future experimental effort to explore such exotic states.

  3. Nuclear structure and radioactive decay resources at the US National Nuclear Data Center

    International Nuclear Information System (INIS)

    Sonzogni, A.A.; Burrows, T.W.; Pritychenko, B.; Tuli, J.K.; Winchell, D.F.

    2008-01-01

    The National Nuclear Data Center has a long tradition of evaluating nuclear structure and decay data as well as offering tools to assist in nuclear science research and applications. With these tools, users can obtain recommended values for nuclear structure and radioactive decay observables as well as links to the relevant articles. The main databases or tools are ENSDF, NSR, NuDat and the new Endf decay data library. The Evaluated Nuclear Structure Data File (ENSDF) stores recommended nuclear structure and decay data for all nuclei. ENSDF deals with properties such as: -) nuclear level energies, spin and parity, half-life and decay modes, -) nuclear radiation energy and intensity for different types, -) nuclear decay modes and their probabilities. The Nuclear Science References (NSR) is a bibliographic database containing nearly 200.000 nuclear sciences articles indexed according to content. About 4000 are added each year covering 80 journals as well as conference proceedings and laboratory reports. NuDat is a software product with 2 main goals, to present nuclear structure and decay information from ENSDF in a user-friendly way and to allow users to execute complex search operations in the wealth of data contained in ENSDF. The recently released Endf-B7.0 contains a decay data sub-library which has been derived from ENSDF. The way all these databases and tools have been offered to the public has undergone a drastic improvement due to advancements in information technology

  4. The Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas jet target

    International Nuclear Information System (INIS)

    Chipps, K.A.; Greife, U.; Bardayan, D.W.; Blackmon, J.C.; Kontos, A.; Linhardt, L.E.; Matos, M.; Pain, S.D.; Pittman, S.T.; Sachs, A.; Schatz, H.; Schmitt, K.T.; Smith, M.S.; Thompson, P.

    2014-01-01

    New radioactive ion beam (RIB) facilities will push further away from stability and enable the next generation of nuclear physics experiments. Of great importance to the future of RIB physics are scattering, transfer, and capture reaction measurements of rare, exotic, and unstable nuclei on light targets such as hydrogen and helium. These measurements require targets that are dense, highly localized, and pure. Targets must also accommodate the use of large area silicon detector arrays, high-efficiency gamma arrays, and heavy ion detector systems to efficiently measure the reaction products. To address these issues, the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) Collaboration has designed, built, and characterized a supersonic gas jet target, capable of providing gas areal densities on par with commonly used solid targets within a region of a few millimeters diameter. Densities of over 5×10 18 atoms/cm 2 of helium have been achieved, making the JENSA gas jet target the most dense helium jet achieved so far

  5. New possibilities for exotic hadrons

    International Nuclear Information System (INIS)

    Lipkin, H.J.

    1987-01-01

    New theoretical ideas and experimental evidence for exotic hadrons are presented. A new exciting candidate is an anticharmed baryon; i.e., a bound state of a nucleon and an F (now called D 3 ). New experimental evidence for four-quark exotic mesons presented at this conference is discussed. The confusion in the E-iota region and the pseudoscalar spectrum still await further experimental clarification

  6. Exotic nuclei in self-consistent mean-field models

    International Nuclear Information System (INIS)

    Bender, M.; Rutz, K.; Buervenich, T.; Reinhard, P.-G.; Maruhn, J. A.; Greiner, W.

    1999-01-01

    We discuss two widely used nuclear mean-field models, the relativistic mean-field model and the (nonrelativistic) Skyrme-Hartree-Fock model, and their capability to describe exotic nuclei with emphasis on neutron-rich tin isotopes and superheavy nuclei. (c) 1999 American Institute of Physics

  7. Investigations of nuclear structure and nuclear reactions induced by complex projectiles

    International Nuclear Information System (INIS)

    Sarantites, D.G.

    1990-01-01

    This report discusses research in the following areas: nuclear structure; fusion reactions near and below the barrier; incomplete fusion and fragmentation reactions; and instrumentation and analysis. (LSP)

  8. Experiments with relativistic exotic nuclei at the FRS

    International Nuclear Information System (INIS)

    Geissel, H.

    1994-11-01

    The concept and experimental programme of the secondary nuclear beam facility BRENDA at GSI is presented. The central part of BRENDA is the magnetic spectrometer FRS providing spatially separated monoisotopic exotic beams of all elements up to uranium. The FRS as a versatile magnetic spectrometer for experiments with heavy ions in the energy range of (0.1-2) A.GeV has been used to study peripheral nuclear collisions from oxygen up to uranium projectiles. In the uranium experiments we discovered that projectile fission is a powerful tool to investigate new neutron-rich fission fragments. In the medium mass region we have identified the doubly magic nucleus 100 Sn and measured its half-life. Light halo nuclei have been studied in kinematically complete experiments with the FRS in combination with the dipole magnet ALADIN, and the neutron detector LAND. The FRS combined with the storage and cooler ring ESR offers new precision experiments, e.g., direct mass measurements, decay studies of highly-charged nuclei, or nuclear structure studies in inverse kinematics. (orig.)

  9. Some highlights of the Daresbury nuclear structure programme

    International Nuclear Information System (INIS)

    Gelletly, W.

    1984-01-01

    The paper concerns the nuclear structure programme at the Daresbury laboratory, United Kingdom. A description is given of the Nuclear Structure Facility (NSF), along with its principal properties and design features. Some of the latest equipment used at the NSF is discussed, including the isotope separator, recoil separator, magnetic spectrometer and gamma-ray detectors. Uses of this equipment at the NSF to study the nuclear properties at high angular momentum and nuclei far from stability, are also described. (U.K.)

  10. Nuclear structure of light Ca and heavy Cr isotopes

    International Nuclear Information System (INIS)

    Buerger, A.

    2007-01-01

    In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus 36 Ca which was produced in a knockout reaction from a radioactive 37 Ca beam. For 36 Ca, the excitation energy of the first 2 + state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the predicted value. A remaining difference might be due to emission of protons which cannot be detected with the present experimental setup. Both the branching ratio and the large excitation energy are compatible with a large N=16 gap in 36 Ca that leads to relatively pure configurations both in the ground state and the excited 2 + state. As a by-product of the experiment, two excitation energies in the T=2 nuclei 32 Ar and 28 S have been confirmed, and two γ-ray transitions have been observed for the first time in 37 Ca. While the mirror energy differences in the T=2 pairs 36 Ca- 36 S, 32 Ar- 32 Si, and 28 S- 28 Mg can be reproduced in shell model calculations using a modified USD interaction, these modifications are not sufficient to explain the mirror energy differences for the pair 37 Ca- 37 Cl. In the heavy Cr isotopes, new experimental evidence for a sub-shell closure at N=32 was found in a measurement of B(E2) values using high-energy Coulomb excitation of radioactive beams. Prior to this experiment, the assumption of a

  11. Nuclear structure of light Ca and heavy Cr isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Buerger, A.

    2007-07-01

    In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the predicted value. A remaining difference might be due to emission of protons which cannot be detected with the present experimental setup. Both the branching ratio and the large excitation energy are compatible with a large N=16 gap in {sup 36}Ca that leads to relatively pure configurations both in the ground state and the excited 2{sup +} state. As a by-product of the experiment, two excitation energies in the T=2 nuclei {sup 32}Ar and {sup 28}S have been confirmed, and two {gamma}-ray transitions have been observed for the first time in {sup 37}Ca. While the mirror energy differences in the T=2 pairs {sup 36}Ca-{sup 36}S, {sup 32}Ar-{sup 32}Si, and {sup 28}S-{sup 28}Mg can be reproduced in shell model calculations using a modified USD interaction, these modifications are not sufficient to explain the mirror energy differences for the pair {sup 37}Ca-{sup 37}Cl. In the heavy Cr isotopes, new experimental evidence for a sub-shell closure at N=32 was found in a measurement of B(E2) values using high

  12. Strategic disruption of nuclear pores structure, integrity and barrier for nuclear apoptosis.

    Science.gov (United States)

    Shahin, Victor

    2017-08-01

    Apoptosis is a programmed cell death playing key roles in physiology and pathophysiology of multi cellular organisms. Its nuclear manifestation requires transmission of the death signals across the nuclear pore complexes (NPCs). In strategic sequential steps apoptotic factors disrupt NPCs structure, integrity and barrier ultimately leading to nuclear breakdown. The present review reflects on these steps. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Proceedings of second national workshop on nuclear structure physics

    International Nuclear Information System (INIS)

    Chintalapudi, S.N.; Jain, A.K.

    1995-01-01

    The Second National Workshop on Nuclear Structure Physics was held at Calcutta during February 7-10 1995. The topics discussed have been quite broad based and covered many areas of nuclear structure physics and radiochemistry. Papers relevant to INIS are indexed separately

  14. Threedimensional imaging of organ structures by nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Waters, W.; Smolorz, J.; Wellner, U.

    1985-01-01

    A simple method for threedimensional imaging of organ structures is presented. The method is based on a special acquisition mode in a nuclear resonance tomograph, exciting layers of 20 cm thickness at different angulations. The display is done by cinematography (which is usually used in nuclear cardiology) projecting the structures in a rotating movement. (orig.) [de

  15. Changes in Nuclear Structure During Wheat Endosperm Development

    NARCIS (Netherlands)

    Wegel, E.

    2005-01-01

    This thesis is an investigation into the structure of wheat endosperm nuclei starting with nuclear divisions and migration during syncytium formation followed by the development of nuclear shape and positioning of chromosome territories and ending with changes in subchromosomal structure during the

  16. Direct observation of an isomeric state in {sup 98}Rb and nuclear properties of exotic rubidium isotopes measured by laser spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Procter, T.J.; Garnsworthy, A.B.; Levy, C.D.P.; Pearson, M.R. [TRIUMF, Vancouver, British Columbia (Canada); Behr, J.A.; Dilling, J. [TRIUMF, Vancouver, British Columbia (Canada); University of British Columbia, Department of Physics, Vancouver, British Columbia (Canada); Billowes, J. [The University of Manchester, School of Physics and Astronomy, Manchester (United Kingdom); Buchinger, F.; Crawford, J.E.; Leary, A.; Shelbaya, O.; Al Tamimi, W. [McGill University, Physics Department, Montreal, Quebec (Canada); Cheal, B. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Mane, E. [TRIUMF, Vancouver, British Columbia (Canada); Ministry of External Relations, Rio Bianco Institute, Brasilia (Brazil); Stolz, M. [Technische Universitaet Berlin, Berlin (Germany); Voss, A. [TRIUMF, Vancouver, British Columbia (Canada); University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland)

    2015-02-01

    Fast-beam collinear laser spectroscopy experiments on rubidium have been performed at the ISAC radioactive ion beam facility at TRIUMF. Most recently, the neutron-rich {sup 98}Rb isotope has been studied for the investigation of shape coexistence. Two long-lived nuclear states in {sup 98}Rb have been clearly observed for the first time: a low-spin state, assigned a spin of I = 0, and a high-spin state. The high-spin state is tentatively assigned a spin of I = 3 based on this analysis in combination with gamma decay results. The measured nuclear properties of the two states are presented, alongside unpublished values of the neutron-deficient isotopes investigated previously. The mean-square charge radii of both states in {sup 98}Rb are observed to continue along the isodeformation line present after the N = 60 onset of deformation. (orig.)

  17. Random matrices and chaos in nuclear physics: Nuclear structure

    International Nuclear Information System (INIS)

    Weidenmueller, H. A.; Mitchell, G. E.

    2009-01-01

    Evidence for the applicability of random-matrix theory to nuclear spectra is reviewed. In analogy to systems with few degrees of freedom, one speaks of chaos (more accurately, quantum chaos) in nuclei whenever random-matrix predictions are fulfilled. An introduction into the basic concepts of random-matrix theory is followed by a survey over the extant experimental information on spectral fluctuations, including a discussion of the violation of a symmetry or invariance property. Chaos in nuclear models is discussed for the spherical shell model, for the deformed shell model, and for the interacting boson model. Evidence for chaos also comes from random-matrix ensembles patterned after the shell model such as the embedded two-body ensemble, the two-body random ensemble, and the constrained ensembles. All this evidence points to the fact that chaos is a generic property of nuclear spectra, except for the ground-state regions of strongly deformed nuclei.

  18. Statistical spectroscopic studies in nuclear structure physics

    International Nuclear Information System (INIS)

    Halemane, T.R.

    1979-01-01

    The spectral distribution theory establishes the centroid and width of the energy spectrum as quantities of fundamental importance and gives credence to a geometry associated with averages of the product of pairs of operators acting within a model space. Utilizing this fact and partitioning the model space according to different group symmetries, simple and physically meaningful expansions are obtained for the model interactions. In the process, a global measure for the goodness of group symmetries is also developed. This procedure could eventually lead to a new way of constructing model interactions for nuclear structure studies. Numerical results for six (ds)-shell interactions and for scalar-isospin, configuration-isospin, space symmetry, supermultiplet and SU(e) x SU(4) group structures are presented. The notion of simultaneous propagation of operator averages in the irreps of two or more groups (not necessarily commuting) is also introduced. The non-energy-weighted sum rule (NEWSR) for electric and magnetic multipole excitations in the (ds)-shell nuclei 20 Ne, 24 Mg, 28 Si, 32 S, and 36 Ar are evaluated. A generally applicable procedure for evaluating the eigenvalue bound to the NEWSR is presented and numerical results obtained for the said excitations and nuclei. Comparisons are made with experimental data and shell-model results. Further, a general theory is given for the linear-energy-weighted sum rule (LEWSR). When the Hamiltonian is one-body, this has a very simple form (expressible in terms of occupancies) and amounts to an extension of the Kurath sum rule to other types of excitations and to arbitrary one-body Hamiltonians. Finally, we develop a statistical approach to perturbation theory and inverse-energy-weighted sum rules, and indicate some applications

  19. Nuclear structure research. Annual progress report

    International Nuclear Information System (INIS)

    Wood, J.L.

    1995-01-01

    The most significant development this year has been the realization of a method for estimating EO transition strength in nuclei and the prediction that the de-excitation (draining) of superdeformed bands must take place, at least in some cases, by strong EO transitions. A considerable effort has been devoted to planning the nuclear structure physics that will be pursued using the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge. A significant effort has been devoted to HRIBF target development. This is a critical component of the HRIBF project. Exhaustive literature searches have been made for a variety of target materials with emphasis on thermodynamic properties. Vapor pressure measurements have been carried out. Experimental data sets for radioactive decays in the very neutron-deficient Pr-Eu and Ir-Tl regions have been under analysis. These decay schemes constitute parts of student Ph.D. theses. These studies are aimed at elucidating the onset of deformation in the Pr-Sm region and the characteristics of shape coexistence in the Ir-Bi region. Further experiments on shape coexistence in the neutron-deficient Ir-Bi region are planned using α decay studies at the FMA at ATLAS. The first experiment is scheduled for later this year

  20. Nuclear matter in neutron star crust

    International Nuclear Information System (INIS)

    Kido, Toshihiko; Maruyama, Toshiki; Chiba, Satoshi; Niita, Koji

    2000-01-01

    Properties of nuclear matter below the nuclear saturation density is analyzed by numerical simulations with the periodic boundary condition. The equation of state at these densities is softened by the formation of cluster(s) internal density of which is nearly equal to the saturation density. The structure of nuclear matter shows some exotic shapes with variation of the density. Furthermore, it is found that the symmetry parameter a sym (ρ) is not a linear function of density at low density region. (author)

  1. Safety classification of nuclear power plant systems, structures and components

    International Nuclear Information System (INIS)

    1992-01-01

    The Safety Classification principles used for the systems, structures and components of a nuclear power plant are detailed in the guide. For classification, the nuclear power plant is divided into structural and operational units called systems. Every structure and component under control is included into some system. The Safety Classes are 1, 2 and 3 and the Class EYT (non-nuclear). Instructions how to assign each system, structure and component to an appropriate safety class are given in the guide. The guide applies to new nuclear power plants and to the safety classification of systems, structures and components designed for the refitting of old nuclear power plants. The classification principles and procedures applying to the classification document are also given

  2. Search for Exotic Strange Dibaryon in Relativistic Heavy Ion Collisions

    Institute of Scientific and Technical Information of China (English)

    GAO Chong-Shou

    2003-01-01

    The exotic strange dibaryon particle (ΩΩ)0+ with S = -6 can be produced in relativistic heavyioncollisions. The yields of this kind of exotic strange dibaryon particles can increase significantly soon as the formation ofQGP does exhibit after the collision. If there is no phase transition after the collision, the upper bound of the productionof this diomega can be estimated from the free hadronic gas model for nuclear matter. The relative yield ratio of diomegato deuteron is less than 0.000205, this means that if there is no QGP creation it is difficult to observe the production ofdiomega in relativistic heavy ion collisions.

  3. Search for Exotic Strange Dibaryon in Relativistic Heavy Ion Collisions

    Institute of Scientific and Technical Information of China (English)

    GAOChong-Shou

    2003-01-01

    The exotic strange dibaryon particle (ΩΩ)0+ with S = -6 can be produced in relativistic heavy ion collisions. The yields of this kind of exotic strange dibaryon particles can increase signitlcantly soon as the formation of QGP does exhibit after the collision. If there is no phase transition after the collision, the upper bound of the production of this diomega can be estimated from the free hadronic gas model for nuclear matter. The relative yield ratio of diomega to deuteron is less than 0.000205, this means that if there is no QGP creation it is difficult to observe the production of diomega in relativistic heavy ion collisions.

  4. Experiments with stored relativistic exotic nuclei

    International Nuclear Information System (INIS)

    Klepper, O.; Attallah, F.; Beckert, K.; Bosch, F.; Dolinskiy, A.; Eickhoff, H.; Franczak, B.; Franzke, B.; Geissel, H.; Hausmann, M.; Hellstroem, M.; Herfurth, F.; Kluge, H.-J.; Kozhuharov, C.; Muenzenberg, G.; Nolden, F.; Quint, W.; Tradon, T.; Reich, H.; Scheidenberger, C.; Schlitt, B.; Steck, M.; Suemmerer, K.; Vermeeren, L.; Winkler, M.; Winkler, Th.; Falch, M.; Kerscher, Th.; Loebner, K.E.G.; Fujita, Y.; Novikov, Yu.; Patyk, Z.; Stadlmann, J.; Wollnik, H.

    1999-01-01

    Beams of relativistic exotic nuclei were produced, separated and investigated with the combination of the fragment separator FRS and the storage ring ESR. The following experiments are presented: 1) Direct mass measurements of relativistic nickel and bismuth projectile fragments were performed using Schottky spectrometry. Applying electron cooling, the relative velocity spread of the circulating secondary nuclear beams of low intensity was reduced to below 10 -6 . The achieved mass resolving power of m/Δm = 6.5·10 5 (FWHM) in recent measurements represents an improvement by a factor of two compared to authors' previous experiments. The previously unknown masses of more than 100 proton-rich isotopes have been measured in the range of 54≤Z≤84. The results are compared with mass models and estimated values based on extrapolations of experimental values. 2) Exotic nuclei with half-lives shorter than the time required for electron cooling can be investigated by time-of-flight measurements with the ESR being operated in the isochronous mode. This novel experimental technique has been successfully applied in a first measurement with nickel fragments. A mass resolving power of m/Δm = 1.5·10 5 (FWHM) was achieved in this mode of operation. 3) Nuclear half-lives of stored and cooled bare projectile fragments have been measured to study the influence of the ionic charge state on the beta-decay probability

  5. Nuclear data newsletter. No. 20. Nuclear structure and decay data network

    International Nuclear Information System (INIS)

    1994-11-01

    This special issue of the Nuclear Data Newsletter dated November 1994 gives information on the Nuclear Structure and Decay Data (NSDD) Network established in 1974 under the auspices of the IAEA and comprising 17 laboratories and universities in 10 countries. The procedures for online access to US National Nuclear Data Center, NEA Data Bank in Paris and IAEA Nuclear Data Section in Vienna are presented

  6. Nuclear data newsletter. No. 20. Nuclear structure and decay data network

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-11-01

    This special issue of the Nuclear Data Newsletter dated November 1994 gives information on the Nuclear Structure and Decay Data (NSDD) Network established in 1974 under the auspices of the IAEA and comprising 17 laboratories and universities in 10 countries. The procedures for online access to US National Nuclear Data Center, NEA Data Bank in Paris and IAEA Nuclear Data Section in Vienna are presented.

  7. Exotic helium molecules

    International Nuclear Information System (INIS)

    Portier, M.

    2007-12-01

    We study the photo-association of an ultracold cloud of magnetically trapped helium atoms: pairs of colliding atoms interact with one or two laser fields to produce a purely long range 4 He 2 (2 3 S 1 -2 3 P 0 ) molecule, or a 4 He 2 (2 3 S 1 -2 3 S 1 ) long range molecule. Light shifts in one photon photo-association spectra are measured and studied as a function of the laser polarization and intensity, and the vibrational state of the excited molecule. They result from the light-induced coupling between the excited molecule, and bound and scattering states of the interaction between two metastable atoms. Their analysis leads to the determination of the scattering length a = (7.2 ± 0.6) ruling collisions between spin polarized atoms. The two photon photo-association spectra show evidence of the production of polarized, long-range 4 He 2 (2 3 S 1 -2 3 S 1 ) molecules. They are said to be exotic as they are made of two metastable atoms, each one carrying a enough energy to ionize the other. The corresponding lineshapes are calculated and decomposed in sums and products of Breit-Wigner and Fano profiles associated to one and two photon processes. The experimental spectra are fit, and an intrinsic lifetime τ = (1.4 ± 0.3) μs is deduced. It is checked whether this lifetime could be limited by spin-dipole induced Penning autoionization. This interpretation requires that there is a quasi-bound state close to the dissociation threshold in the singlet interaction potential between metastable helium atoms for the theory to match the experiment. (author)

  8. Transport Properties in Nuclear Pasta

    Science.gov (United States)

    Caplan, Matthew; Horowitz, Charles; Berry, Donald; da Silva Schneider, Andre

    2016-09-01

    At the base of the inner crust of neutron stars, where matter is near the nuclear saturation density, nuclear matter arranges itself into exotic shapes such as cylinders and slabs, called `nuclear pasta.' Lepton scattering from these structures may govern the transport properties of the inner crust; electron scattering from protons in the pasta determines the thermal and electrical conductivity, as well as the shear viscosity of the inner crust. These properties may vary in pasta structures which form at various densities, temperatures, and proton fractions. In this talk, we report on our calculations of lepton transport in nuclear pasta and the implication for neutron star observables.

  9. Are exotic herbivores better competitors? A meta-analysis.

    Science.gov (United States)

    Radville, Laura; Gonda-King, Liahna; Gómez, Sara; Kaplan, Ian; Preisser, Evan L

    2014-01-01

    Competition plays an important role in structuring the community dynamics of phytophagous insects. As the number and impact of biological invasions increase, it has become increasingly important to determine whether competitive differences exist between native and exotic insects. We conducted a meta-analysis to test the hypothesis that native/ exotic status affects the outcome of herbivore competition. Specifically, we used data from 160 published studies to assess plant-mediated competition in phytophagous insects. For each pair of competing herbivores, we determined the native range and coevolutionary history of each herbivore and host plant. Plant-mediated competition occurred frequently, but neither native nor exotic insects were consistently better competitors. Spatial separation reduced competition in native insects but showed little effect on exotics. Temporal separation negatively impacted native insects but did not affect competition in exotics. Insects that coevolved with their host plant were more affected by interspecific competition than herbivores that lacked a coevolutionary history. Insects that have not coevolved with their host plant may be at a competitive advantage if they overcome plant defenses. As native/exotic status does not consistently predict outcomes of competitive interactions, plant-insect coevolutionary history should be considered in studies of competition.

  10. Supernovae and nuclear structure: Electron capture and the nuclear incompressibility

    International Nuclear Information System (INIS)

    Cooperstein, J.

    1985-01-01

    The author considers the effects of electron capture and the high density equation of state on supernovae. Electron captures on nuclei with 60 s it is helpful for supernovae to have a soft equation of state. Present knowledge of the nuclear matter parameters is considered and implications for supernovae are drawn. (orig.)

  11. Design of concrete structures important to safety of nuclear facilities

    International Nuclear Information System (INIS)

    2001-10-01

    Civil engineering structures in nuclear installations form an important feature having implications to safety performance of these installations. The objective and minimum requirements for the design of civil engineering buildings/structures to be fulfilled to provide adequate assurance for safety of nuclear installations in India (such as pressurised heavy water reactor and related systems) are specified in the Safety standard for civil engineering structures important to safety of nuclear facilities. This standard is written by AERB to specify guidelines for implementation of the above civil engineering safety standard in the design of concrete structures important to safety

  12. New frontiers in nuclear structure studies

    International Nuclear Information System (INIS)

    Zwarts, D.; Walet, N.R.; Wolters, A.A.; Glaudemans, P.W.M.; VandeGraff, R.J.

    1985-01-01

    The need to go to larger model spaces for more detailed studies of the atomic nucleus has led to the introduction of the supercomputer to nuclear physics. In this report a brief survey of the nuclear shell model is presented and the performance of some of the relevant programs on different computer systems is compared

  13. Three-dimensional structure of low-density nuclear matter

    International Nuclear Information System (INIS)

    Okamoto, Minoru; Maruyama, Toshiki; Yabana, Kazuhiro; Tatsumi, Toshitaka

    2012-01-01

    We numerically explore the pasta structures and properties of low-density nuclear matter without any assumption on the geometry. We observe conventional pasta structures, while a mixture of the pasta structures appears as a metastable state at some transient densities. We also discuss the lattice structure of droplets.

  14. Three-dimensional structure of low-density nuclear matter

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Minoru, E-mail: okamoto@nucl.ph.tsukuba.ac.jp [Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Advanced Science Research Center, Japan Atomic Energy Agency, Shirakata Shirane 2-4, Tokai, Ibaraki 319-1195 (Japan); Maruyama, Toshiki, E-mail: maruyama.toshiki@jaea.go.jp [Advanced Science Research Center, Japan Atomic Energy Agency, Shirakata Shirane 2-4, Tokai, Ibaraki 319-1195 (Japan); Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Yabana, Kazuhiro, E-mail: yabana@nucl.ph.tsukuba.ac.jp [Graduate School of Pure and Applied Science, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Center of Computational Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8571 (Japan); Tatsumi, Toshitaka, E-mail: tatsumi@ruby.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2012-07-09

    We numerically explore the pasta structures and properties of low-density nuclear matter without any assumption on the geometry. We observe conventional pasta structures, while a mixture of the pasta structures appears as a metastable state at some transient densities. We also discuss the lattice structure of droplets.

  15. Integrative structure and functional anatomy of a nuclear pore complex

    Science.gov (United States)

    Kim, Seung Joong; Fernandez-Martinez, Javier; Nudelman, Ilona; Shi, Yi; Zhang, Wenzhu; Raveh, Barak; Herricks, Thurston; Slaughter, Brian D.; Hogan, Joanna A.; Upla, Paula; Chemmama, Ilan E.; Pellarin, Riccardo; Echeverria, Ignacia; Shivaraju, Manjunatha; Chaudhury, Azraa S.; Wang, Junjie; Williams, Rosemary; Unruh, Jay R.; Greenberg, Charles H.; Jacobs, Erica Y.; Yu, Zhiheng; de La Cruz, M. Jason; Mironska, Roxana; Stokes, David L.; Aitchison, John D.; Jarrold, Martin F.; Gerton, Jennifer L.; Ludtke, Steven J.; Akey, Christopher W.; Chait, Brian T.; Sali, Andrej; Rout, Michael P.

    2018-03-01

    Nuclear pore complexes play central roles as gatekeepers of RNA and protein transport between the cytoplasm and nucleoplasm. However, their large size and dynamic nature have impeded a full structural and functional elucidation. Here we determined the structure of the entire 552-protein nuclear pore complex of the yeast Saccharomyces cerevisiae at sub-nanometre precision by satisfying a wide range of data relating to the molecular arrangement of its constituents. The nuclear pore complex incorporates sturdy diagonal columns and connector cables attached to these columns, imbuing the structure with strength and flexibility. These cables also tie together all other elements of the nuclear pore complex, including membrane-interacting regions, outer rings and RNA-processing platforms. Inwardly directed anchors create a high density of transport factor-docking Phe-Gly repeats in the central channel, organized into distinct functional units. This integrative structure enables us to rationalize the architecture, transport mechanism and evolutionary origins of the nuclear pore complex.

  16. Integrative structure and functional anatomy of a nuclear pore complex.

    Science.gov (United States)

    Kim, Seung Joong; Fernandez-Martinez, Javier; Nudelman, Ilona; Shi, Yi; Zhang, Wenzhu; Raveh, Barak; Herricks, Thurston; Slaughter, Brian D; Hogan, Joanna A; Upla, Paula; Chemmama, Ilan E; Pellarin, Riccardo; Echeverria, Ignacia; Shivaraju, Manjunatha; Chaudhury, Azraa S; Wang, Junjie; Williams, Rosemary; Unruh, Jay R; Greenberg, Charles H; Jacobs, Erica Y; Yu, Zhiheng; de la Cruz, M Jason; Mironska, Roxana; Stokes, David L; Aitchison, John D; Jarrold, Martin F; Gerton, Jennifer L; Ludtke, Steven J; Akey, Christopher W; Chait, Brian T; Sali, Andrej; Rout, Michael P

    2018-03-22

    Nuclear pore complexes play central roles as gatekeepers of RNA and protein transport between the cytoplasm and nucleoplasm. However, their large size and dynamic nature have impeded a full structural and functional elucidation. Here we determined the structure of the entire 552-protein nuclear pore complex of the yeast Saccharomyces cerevisiae at sub-nanometre precision by satisfying a wide range of data relating to the molecular arrangement of its constituents. The nuclear pore complex incorporates sturdy diagonal columns and connector cables attached to these columns, imbuing the structure with strength and flexibility. These cables also tie together all other elements of the nuclear pore complex, including membrane-interacting regions, outer rings and RNA-processing platforms. Inwardly directed anchors create a high density of transport factor-docking Phe-Gly repeats in the central channel, organized into distinct functional units. This integrative structure enables us to rationalize the architecture, transport mechanism and evolutionary origins of the nuclear pore complex.

  17. Investigation of nuclear structures using transition probabilities

    International Nuclear Information System (INIS)

    Dewald, A.; Moeller, O.; Peusquens, R.

    2002-01-01

    Magnetic rotation which appears as regular M1 bands in the spectra, is a well established phenomenon in several Pb isotopes. In the A = 130 region where similar M1 bands are known, e.g. in 124 Xe and 128 Ba, it is still not clear whether it does exists. Crucial experimental observables are the B (M1) values which -are expected to decrease with in creasing spin. At Strasbourg a recoil distance measurement (RDM) with the EUROBALL spectrometer at Strasbourg and the Koeln plunger using the reaction 110 Pd( 18 O, 4n) 124 Xe at a beam energy of 86 MeV yielded preliminary lifetimes of ground band states and states of the M1 band. The deduced B(M1) values show the expected behaviour for magnetic rotation. It is also shown that the experimental B(M1) values can be described as well on the basis of a rotational band. The measured B(E2) values are used to investigate the nuclear deformation of 124 Xe as well as the interaction of the ground state band with two s-bands. Spherical deformed shape coexistence is investigated by means of electromagnetic transition probabilities in the case of 188 Pb. Lifetimes were measured in 188 Pb using a novel combination of the Koeln plunger device with the GSFMA set-up at ATLAS. The reaction 40 Ca ( 152 Sm, 4n) 188 Pb at a beam energy of 725 MeV in inverse kinematics is used. It is found that the lowest 2 + state is predominantly of prolate structure

  18. Proton capture reactions and nuclear structure

    International Nuclear Information System (INIS)

    Kikstra, S.W.

    1989-01-01

    Experimental studies are described of the structure of 40 Ca and 42 Sc with measurements at proton-capture of (p, gamma) reactions. Where possible, an attempt has been made to interpret the results of the measurements in termsof existing models. The 40 Ca and 42 Sc nuclides were excited by bombarding 39 K and 41 Ca targets, respectively with low energy protons (E p = 0.3-3.0 MeV), that were produced by the Utrecht 3MV van de Graaff accelerator. From the measured energy and intensity of the gamma-rays created in the subsequent decay of the cuclei, information was obtained on the existence and properties of their excited states. In addition properties of two T = 3/2 levels at high excitation energy of the 9 Be nucleus were investigated. These levels were excited by the resonant absorption of gamma-rays from the 11 B(p, gamma) 12 C reaction. The results of the measurements are interpreted by a comparison to the analoque β-decay of 9 Li and to shell model calculations. The total decay energy of the superallowed O + → O + transition between the ground states of 42 Sc and 42 Ca was determined by measurements in Utrecht of the proton separation energy S p of 42 Sc and in Oak Ridge of S n of 42 Sc and 42 Ca. The results were used for verification of the conserved vector current hypothesis, which implies that the ft values of all superallowed O + → O + β-decays are the same. An attempt was made to describe properties of odd-parity states of A = 37-41 nuclei with a variant of the Warburton, Becker, Millener and Brown (WBMB) interaction.Finally a new method for the assignment of nuclear spins by a simple statistical analysis of spectroscopic information is proposed. (author). 169 refs.; 22 figs.; 24 schemes; 29 tabs

  19. Exotic nuclei and astrophysics

    Directory of Open Access Journals (Sweden)

    Penionzhkevich Yu.

    2012-12-01

    Full Text Available In recent years, nuclear physics investigations of the laws of the microscopic world contributed significantly to extension of our knowledge of phenomena occurring in the macroscopic world (Universe and made a formidable contribution to the development of astrophysical and cosmological theories. First of all, this concerns the expanding universe model, the evolution of stars, and the abundances of elements, as well as the properties of various stars and cosmic objects, including “cold” and neutron stars, black holes, and pulsars. Without claiming to give a full account of all cosmological problems, we will dwell upon those of them that, in my opinion, have much in common with nuclear-matter properties manifesting themselves in nuclear interactions.

  20. Relativistic density functional for nuclear structure

    CERN Document Server

    2016-01-01

    This book aims to provide a detailed introduction to the state-of-the-art covariant density functional theory, which follows the Lorentz invariance from the very beginning and is able to describe nuclear many-body quantum systems microscopically and self-consistently. Covariant density functional theory was introduced in nuclear physics in the 1970s and has since been developed and used to describe the diversity of nuclear properties and phenomena with great success. In order to provide an advanced and updated textbook of covariant density functional theory for graduate students and nuclear physics researchers, this book summarizes the enormous amount of material that has accumulated in the field of covariant density functional theory over the last few decades as well as the latest developments in this area. Moreover, the book contains enough details for readers to follow the formalism and theoretical results, and provides exhaustive references to explore the research literature.

  1. The evaluated nuclear structure data file: Philosophy, content, and uses

    International Nuclear Information System (INIS)

    Burrows, T.W.

    1990-01-01

    The Evaulated Nuclear Structure Data File (ENSDF) is maintained by the National Nuclear Data Center (NNDC) on behalf of the international Nuclear Structure and Decay Data Network sponsored by the International Atomic Energy Agency, Vienna. Data for A=5 to 44 are extracted from the evaluations published in Nuclear Physics; for A≥45 the file is used to produce the Nuclear Data Sheets. The philosophy and methodology of ENSDF evaluations are outlined, along with the file contents of relevance to radionuclide metrologists; the service available at various nuclear data centers and the NNDC on-line capabilities are also discussed. Application codes have been developed for use with ENSDF, and the program RADLST is used as an example. The interaction of ENSDF evaluation with other evaluations is also discussed. (orig.)

  2. Fourteenth Exotic Beam Summer School EBSS 2015

    International Nuclear Information System (INIS)

    Wiedenhoever, Ingo

    2016-01-01

    The Fourteenth Annual Exotic Beam Summer School EBSS 2015 was held August 2nd - August 7th, 2015, and belongs to the series of summer programs aimed at educating future workforce in nuclear physics-related areas, mostly about the challenges of radioactive ion beam physics. Through these schools the research community will be able to exploit fully the opportunities created by the exotic beam facilities. These facilities in the US include CARIBU at ANL, the NSCL and the future FRIB laboratory as well as smaller-scale university laboratories. The skill set needed by the future workforce is very diverse and a fundamental understanding of theoretical, technical, computational and applied fields are all important. Therefore, the Exotic Beam Summer Schools follow a unique approach, in which the students not only receive lectures but also participate in hands-on activities. The lectures covered broad topics in both the experimental and theoretical physics of nuclei far from stability as well as radioactive ions production and applications. The afternoons provided opportunities for 'hands-on' projects with experimental equipment and techniques useful in FRIB research. Five activities were performed in groups of eight students, rotating through the activities over the five afternoons of the school. The center of the activities was an experiment at the FSU tandem accelerator, measuring the angular distribution and cross section of the "1"2C(d,p)"1"3C transfer reaction, measured with a silicon telescope in a scattering chamber. The experimental data were analyzed by performing a DWBA calculation with the program DWUCK, and the resulting spectroscopic factors were compared to a shell model calculation. The other activities included target preparation, digital gamma-spectroscopy and modern neutron detection methods.

  3. Fourteenth Exotic Beam Summer School EBSS 2015

    Energy Technology Data Exchange (ETDEWEB)

    Wiedenhoever, Ingo [Florida State Univ., Tallahassee, FL (United States). Dept. of Physics

    2016-07-11

    The Fourteenth Annual Exotic Beam Summer School EBSS 2015 was held August 2nd - August 7th, 2015, and belongs to the series of summer programs aimed at educating future workforce in nuclear physics-related areas, mostly about the challenges of radioactive ion beam physics. Through these schools the research community will be able to exploit fully the opportunities created by the exotic beam facilities. These facilities in the US include CARIBU at ANL, the NSCL and the future FRIB laboratory as well as smaller-scale university laboratories. The skill set needed by the future workforce is very diverse and a fundamental understanding of theoretical, technical, computational and applied fields are all important. Therefore, the Exotic Beam Summer Schools follow a unique approach, in which the students not only receive lectures but also participate in hands-on activities. The lectures covered broad topics in both the experimental and theoretical physics of nuclei far from stability as well as radioactive ions production and applications. The afternoons provided opportunities for "hands-on" projects with experimental equipment and techniques useful in FRIB research. Five activities were performed in groups of eight students, rotating through the activities over the five afternoons of the school. The center of the activities was an experiment at the FSU tandem accelerator, measuring the angular distribution and cross section of the 12C(d,p)13C transfer reaction, measured with a silicon telescope in a scattering chamber. The experimental data were analyzed by performing a DWBA calculation with the program DWUCK, and the resulting spectroscopic factors were compared to a shell model calculation. The other activities included target preparation, digital gamma-spectroscopy and modern neutron detection methods.

  4. Nuclear physics at the KAON factory

    International Nuclear Information System (INIS)

    Kitching, R.

    1989-05-01

    The author surveys the range of nuclear physics issues which can be addressed with a high intensity hadron facility such as the KAON factory. He discusses hadron spectroscopy, kaon scattering, hypernuclear physics, spin physics, and nuclear physics with neutrinos. Nuclear Physics is defined rather broadly, encompassing the study of strongly interacting systems, and including the structure of individual hadrons, hadron-hadron interactions, hadronic weak and electromagnetic currents (in nuclei too), conventional nuclear structure, and exotic nuclei. The basic theme is how the KAON Factory can shed light on non-perturbative QCD and its relation to conventional nuclear physics

  5. Aging management of containment structures in nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.; Graves, H.L. III; Norris, W.E.

    1994-01-01

    Research is being conducted by ORNL under US Nuclear Regulatory Commission (USNRC) sponsorship to address aging management of nuclear power plant containment and other safety-related structures. Documentation is being prepared to provide the USNRC with potential structural safety issues and acceptance criteria for use in continued service evaluations of nuclear power plants. Accomplishments include development of a Structural Materials Information Center containing data and information on the time variation of 144 material properties under the influence of pertinent environmental stressors or aging factors, evaluation of models for potential concrete containment degradation factors, development of a procedure to identify critical structures and degradation factors important to aging management, evaluations of nondestructive evaluation techniques. assessments of European and North American repair practices for concrete, review of parameters affecting corrosion of metals embedded in concrete, and development of methodologies for making current condition assessments and service life predictions of new or existing reinforced concrete structures in nuclear power plants

  6. Exotic nuclei: Halos

    Energy Technology Data Exchange (ETDEWEB)

    Orr, Nigel [Lab. de Physique Corpusculaire, Caen Univ., 14 (France); Collaboration: La Direction des Sciences de la Matiere du CEA (FR); Le Fonds National de la Recherche Scientifique de Belgique (BE)

    1998-12-31

    A brief overview of the nuclear halo is presented. Following some historical remarks the general characteristics of the halo systems are discussed with reference to a simple model. The conditions governing the formation of halos are also explored, as are two subjects of current interest - low-lying resonances of halo nucleon correlations. (author) 54 refs., 16 figs., 1 tabs.

  7. A New Light Weight Structural Material for Nuclear Structures

    International Nuclear Information System (INIS)

    Rabiei, Afsaneh

    2016-01-01

    Radiation shielding materials are commonly used in nuclear facilities to attenuate the background ionization radiations to a minimum level for creating a safer workplace, meeting regulatory requirements and maintaining high quality performance. The conventional radiation shielding materials have a number of drawbacks: heavy concrete contains a high amount of elements that are not desirable for an effective shielding such as oxygen, silicon, and calcium; a well known limitation of lead is its low machinability and toxicity, which is causing a major environmental concern. Therefore, an effective and environmentally friendly shielding material with increased attenuation and low mass density is desirable. Close-cell composite metal foams (CMFs) and open-cell Al foam with fillers are light-weight candidate materials that we have studied in this project. Close-cell CMFs possess several suitable properties that are unattainable by conventional radiation shielding materials such as low density and high strength for structural applications, high surface area to volume ratio for excellent thermal isolation with an extraordinary energy absorption capability. Open-cell foam is made up of a network of interconnected solid struts, which allows gas or fluid media to pass through it. This unique structure provided a further motive to investigate its application as radiation shields by infiltrating original empty pores with high hydrogen or boron compounds, which are well known for their excellent neutron shielding capability. The resulting open-cell foam with fillers will not only exhibit light weight and high specific surface area, but also possess excellent radiation shielding capability and good processability. In this study, all the foams were investigated for their radiation shielding efficiency in terms of X-ray, gamma ray and neutron. X-ray transmission measurements were carried out on a high-resolution microcomputed tomography (microCT) system. Gamma-emitting sources: 3.0m

  8. A New Light Weight Structural Material for Nuclear Structures

    Energy Technology Data Exchange (ETDEWEB)

    Rabiei, Afsaneh [North Carolina State Univ., Raleigh, NC (United States)

    2016-01-14

    Radiation shielding materials are commonly used in nuclear facilities to attenuate the background ionization radiations to a minimum level for creating a safer workplace, meeting regulatory requirements and maintaining high quality performance. The conventional radiation shielding materials have a number of drawbacks: heavy concrete contains a high amount of elements that are not desirable for an effective shielding such as oxygen, silicon, and calcium; a well known limitation of lead is its low machinability and toxicity, which is causing a major environmental concern. Therefore, an effective and environmentally friendly shielding material with increased attenuation and low mass density is desirable. Close-cell composite metal foams (CMFs) and open-cell Al foam with fillers are light-weight candidate materials that we have studied in this project. Close-cell CMFs possess several suitable properties that are unattainable by conventional radiation shielding materials such as low density and high strength for structural applications, high surface area to volume ratio for excellent thermal isolation with an extraordinary energy absorption capability. Open-cell foam is made up of a network of interconnected solid struts, which allows gas or fluid media to pass through it. This unique structure provided a further motive to investigate its application as radiation shields by infiltrating original empty pores with high hydrogen or boron compounds, which are well known for their excellent neutron shielding capability. The resulting open-cell foam with fillers will not only exhibit light weight and high specific surface area, but also possess excellent radiation shielding capability and good processability. In this study, all the foams were investigated for their radiation shielding efficiency in terms of X-ray, gamma ray and neutron. X-ray transmission measurements were carried out on a high-resolution microcomputed tomography (microCT) system. Gamma-emitting sources: 3.0m

  9. Procedures manual for the Evaluated Nuclear Structure Data File

    International Nuclear Information System (INIS)

    Bhat, M.R.

    1987-10-01

    This manual is a collection of various notes, memoranda and instructions on procedures for the evaluation of data in the Evaluated Nuclear Structure Data File (ENSDF). They were distributed at different times over the past few years to the evaluators of nuclear structure data and some of them were not readily avaialble. Hence, they have been collected in this manual for ease of reference by the evaluators of the international Nuclear Structure and Decay Data (NSDD) network contribute mass-chains to the ENSDF. Some new articles were written specifically for this manual and others are reivsions of earlier versions

  10. Compilations and evaluations of nuclear structure and decay data

    International Nuclear Information System (INIS)

    Lorenz, A.

    1977-10-01

    This is the third issue of a report series on published and to-be-published compilations and evaluations of nuclear structure and decay (NSD) data. This compilation is published and distributed by the IAEA Nuclear Data Section approximately every six months. This compilation of compilations and evaluations is designed to keep the nuclear scientific community informed of the availability of compiled or evaluated NSD data, and contains references to laboratory reports, journal articles and books containing selected compilations and evaluations

  11. Changes in attitude structure toward nuclear power in the nuclear power plant locations of Tohoku district

    International Nuclear Information System (INIS)

    Tsujikawa, Norifumi; Tsuchida, Shoji; Shiotani, Takamasa; Nakagawa, Yuri

    2012-01-01

    This survey was examined the changes in structure of attitude toward nuclear power and the influence of environmental value on the attitude structure before and after the accident at the Fukushima No. 1 nuclear power plant. With residents of Aomori, Miyagi, and Fukushima prefectures as participants, we conducted online surveys in November 2009 and October 2011. Comparing the results before and after the accident, we found that trust in the management of nuclear power plants had a stronger influence on the perceived risk and benefit regarding nuclear power after the accident than before the accident. The value of concern about environmental destruction resulted in reduced trust in the management. (author)

  12. Forging the link between nuclear reactions and nuclear structure.

    Science.gov (United States)

    Mahzoon, M H; Charity, R J; Dickhoff, W H; Dussan, H; Waldecker, S J

    2014-04-25

    A comprehensive description of all single-particle properties associated with the nucleus Ca40 is generated by employing a nonlocal dispersive optical potential capable of simultaneously reproducing all relevant data above and below the Fermi energy. The introduction of nonlocality in the absorptive potentials yields equivalent elastic differential cross sections as compared to local versions but changes the absorption profile as a function of angular momentum suggesting important consequences for the analysis of nuclear reactions. Below the Fermi energy, nonlocality is essential to allow for an accurate representation of particle number and the nuclear charge density. Spectral properties implied by (e, e'p) and (p, 2p) reactions are correctly incorporated, including the energy distribution of about 10% high-momentum nucleons, as experimentally determined by data from Jefferson Lab. These high-momentum nucleons provide a substantial contribution to the energy of the ground state, indicating a residual attractive contribution from higher-body interactions for Ca40 of about 0.64  MeV/A.

  13. Core-satellite species hypothesis and native versus exotic species in secondary succession

    Science.gov (United States)

    Martinez, Kelsey A.; Gibson, David J.; Middleton, Beth A.

    2015-01-01

    A number of hypotheses exist to explain species’ distributions in a landscape, but these hypotheses are not frequently utilized to explain the differences in native and exotic species distributions. The core-satellite species (CSS) hypothesis predicts species occupancy will be bimodally distributed, i.e., many species will be common and many species will be rare, but does not explicitly consider exotic species distributions. The parallel dynamics (PD) hypothesis predicts that regional occurrence patterns of exotic species will be similar to native species. Together, the CSS and PD hypotheses may increase our understanding of exotic species’ distribution relative to natives. We selected an old field undergoing secondary succession to study the CSS and PD hypotheses in conjunction with each other. The ratio of exotic to native species (richness and abundance) was observed through 17 years of secondary succession. We predicted species would be bimodally distributed and that exotic:native species ratios would remain steady or decrease through time under frequent disturbance. In contrast to the CSS and PD hypotheses, native species occupancies were not bimodally distributed at the site, but exotic species were. The exotic:native species ratios for both richness (E:Nrichness) and abundance (E:Ncover) generally decreased or remained constant throughout supporting the PD hypothesis. Our results suggest exotic species exhibit metapopulation structure in old field landscapes, but that metapopulation structures of native species are disrupted, perhaps because these species are dispersal limited in the fragmented landscape.

  14. Particle production from nuclear targets and the structure of hadrons

    International Nuclear Information System (INIS)

    Bialas, A.

    Production processes from nuclear targets allow studying interactions of elementary hadronic constituents in nuclear matter. The information thus obtained on the structure of hadrons and on the properties of hadronic constituents is presented. Both soft (low momentum transfer) and hard (high momentum transfer) processes are discussed. (author)

  15. A workshop report on nuclear reaction and cluster structure

    International Nuclear Information System (INIS)

    1985-01-01

    A work shop was held in June 1984 at RCNP (Research Center for Nuclear Physics), Osaka University, to discuss theory of nuclear reactions based on studies from microscopic or cluster structure viewpoints. About forty researchers participated in this work shop and 27 paperes were presented. All these papers with English abstracts are gathered in this collective report. (Aoki, K.)

  16. High spin exotic states and new method for pairing energy

    International Nuclear Information System (INIS)

    Molique, H.

    1996-01-01

    We present a new method called 'PSY-MB', initially developed in the framework of abstract group theory for the solution of the problem of strongly interacting multi-fermionic systems with particular to systems in an external rotating field. The validity of the new method (PSY-MB) is tested on model Hamiltonians. A detailed comparison between the obtained solutions and the exact ones is performed. The new method is used in the study of realistic nuclear Hamiltonians based on the Woods-Saxon potential within the cranking approximation to study the influence of residual monopole pairing interactions in the rare-earth mass region. In parallel with this new technique we present original results obtained with the Woods-Saxon mean-field and the self-consistent Hartree-Fock approximation in order to investigate such exotic effects as octupole deformations and hexadecapole C 4 -polarizing deformations in the framework of high-spin physics. By developing these three approaches in one single work we prepare the ground for the nuclear structure calculations of the new generation - where the residual two-body interactions are taken into account also in the weak pairing limit. (author)

  17. Isotopically enriched structural materials in nuclear devices

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, L.W.G., E-mail: Lee.Morgan@ccfe.ac.uk [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Shimwell, J. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Gilbert, M.R. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

    2015-01-15

    Highlights: • C-B analysis of isotopic enrichment of structural materials is presented. • Some, previously, prohibited elements could be used as alloying elements in LAM's. • Adding enriched molybdenum and nickel, to EUROFER, could increase availability. • Isotope enrichment for EUROFER could be cost-effective. • Isotopically enriching copper, in CuCrZr, can reduce helium production by 50%. - Abstract: A large number of materials exist which have been labeled as low activation structural materials (LAM). Most often, these materials have been designed in order to substitute-out or completely remove elements that become activated and contribute significantly to shut-down activity after being irradiated by neutrons in a reactor environment. To date, one of the fundamental principles from which LAMs have been developed is that natural elemental compositions are the building blocks of LAMs. Thus, elements such as Co, Al, Ni, Mo, Nb, N and Cu that produce long-lived decay products are significantly reduced or removed from the LAM composition. These elements have an important part to play in the composition of steels and the removal/substitution can have a negative impact on materials properties such as yield stress and fracture toughness. This paper looks in more detail at whether using isotopic selection of the more mechanically desirable, but prohibited due to activation, elements can improve matters. In particular, this paper focuses on the activation of Eurofer. Carefully chosen isotopically enriched elements, which are normally considered to be on the prohibited element list, are added to EUROFER steel as potential alloying elements. The EUROFER activation results show that some prohibited elements can be used as alloying elements in LAM steels, providing the selected isotopes do not have a significant impact on waste disposal rating or shut-down dose. The economic implications of isotopically enriching elements and the potential implications for

  18. Electronic structure of fractionally nuclear charged atoms

    International Nuclear Information System (INIS)

    Pavao, Antonio C.; Bastos, Cristiano C.; Ferreira, Joacy V.

    2008-01-01

    Different properties of quark chemistry are studied by performing accurate ab initio Hartree- Fock calculations on fractionally nuclear charged atoms. Ground and first excited states of sodium atoms with quarks attached to the nucleus are obtained using CI calculations. It is suggested that the sodium 2 P -> 2 S electronic transition can be used as a guide in searching for unconfined quarks. Also, the variation of the binding electronic energy with nuclear charge in the isoelectronic series of fractionally nuclear charged atoms A ±2/3 and A ±1/3 (A = H, Li, Na, P and Ca) is analyzed. The present calculations suggest that unconfined colored particles have large appetite for heavy nuclei and that quark-antiquark pairs could be stabilized in presence of the atomic matter. (author)

  19. Experimental test of nuclear magnetization distribution and nuclear structure models

    International Nuclear Information System (INIS)

    Beirsdorfer, P; Crespo-Lopez-Urrutia, J R; Utter, S B.

    1999-01-01

    Models exist that ascribe the nuclear magnetic fields to the presence of a single nucleon whose spin is not neutralized by pairing it up with that of another nucleon; other models assume that the generation of the magnetic field is shared among some or all nucleons throughout the nucleus. All models predict the same magnetic field external to the nucleus since this is an anchor provided by experiments. The models differ, however, in their predictions of the magnetic field arrangement within the nucleus for which no data exist. The only way to distinguish which model gives the correct description of the nucleus would be to use a probe inserted into the nucleus. The goal of our project was to develop exactly such a probe and to use it to measure fundamental nuclear quantities that have eluded experimental scrutiny. The need for accurately knowing such quantities extends far beyond nuclear physics and has ramifications in parity violation experiments on atomic traps and the testing of the standard model in elementary particle physics. Unlike scattering experiments that employ streams of free particles, our technique to probe the internal magnetic field distribution of the nucleus rests on using a single bound electron. Quantum mechanics shows that an electron in the innermost orbital surrounding the nucleus constantly dives into the nucleus and thus samples the fields that exist inside. This sampling of the nucleus usually results in only minute shifts in the electron s average orbital, which would be difficult to detect. By studying two particular energy states of the electron, we can, however, dramatically enhance the effects of the distribution of the magnetic fields in the nucleus. In fact about 2% of the energy difference between the two states, dubbed the hyperfine splitting, is determined by the effects related to the distribution of magnetic fields in the nucleus, A precise measurement of this energy difference (better than 0.01%) would then allow us to place

  20. Nuclear structure research at the Triangle Universities Nuclear Laboratory

    International Nuclear Information System (INIS)

    Mitchell, G.E.

    1992-01-01

    Studies of fundamental symmetries by the TRIPLE collaboration using the unique capabilities at LAMTF have found unexpected systematics in the parity-violating amplitudes for epithermal-neutron scattering. Tests to lower the present limits on time-reversal-invariance violation in the strong interaction are being made at in experiments on the scattering of polarized fast neutrons from aligned holmium targets. Studies of few-nucleon systems have received increasing emphasis over the past year, involving a broad program for testing the low- to medium-energy internucleon interactions, from the tensor component in n-p scattering and the n-n scattering lengths, through three-nucleon systems and the alpha particle, on up to 8 Be. Of particular interest are three-nucleon systems, both in elastic scattering and in three-body breakup. Beam requirements range from production of intense and highly-polarized neutron beams to tensor-polarized beams for measurements at both very low energies (25--80 keV) and at tandem energies for definitive measurements of D-state components of the triton, 3 He, and 4 He obtained from transfer reactions. The program in nuclear astrophysics expanded during 1991--1992. Several facets of the nuclear many-body problem and of excitation mechanisms of the nucleus are being elucidated, including measurements and analyses to elucidate the neutron--nucleus elastic-scattering interaction over a wide range of nuclei and energies. Several projects involved developments in electronuclear physics, instrumentation, rf-transition units, and low-temperature bolometric particle detectors

  1. Nuclear reactor fuel assemblies and end fitting grid structures therefor

    International Nuclear Information System (INIS)

    Jabsen, F.S.

    1978-01-01

    An improved end fitting grid structure is described for nuclear fuel assemblies which overcomes the need for load-bearing control rod guide tubes and the expensive special fittings that these tubes required. (UK)

  2. Nuclear structure notes on element 115 decay chains

    International Nuclear Information System (INIS)

    Rudolph, D.; Sarmiento, L. G.; Forsberg, U.

    2015-01-01

    Hitherto collected data on more than hundred α-decay chains stemming from element 115 are combined to probe some aspects of the underlying nuclear structure of the heaviest atomic nuclei yet created in the laboratory

  3. Nuclear structure notes on element 115 decay chains

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, D., E-mail: Dirk.Rudolph@nuclear.lu.se; Sarmiento, L. G.; Forsberg, U. [Department of Physics, Lund University, 22100 Lund (Sweden)

    2015-10-15

    Hitherto collected data on more than hundred α-decay chains stemming from element 115 are combined to probe some aspects of the underlying nuclear structure of the heaviest atomic nuclei yet created in the laboratory.

  4. Phase relations, crystal structures and physical properties of nuclear fuels

    International Nuclear Information System (INIS)

    Tagawa, Hiroaki; Fujino, Takeo; Tateno, Jun

    1975-07-01

    Phase relations, crystal structures and physical properties of the compounds for nuclear fuels are presented, including melting point, thermal expansion, diffusion and magnetic and electric properties. Emphasis is on oxides, carbides and nitrides of thorium, uranium and plutonium. (auth.)

  5. Impact of the structural changes on the nuclear safety

    International Nuclear Information System (INIS)

    Ziakova, M.

    2005-01-01

    In this presentation author deals with impact of the structural changes (privatization of the Slovenske Elektrarne, a.s.) and new Atomic law (541/2004 Coll. Laws) on the nuclear safety in the Slovak Republic.

  6. Construction of special structures for nuclear power projects

    International Nuclear Information System (INIS)

    Raghavan, N.

    2003-01-01

    Construction is a very important stage in the course of realization of Nuclear Power Projects and as much care has be devoted to this stage as to the planning and engineering stages. While the setting up of nuclear power projects used to take over seven years in the past, the time period has now been considerably reduced to about five years with advancements in construction engineering, project management and design techniques, on the basis of new initiatives from the owner agency, Nuclear Power Corporation of India. In this article, the constructional aspects of the specialized structures for nuclear power generation are looked into. (author)

  7. Hierarchical structure for risk criteria applicable to nuclear power plants

    International Nuclear Information System (INIS)

    Hall, R.E.; Mitra, S.P.

    1985-01-01

    This paper discusses the development of a hierarchical structure for risk criteria applicable to nuclear power plants. The structure provides a unified framework to systematically analyze the implications of different types of criteria, each focusing on a particular aspect of nuclear power plant risks. The framework allows investigation of the specific coverage of a particular criterion and comparison of different criteria with regard to areas to which they apply. 5 refs., 2 figs

  8. Aircraft impact on nuclear power plants concrete structures

    International Nuclear Information System (INIS)

    Coombs, R.F.; Barbosa, L.C.B.; Santos, S.H.C.

    1980-01-01

    A summary about the procedures for the analysis of aircraft on concrete structures, aiming to emphasize the aspects related to the nuclear power plants safety, is presented. The impact force is determined by the Riera model. The effect of this impact force on the concrete structures is presented, showing the advantages to use nonlinear behaviour in the concrete submitted to short loads. The simplifications used are shown through a verification example of the nuclear reactor concrete shielding. (E.G.) [pt

  9. The structure of the nuclear industry

    International Nuclear Information System (INIS)

    Leaist, G.T.; Morisette, E.F.

    1981-01-01

    Since 1952, when Canadians began to study the application of reactors to power generation, the CANDU reactor design and the manufacturing and and engineering capability supporting it have evolved into a world-class technology. At present, Atomic Energy of Canada Ltd. works directly with provincial electrical utilities in developing their power reactor requirements. It assumes responsibility for the detailed design of the nuclear steam supply system of stations, undertakes some procurement activities, and may represent the utilities in licensing applications. The detailed design and supply of components for the remainder of the nuclear steam plant, as well as for the secondary plant, are provided in Ontario by Ontario Hydro together with manufacturers, and in Quebec and New Brunswick by private firms. Canadian utilities have always assumed the project managment function themselves, but with export sales AECL has taken turnkey responsiblity for either the nuclear steam plant or the complete power station. AECL owns design specifications and other documentation, the use of which it can license, but manufacturing technology resides with Canadian industry. Canadian manufacturers have supported AECL design licensing initiatives overseas. The Canadian nuclear industry's major problem is the current lack of a vigorous domestic market combined with an uncertain international one

  10. Nuclear structure and double beta decay

    International Nuclear Information System (INIS)

    Vogel, P.

    1988-01-01

    Double beta decay is a rare transition between two nuclei of the same mass number A involving a change of the nuclear charge Z by two units. It has long been recognized that the Oν mode of double beta decay, where two electrons and no neutrinos are emitted, is a powerful tool for the study of neutrino properties. Its observation would constitute a convincing proof that there exists a massive Majorana neutrino which couples to electrons. Double beta decay is a process involving an intricate mixture of particle physics and physics of the nucleus. The principal nuclear physics issues have to do with the evaluation of the nuclear matrix elements responsible for the decay. If the authors wish to arrive at quantitative answers for the neutrino properties the authors have no choice but to learn first how to understand the nuclear mechanisms. The authors describe first the calculation of the decay rate of the 2ν mode of double beta decay, in which two electrons and two antineutrinos are emitted

  11. Nuclear Structures Surrounding Internal Lamin Invaginations

    Czech Academy of Sciences Publication Activity Database

    Legartová, Soňa; Stixová, Lenka; Laur, O.; Kozubek, Stanislav; Sehnalová, Petra; Bártová, Eva

    2014-01-01

    Roč. 115, č. 3 (2014), s. 476-487 ISSN 0730-2312 R&D Projects: GA MŠk(CZ) LD11020 Institutional support: RVO:68081707 Keywords : LAMINS * NUCLEAR PORES * CHROMATIN Subject RIV: BO - Biophysics Impact factor: 3.263, year: 2014

  12. Multiquark exotics (baryonium, dibaryons etc)

    International Nuclear Information System (INIS)

    Kondratyuk, L.A.

    1987-01-01

    The multiquark exotic resonant states q 2 -(anti q) 2 , q 3 -(anti q) 3 , q 6 and q 9 are discussed as systems composed of the few colour clusters. Special attention is devoted to the problem of narrow resonances in channels anti NN, Δanti p+pions, πNN and NN. 42 refs.; 2 figs.; 5 tabs

  13. Exotic meson studies at LHCb

    Directory of Open Access Journals (Sweden)

    Kreps Michal

    2014-01-01

    Full Text Available The latest years have seen a resurrection of interest in searches for exotic states motivated by tantalising observations of several states. Using the pp collisions data collected at 7 and 8 TeV by the LHCb experiment, we performed studies of the X(3872 decay rate to ψ (2Sγ final state, as well as confirmation the Z(4430+ state.

  14. Exotic decay in cerium isotopes

    Indian Academy of Sciences (India)

    Geiger–Nuttall plots were studied for different clusters and are found to be linear. Inclusion of proximity potential will not produce much deviation to linear nature of Geiger–Nuttall plots. It is observed that neutron excess in the parent nuclei slow down the exotic decay process. These findings support the earlier observations ...

  15. Constraints on Exotic Spin-Dependent Interactions Between Matter and Antimatter from Antiprotonic Helium Spectroscopy

    Science.gov (United States)

    Ficek, Filip; Fadeev, Pavel; Flambaum, Victor V.; Jackson Kimball, Derek F.; Kozlov, Mikhail G.; Stadnik, Yevgeny V.; Budker, Dmitry

    2018-05-01

    Heretofore undiscovered spin-0 or spin-1 bosons can mediate exotic spin-dependent interactions between standard model particles. Here, we carry out the first search for semileptonic spin-dependent interactions between matter and antimatter. We compare theoretical calculations and spectroscopic measurements of the hyperfine structure of antiprotonic helium to constrain exotic spin- and velocity-dependent interactions between electrons and antiprotons.

  16. Report on aging of nuclear power plant reinforced concrete structures

    International Nuclear Information System (INIS)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.

    1996-03-01

    The Structural Aging Program provides the US Nuclear Regulatory Commission with potential structural safety issues and acceptance criteria for use in continued service assessments of nuclear power plant safety-related concrete structures. The program was organized under four task areas: Program Management, Materials Property Data Base, Structural Component Assessment/Repair Technology, and Quantitative Methodology for Continued Service Determinations. Under these tasks, over 90 papers and reports were prepared addressing pertinent aspects associated with aging management of nuclear power plant reinforced concrete structures. Contained in this report is a summary of program results in the form of information related to longevity of nuclear power plant reinforced concrete structures, a Structural Materials Information Center presenting data and information on the time variation of concrete materials under the influence of environmental stressors and aging factors, in-service inspection and condition assessments techniques, repair materials and methods, evaluation of nuclear power plant reinforced concrete structures, and a reliability-based methodology for current and future condition assessments. Recommendations for future activities are also provided. 308 refs., 61 figs., 50 tabs

  17. Report on aging of nuclear power plant reinforced concrete structures

    Energy Technology Data Exchange (ETDEWEB)

    Naus, D.J.; Oland, C.B. [Oak Ridge National Lab., TN (United States); Ellingwood, B.R. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

    1996-03-01

    The Structural Aging Program provides the US Nuclear Regulatory Commission with potential structural safety issues and acceptance criteria for use in continued service assessments of nuclear power plant safety-related concrete structures. The program was organized under four task areas: Program Management, Materials Property Data Base, Structural Component Assessment/Repair Technology, and Quantitative Methodology for Continued Service Determinations. Under these tasks, over 90 papers and reports were prepared addressing pertinent aspects associated with aging management of nuclear power plant reinforced concrete structures. Contained in this report is a summary of program results in the form of information related to longevity of nuclear power plant reinforced concrete structures, a Structural Materials Information Center presenting data and information on the time variation of concrete materials under the influence of environmental stressors and aging factors, in-service inspection and condition assessments techniques, repair materials and methods, evaluation of nuclear power plant reinforced concrete structures, and a reliability-based methodology for current and future condition assessments. Recommendations for future activities are also provided. 308 refs., 61 figs., 50 tabs.

  18. Report of seminar on relativistic approach to nuclear reaction and nuclear structure

    International Nuclear Information System (INIS)

    1986-05-01

    A seminar on 'Relativistic Approach to Nuclear Reaction and Nuclear Structure' was held in 1985 at Osaka University. This booklet includes twenty-four reports given at the seminar, which deal with: Conventional Nonrelativistic Description of Nuclear Matter and Nuclear Spin-Orbit Interactions; Relativistic Approach to Nuclear Structure; Atomic and Molecular Structure Calculations; Electromagnetic Interaction in Nucleus and Relativistic Effect; Nuclear Magnetic Moment in the Relativistic Mean Field Theory, Effective Mass and Particle-Vibration Coupling in the Relativistic σ-ω Model; Gauge Invariance in Relativistic Many-Body Theory; Relativistic Description of Nucleon-Nucleon Interaction in Review; σ-Particle in NN Interaction; Nuclear Optical Potentials Based on the Brueckner-Hartree-Fock Approach; Elastic Backscattering and Optical Potential; Description of Intermediate-Energy Nuclear Reactions; Dirac Phenomenology at E(p) = 65 MeV; Relativistic Impulse Approximation; Reaction Studies with Intermediate Energy Deuterons at SATURNE; Folding Model for Intermediate-Energy Deutron Scattering; Folding Model for Polarized Deutron Scattering at 700 MeV; Dirac Approach Problems and a Different Viewpoint; Relativistic Approach and EMC Effect; Quasielastic Electron Scattering; Response Function of Quasielastic Electron Scattering; Relativistic Hartree Response Function for Quasielastic Electron Scattering on 12 C and 40 Ca; Backflow-, Retardation- and Relativistic Effects on the Longitudinal Response Function of Nuclear Matter; Pion-Photoproduction in the σ-ω Model. (Nogami, K.)

  19. Ageing evaluation model of nuclear reactors structural elements

    International Nuclear Information System (INIS)

    Ziliukas, A.; Jutas, A.; Leisis, V.

    2002-01-01

    In this article the estimation of non-failure probability by random faults on the structural elements of nuclear reactors is presented. Ageing is certainly a significant factor in determining the limits of nuclear plant lifetime or life extensions. Usually the non failure probability rates failure intensity, which is characteristic for structural elements ageing in nuclear reactors. In practice the reliability is increased incorrectly because not all failures are fixed and cumulated. Therefore, the methodology with using the fine parameter of the failures flow is described. The comparison of non failure probability and failures flow is carried out. The calculation of these parameters in the practical example is shown too. (author)

  20. Overturning behaviour of nuclear power plant structures during earthquakes

    International Nuclear Information System (INIS)

    Dalal, J.S.; Perumalswami, P.R.

    1977-01-01

    Nuclear power plant structures are designed to withstand severe postulated seismic forces. Structures subjected to such forces may be found to ''overturn'', if the factor of safety is computed in the traditional way, treating these forces as static. This study considers the transient nature of the problem and draws distinction between rocking, tipping and overturning. Responses of typical nuclear power plant structures to earthquake motions are used to assess their overturning potential more realistically. Structures founded on both rock and soil are considered. It is demonstrated that the traditional factor of safety, when smaller than unity, indicates only minimal base rotations and not necessarily overturning. (auth.)

  1. Nuclear structure investigations on spherical nuclei

    International Nuclear Information System (INIS)

    Heisenberg, J.; Calarco, J.; Dawson, J.; Hersman, F.W.

    1989-09-01

    This report discusses the following topics: electron scattering studies on spherical nuclei; electron scattering from collective states in deformed nuclei; proton and pion scattering studies; 12 C(e,e'p) and 16 O(e,e'p); 12 C(e,e'α) and 16 O(e,e'α); studies at high q at Bates; measurements with rvec e at Bates; 12 C(γ,p); future directions in giant resonance studies; proton knockout from 16 O; quasielastic studies at Bates; triple coincidence studies of nuclear correlations; contributions to (e,e'2p) at KIKHEF; contributions to instrumentation at CEBAF; instrumentation development at UNH; the Bates large acceptance spectrometer toroid; shell model and core polarization calculations; and the relativistic nuclear model

  2. The nuclear structure and low-energy reactions (NSLER) collaboration

    International Nuclear Information System (INIS)

    Dean, D J

    2006-01-01

    The long-term vision of the Nuclear Structure and Low-Energy Reactions (NSLER) collaboration is to arrive at a comprehensive and unified description of nuclei and their reactions that is grounded in the interactions between the constituent nucleons. For this purpose, we will develop a universal energy density functional for nuclei and replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that will deliver maximum predictive power with minimal uncertainties that are well quantified. Nuclear structure and reactions play an essential role in the science to be investigated at rare isotope facilities, and in nuclear physics applications to the Science-Based Stockpile Stewardship Program, next-generation reactors, and threat reduction. We anticipate an expansion of the computational techniques and methods we currently employ, and developments of new treatments, to take advantage of petascale architectures and demonstrate the capability of the leadership class machines to deliver new science heretofore impossible

  3. Quantum field theory and nuclear structure

    International Nuclear Information System (INIS)

    Celenza, L.S.; Goulard, B.; Shakin, C.M.

    1981-01-01

    We discuss recent successful calculations of the properties of nuclear matter within the context of theories exhibiting mass generation through spontaneous symmetry breaking. We start with the sigma model of Gell-Mann and Levy and introduce the nucleon mass (in a vacuum) in the usual manner. We relate the expectation value of the sigma field in a vacuum to a finite value of the scalar density. If the vacuum is now filled with nucleons (nuclear matter) the scalar density is increased and the new value for the nucleon mass must be determined. We exhibit the equation whose solution determines the new mass, and we also define a perturbative scheme for the determination of this mass. This scheme involves an expansion of the various quantities of the theory in terms of matrix elements calculated with positive- and negative-energy spinors parametrized with the vacuum mass. Although the decrease in the mass upon going from vacuum to nuclear matter at the equilibrium density is quite large (approx.400 MeV), we are still able to exhibit a small parameter which allows for a perturbative expansion of the binding energy and other observables. The leading term in such an expansion reproduces the approximation widely used in other calculations of the properties of nuclear matter. The truncation of the expansion at the leading term is inadequate and this fact accounts for the lack of success in previous calculations using the standard formalism. We proceed to make a transformation to the Weinberg Lagrangian retaining the fluctuating parts of the sigma field. We further make a small-oscillation approximation, dropping the nonlinear terms in this Lagrangian

  4. Structural integrity evaluation of nuclear piping cracket

    International Nuclear Information System (INIS)

    Cadiz Deleito, J.C.

    1985-01-01

    The methodology to evaluation of cracks in nuclear piping is exposed. Linear elastic fracture mechanic is used to prediction of growing crack and the net section collapse theory compared with acceptation criteria of both ASME III and ASME XI code. A case allowable under ASME XI criteria is analysed under ASME III requirements. Consideration must be given to local phenomenon in crack area and local stress evaluated and compared with ASME III acceptation criteria. (author)

  5. Medium energy probes and nuclear structure

    International Nuclear Information System (INIS)

    Ginocchio, J.N.

    1984-01-01

    In this paper we explore two topics. The first topic is the marriage of medium energy reaction theory with the interacting boson model of nuclei in such a way that the multiple scattering is summed to all orders. The second topic is an exactly solvable potential model which gives realistic shell model eigenfunctions which can be used to calculate static and transition nuclear densities. (orig./HSI)

  6. Atomic parity nonconservation: Electroweak parameters and nuclear structure

    International Nuclear Information System (INIS)

    Pollock, S.J.; Fortson, E.N.; Wilets, L.

    1992-01-01

    There have been suggestions to measure atomic parity nonconservation (PNC) along an isotopic chain, by taking ratios of observables in order to cancel complicated atomic-structure effects. Precise atomic PNC measurements could make a significant contribution to tests of the standard model at the level of one-loop radiative corrections. However, the results also depend upon certain features of nuclear structure, such as the spatial distribution of neutrons in the nucleus. To examine the sensitivity to nuclear structure, we consider the case of Pb isotopes using various recent relativistic and nonrelativistic nuclear model calculations. Contributions from nucleon internal weak structure are included, but found to be fairly negligible. The spread among present models in predicted sizes of nuclear-structure effects may preclude using Pb isotope ratios to test the standard model at better than a 1% level, unless there are adequate independent tests of the nuclear models by various alternative strong and electroweak nuclear probes. On the other hand, sufficiently accurate atomic PNC experiments would provide a unique method to measure neutron distributions in heavy nuclei

  7. Structural integrity monitoring of critical components in nuclear facilities

    International Nuclear Information System (INIS)

    Roth, Maria; Constantinescu, Dan Mihai; Brad, Sebastian; Ducu, Catalin; Malinovschi, Viorel

    2007-01-01

    Full text: The paper presents the results obtained as part of the Project 'Integrated Network for Structural Integrity Monitoring of Critical Components in Nuclear Facilities', RIMIS, a research work underway within the framework of the Ministry of Education and Research Programme 'Research of Excellence'. The main objective of the Project is to constitute a network integrating the national R and D institutes with preoccupations in the structural integrity assessment of critical components in the nuclear facilities operating in Romania, in order to elaborate a specific procedure for this field. The degradation mechanisms of the structural materials used in the CANDU type reactors, operated by Unit 1 and Unit 2 at Cernavoda (pressure tubes, fuel elements sheaths, steam generator tubing) and in the nuclear facilities relating to reactors of this type as, for instance, the Hydrogen Isotopes Separation facility, will be investigated. The development of a flexible procedure will offer the opportunity to extend the applications to other structural materials used in the nuclear field and in the non-nuclear fields as well, in cooperation with other institutes involved in the developed network. The expected results of the project will allow the integration of the network developed at national level in the structures of similar networks operating within the EU, the enhancement of the scientific importance of Romanian R and D organizations as well as the increase of our country's contribution in solving the major issues of the nuclear field. (authors)

  8. Nuclear reactor structural material forming less radioactive corrosion product

    International Nuclear Information System (INIS)

    Nakazawa, Hiroshi.

    1988-01-01

    Purpose: To provide nuclear reactor structural materials forming less radioactive corrosion products. Constitution: Ni-based alloys such as inconel alloy 718, 600 or inconel alloy 750 and 690 having excellent corrosion resistance and mechanical property even in coolants at high temperature and high pressure have generally been used as nuclear reactor structural materials. However, even such materials yield corrosion products being attacked by coolants circulating in the nuclear reactor, which produce by neutron irradiation radioactive corrosion products, that are deposited in primary circuit pipeways to constitute exposure sources. The present invention dissolves dissolves this problems by providing less activating nuclear reactor structural materials. That is, taking notice on the fact that Ni-58 contained generally by 68 % in Ni changes into Co-58 under irradiation of neutron thereby causing activation, the surface of nuclear reactor structural materials is applied with Ni plating by using Ni with a reduced content of Ni-58 isotopes. Accordingly, increase in the radiation level of the nuclear reactor structural materials can be inhibited. (K.M.)

  9. Nuclear shapes and nuclear structure at low excitation energies. Abstracts of contributed papers

    International Nuclear Information System (INIS)

    Dykstra, F.; Goutte, D.; Sauvage, J.; Vergnes, M.

    1994-01-01

    103 papers are presented on recent theoretical and experimental results on nuclear structure investigation. Short communications were published in this volume, all of which were indexed separately for the INIS database. (R.P.)

  10. Investigations of nuclear structure and nuclear reactions induced by complex projectiles

    International Nuclear Information System (INIS)

    Sarantites, D.G.

    1991-01-01

    The research program of our group touches five areas of nuclear physics: (1) Nuclear structure studies at high spin; (2) Studies at the interface between structure and reactions; (3) Production and study of hot nuclei; (4) Incomplete fusion and fragmentation reactions; and (5) Development and use of novel techniques and instrumentation in the above areas of research. The papers from these areas are discussed in this report

  11. Experimental research of isospin and spin exotic nuclei with an ion guide and γ multidetectors

    International Nuclear Information System (INIS)

    Astier, A.

    1992-04-01

    This work is concerned with nuclear studies of isospin and spin exotic nuclei by two complementary approaches: on-line radioactivity and fusion-evaporation reactions. An ion guide coupled to the SARA accelerator allowed the study of very refractory and short lived (down to 1 ms) elements. Using the 238 U (α 40 MeV, f) reaction to produce very neutron-rich radioisotopes, all mass chains from A=96 to 122 have been scanned by conventional nuclear spectroscopy. More than 60 production yields have been measured. The comparison of proton and α induced fission yields shows the predominance of symmetric fission around A=115 for α beam. The collective high spin states structures observed in the A=190 mass region are studied with different γ multidetectors

  12. Nuclear structure at high-spin and large-deformation

    International Nuclear Information System (INIS)

    Shimizu, Yoshifumi R.

    2000-01-01

    Atomic nucleus is a finite quantal system and shows various marvelous features. One of the purposes of the nuclear structure study is to understand such features from a microscopic viewpoint of nuclear many-body problem. Recently, it is becoming possible to explore nuclear states under 'extreme conditions', which are far different from the usual ground states of stable nuclei, and new aspects of such unstable nuclei attract our interests. In this lecture, I would like to discuss the nuclear structure in the limit of rapid rotation, or the extreme states with very large angular momenta, which became accessible by recent advent of large arrays of gamma-ray detecting system; these devices are extremely useful to measure coincident multiple γ-rays following heavy-ion fusion reactions. Including such experimental aspects as how to detect the nuclear rotational states, I review physics of high-spin states starting from the elementary subjects of nuclear structure study. In would like also to discuss the extreme states with very large nuclear deformation, which are easily realized in rapidly rotating nuclei. (author)

  13. Grid structure for nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    Wachter, W.J.; Akey, J.G.

    1975-01-01

    Described is a nuclear fuel element support system comprising an egg-crate-type grid made up of slotted vertical portions interconnected at right angles to each other, the vertical portions being interconnected by means of cross straps which are dimpled midway between their ends to engage fuel elements disposed within openings formed in the egg-crate assembly. The cross straps are disposed at an angle, other than a right angle, to the vertical portions of the assembly whereby their lengths are increased for a given span, and the total elastic deflection capability of the cell is increased. The assembly is particularly adapted for computer design and automated machine tool fabrication

  14. Romanian network for structural integrity assessment of nuclear components

    International Nuclear Information System (INIS)

    Roth, Maria; Constantinescu, Dan Mihai; Brad, Sebastian; Ducu, Catalin

    2008-01-01

    Full text: Based of the Romanian option to develop and operate nuclear facilities, using as model the networks created at European level and taking into account the international importance of the structural integrity assessments for lifetime extension of the nuclear components, a national Project started since 2005 in the framework of the National Program 'Research of Excellence', Modulus I 2006-2008, managed by the Ministry of Education and Research. Entitled 'Integrated Network for Structural Integrity Monitoring of Critical Components in Nuclear Facilities', with the acronym RIMIS, the Project had two main objectives: - to elaborate a procedure applicable to the structural integrity assessment of the critical components used in Romanian nuclear facilities; - to integrate the national networking in a similar one, at European level, to enhance the scientific significance of Romanian R and D organizations as well as to increase the contribution to solving one of the major issue of the nuclear field. The paper aimed to present the activities performed in the Romanian institutes, involved in the Project, the final results obtained as part of the R and D activities, including experimental, theoretical and modeling ones regarding structural integrity assessment of nuclear components employed in CANDU type reactors. Also the activity carried out in the framework of the NULIFE network, created at European level of the FP6 Program and sustained by the RIMIS network will be described. (authors)

  15. Investigations of nuclear structure and nuclear reactions induced by complex projectiles. Technical progress report, November 1, 1978-October 31, 1979

    International Nuclear Information System (INIS)

    Sarantites, D.G.

    1979-01-01

    Experimental research on nuclear structure and reactions both published and in progress is summarized. Included are fusion reactions, strongly damped heavy ion collisions, and nuclear structure at high angular momentum. A list of publications is included

  16. Activities report 1991-1992: Nuclear Research Center of Strasbourg

    International Nuclear Information System (INIS)

    1993-01-01

    This activities report of the Nuclear Research Centre of Strasbourg for the years 1991 and 1992, presents nine research axis: theoretical physics, mechanisms of reactions and nuclear structure, extreme forms of nuclei, exotic nuclei, hot and dense nuclear matter, ultra-relativistic heavy ions, physics of LEP (European Large Electron-Positron storage ring) at 'DELPHI', chemistry and physics of radiations, physics and applications of semi-conductors

  17. Status of the evaluated nuclear structure data file

    International Nuclear Information System (INIS)

    Martin, M.J.

    1991-01-01

    The structure, organization, and contents of the Evaluated Nuclear Structure Data File (ENSDF) are discussed in this paper. This file contains a summary of the state of experimental nuclear structure data for all nuclides as determined from consideration of measurements reported worldwide in the literature. Special emphasis is given to the data evaluation procedures, the consistency checks, and the quality control utilized at the input stage and to the retrieval capabilities of the system at the output stage. Recent enhancements of the on-line interaction with the file contents is addressed as well as procedural changes that will improve the currency of the file

  18. Dynamic testing of nuclear power plant structures: an evaluation

    International Nuclear Information System (INIS)

    Weaver, H.J.

    1980-02-01

    Lawrence Livermore Laboratory (LLL) evaluated the applications of system identification techniques to the dynamic testing of nuclear power plant structures and subsystems. These experimental techniques involve exciting a structure and measuring, digitizing, and processing the time-history motions that result. The data can be compared to parameters calculated using finite element or other models of the test systems to validate the model and to verify the seismic analysis. This report summarizes work in three main areas: (1) analytical qualification of a set of computer programs developed at LLL to extract model parameters from the time histories; (2) examination of the feasibility of safely exciting nuclear power plant structures and accurately recording the resulting time-history motions; (3) study of how the model parameters that are extracted from the data be used best to evaluate structural integrity and analyze nuclear power plants

  19. The structure of nuclear safeguards systems

    International Nuclear Information System (INIS)

    Coulter, C.A.

    1989-01-01

    Safeguards systems for facilities that handle special nuclear material combine procedural, protective, and materials accounting elements to prevent and/or detect sabotage and diversion or theft of material. Because most of the discussion in this course is devoted to materials accounting topics only, this chapter provides a brief introduction to some of the procedural and protective elements of safeguards systems, placing the materials accounting system in its proper context. The chapter begins by reviewing certain pertinent DOE definitions and then surveys some protection requirements and technology - protective personnel, personnel identification systems, barriers, detectors, and communication systems. Considered next are the procedures of personnel selection and monitoring, definition and division of job functions, and operation. The chapter then describes the way the procedural, protective, and materials accounting elements can be combined, becoming a total safeguards system. Although such a system necessarily requires elements of procedure, protection, and materials accounting, only the materials accounting gives positive assurance that nuclear material is not diverted or stolen

  20. Ecosystem impacts of exotic annual invaders in the genus Bromus

    Science.gov (United States)

    Matthew J. Germino; Jayne Belnap; John M. Stark; Edith B Allen; Benjamin Rau

    2016-01-01

    An understanding of the impacts of exotic plant species on ecosystems is necessary to justify and guide efforts to limit their spread, restore natives, and plan for conservation. Invasive annual grasses such as Bromus tectorum, B. rubens, B. hordeaceus, and B. diandrus (hereafter collectively referred to as Bromus) transform the structure and function of ecosystems...

  1. The effects of exotic weed Flaveria bidentis with different invasion ...

    African Journals Online (AJOL)

    A new exotic weed, Flaveria bidentis, is spreading in central China where it forms dense monospecific patches modifying the structure of different native ecosystems and threatening native aboveground biodiversity. However, little is known about the consequences of such an invasion for soil bacterial community, especially ...

  2. Structuring Cooperative Nuclear RIsk Reduction Initiatives with China.

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, Larry [Stanford Univ., CA (United States); Reinhardt, Jason Christian [Stanford Univ., CA (United States); Hecker, Siegfried [Stanford Univ., CA (United States)

    2017-03-01

    The Stanford Center for International Security and Cooperation engaged several Chinese nuclear organizations in cooperative research that focused on responses to radiological and nuclear terrorism. The objective was to identify joint research initiatives to reduce the global dangers of such threats and to pursue initial technical collaborations in several high priority areas. Initiatives were identified in three primary research areas: 1) detection and interdiction of smuggled nuclear materials; 2) nuclear forensics; and 3) radiological (“dirty bomb”) threats and countermeasures. Initial work emphasized the application of systems and risk analysis tools, which proved effective in structuring the collaborations. The extensive engagements between national security nuclear experts in China and the U.S. during the research strengthened professional relationships between these important communities.

  3. Generalized Nuclear Data: A New Structure (with Supporting Infrastructure) for Handling Nuclear Data

    International Nuclear Information System (INIS)

    Mattoon, C.M.; Beck, B.R.; Patel, N.R.; Summers, N.C.; Hedstrom, G.W.; Brown, D.A.

    2012-01-01

    The Evaluated Nuclear Data File (ENDF) format was designed in the 1960s to accommodate neutron reaction data to support nuclear engineering applications in power, national security and criticality safety. Over the years, the scope of the format has been extended to handle many other kinds of data including charged particle, decay, atomic, photo-nuclear and thermal neutron scattering. Although ENDF has wide acceptance and support for many data types, its limited support for correlated particle emission, limited numeric precision, and general lack of extensibility mean that the nuclear data community cannot take advantage of many emerging opportunities. More generally, the ENDF format provides an unfriendly environment that makes it difficult for new data evaluators and users to create and access nuclear data. The Cross Section Evaluation Working Group (CSEWG) has begun the design of a new Generalized Nuclear Data (or 'GND') structure, meant to replace older formats with a hierarchy that mirrors the underlying physics, and is aligned with modern coding and database practices. In support of this new structure, Lawrence Livermore National Laboratory (LLNL) has updated its nuclear data/reactions management package Fudge to handle GND structured nuclear data. Fudge provides tools for converting both the latest ENDF format (ENDF-6) and the LLNL Evaluated Nuclear Data Library (ENDL) format to and from GND, as well as for visualizing, modifying and processing (i.e., converting evaluated nuclear data into a form more suitable to transport codes) GND structured nuclear data. GND defines the structure needed for storing nuclear data evaluations and the type of data that needs to be stored. But unlike ENDF and ENDL, GND does not define how the data are to be stored in a file. Currently, Fudge writes the structured GND data to a file using the eXtensible Markup Language (XML), as it is ASCII based and can be viewed with any text editor. XML is a meta-language, meaning that it

  4. Generalized Nuclear Data: A New Structure (with Supporting Infrastructure) for Handling Nuclear Data

    Energy Technology Data Exchange (ETDEWEB)

    Mattoon, C.M. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA (United States); Beck, B.R.; Patel, N.R.; Summers, N.C.; Hedstrom, G.W. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA (United States); Brown, D.A. [National Nuclear Data Center, Upton NY (United States)

    2012-12-15

    The Evaluated Nuclear Data File (ENDF) format was designed in the 1960s to accommodate neutron reaction data to support nuclear engineering applications in power, national security and criticality safety. Over the years, the scope of the format has been extended to handle many other kinds of data including charged particle, decay, atomic, photo-nuclear and thermal neutron scattering. Although ENDF has wide acceptance and support for many data types, its limited support for correlated particle emission, limited numeric precision, and general lack of extensibility mean that the nuclear data community cannot take advantage of many emerging opportunities. More generally, the ENDF format provides an unfriendly environment that makes it difficult for new data evaluators and users to create and access nuclear data. The Cross Section Evaluation Working Group (CSEWG) has begun the design of a new Generalized Nuclear Data (or 'GND') structure, meant to replace older formats with a hierarchy that mirrors the underlying physics, and is aligned with modern coding and database practices. In support of this new structure, Lawrence Livermore National Laboratory (LLNL) has updated its nuclear data/reactions management package Fudge to handle GND structured nuclear data. Fudge provides tools for converting both the latest ENDF format (ENDF-6) and the LLNL Evaluated Nuclear Data Library (ENDL) format to and from GND, as well as for visualizing, modifying and processing (i.e., converting evaluated nuclear data into a form more suitable to transport codes) GND structured nuclear data. GND defines the structure needed for storing nuclear data evaluations and the type of data that needs to be stored. But unlike ENDF and ENDL, GND does not define how the data are to be stored in a file. Currently, Fudge writes the structured GND data to a file using the eXtensible Markup Language (XML), as it is ASCII based and can be viewed with any text editor. XML is a meta-language, meaning that it

  5. Apparatus for securing structural tubes in nuclear reactor fuel assemblies

    International Nuclear Information System (INIS)

    Kerry, J.S.

    1987-01-01

    This patent describes a nuclear reactor fuel assembly having a structural tube with a predetermined inside diameter, a generally cylindrical insert of an axial length substantially smaller than the axial length of the structural tube and having a generally cylindrical passageway of a predetermined diameter smaller than the predetermined inside diameter for providing an effectively reduced inside diameter for the structural tube. The insert comprises: means, having an outside diameter approximately equal to the predetermined inside diameter, for coaxially centering the insert within the structural tube; forming lobes, operable when expanded to locally deform against the structural tube thereby locking the insert within the structural tube

  6. Charge-exchange giant resonances as probes of nuclear structure

    International Nuclear Information System (INIS)

    Blomgren, J.

    2001-09-01

    Giant resonances populated in charge-exchange reactions can reveal detailed information about nuclear structure properties, in spite of their apparent featurelessness. The (p,n) and (n,p) reactions - as well as their analog reactions - proceed via the same nuclear matrix element as beta decay. Thereby, they are useful for probing electroweak properties in nuclei, especially for those not accessible to beta decay. The nuclear physics aspects of double beta decay might be investigated in double charge-exchange reactions. detailed nuclear structure information, such as the presence of ground-state correlations, can be revealed via identification of 'first-forbidden' transitions. In addition, astrophysics aspects and halo properties of nuclei have been investigated in charge exchange. Finally, these experiments have questioned our knowledge of the absolute strength of the strong interaction

  7. ISINN-2. Neutron spectroscopy, nuclear structure and related topics

    International Nuclear Information System (INIS)

    1994-01-01

    The proceedings contain the materials presented at the Second International Seminar on Neutron-Nucleus Interactions (ISINN-2) dealing with the problems of neutron spectroscopy, nuclear structure and related topics. The Seminar took place in Dubna on April 26-28, 1994. Over 120 scientists from Belgium, Bulgaria, Czech Republic, Germany, Holland, Italy, Japan, Latvia, Mexico, Poland, Slovakia, Slovenia, Ukraine, US and about 10 Russian research institutes took part in the Seminar. The main problems discussed are the following: P-odd and P-even angular correlation and T-reversal invariance in neutron reactions, nuclear structure investigations by neutron capture, the mechanism of neutron reactions, nuclear fission processes, as well as neutron data for nuclear astrophysics

  8. Exotic quantum states for charmed baryons at finite temperature

    Directory of Open Access Journals (Sweden)

    Jiaxing Zhao

    2017-12-01

    Full Text Available The significantly screened heavy-quark potential in hot medium provides the possibility to study exotic quantum states of three-heavy-quark systems. By solving the Schrödinger equation for a three-charm-quark system at finite temperature, we found that, there exist Borromean states which might be realized in high energy nuclear collisions, and the binding energies of the system satisfy precisely the scaling law for Efimov states in the resonance limit.

  9. Structure of nuclear fuel data bank

    International Nuclear Information System (INIS)

    Silva Matos Pombo, J.B. da; Andrade, M.C. de

    1990-01-01

    A data Base structure for power reactor fuel elements operational performance and fabrication data storage, is described. The current structure with the listing of all 44 tables that contain a total of 338 data fields is presented. The general purpose of each table is shortly described. The structure was tested in microcomputer with the aid of short hypothetical data sets and the results were regarded as satisfactory. Some examples of typical inquiries made during the tests are also presented. The presented work is directed on implementing this structure in microcomputer under the 'PARADOX' data base management system. Subroutines to represent fuel element and core lattice were implemented in order to display, in the lattice cells, the data of fields selected by the user. (author) [pt

  10. Complementarity between neutron capture and heavy-ion reactions in nuclear structure studies

    International Nuclear Information System (INIS)

    Schult, O.W.B.

    1978-01-01

    The study of the complementarity of certain nuclear reactions in nuclear structure studies includes spectroscopic methods, nuclear rotation and coupling of nucleons to the core, and the de-excitation and structure of high lying states. 23 references

  11. Bottomonium, charmonium and exotic states

    International Nuclear Information System (INIS)

    Nakao, M.

    2014-01-01

    Heavy quarkonia states have been extensively studied in the past decade by B-factories and other experiments, and have provided many surprises that suggest that our understanding of the meson is still incomplete. The recent BaBar and Belle data filled many of the missing seats in the bottomonium table such as η b or h b , while LHC experiments are also contributing, for example in the observation of χ b (3P) state by ATLAS. There are clear signs of exotic states, such as the charged Z b + and Z c + found by Belle, yet puzzling X(3872), and overpopulated Y state series. Recent progress on the bottomonium, charmonium and exotic states is discussed in this review. (author)

  12. Nuclear Pore-Like Structures in a Compartmentalized Bacterium.

    Directory of Open Access Journals (Sweden)

    Evgeny Sagulenko

    Full Text Available Planctomycetes are distinguished from other Bacteria by compartmentalization of cells via internal membranes, interpretation of which has been subject to recent debate regarding potential relations to Gram-negative cell structure. In our interpretation of the available data, the planctomycete Gemmata obscuriglobus contains a nuclear body compartment, and thus possesses a type of cell organization with parallels to the eukaryote nucleus. Here we show that pore-like structures occur in internal membranes of G.obscuriglobus and that they have elements structurally similar to eukaryote nuclear pores, including a basket, ring-spoke structure, and eight-fold rotational symmetry. Bioinformatic analysis of proteomic data reveals that some of the G. obscuriglobus proteins associated with pore-containing membranes possess structural domains found in eukaryote nuclear pore complexes. Moreover, immunogold labelling demonstrates localization of one such protein, containing a β-propeller domain, specifically to the G. obscuriglobus pore-like structures. Finding bacterial pores within internal cell membranes and with structural similarities to eukaryote nuclear pore complexes raises the dual possibilities of either hitherto undetected homology or stunning evolutionary convergence.

  13. Structural dynamic and resistance to nuclear air blast

    International Nuclear Information System (INIS)

    Qureshi, S.M.

    2003-01-01

    A need exists to design protective shelters attached to specialized facilities against nuclear airbursts, explosive shocks and impacting projectiles. Designing such structures against nuclear and missile impact is a challenging task that needs to be looked into for design methodology formulation and practicability. Structures can be designed for overpressure pulsed generated by a nuclear explosion as well as the scabbing and perforation/punching of an impacting projectile. This paper discuses and formulates the methods of dynamic analysis and design required to undertake such a task. Structural resistance to peak overpressure pulse for a 20 KT weapons and smaller tactical nuclear weapons of 1 KT (16 psi, overpressure) size as a direct air blast overpressure has been considered in design of walls, beams and slabs of a special structure under review. The design of shear reinforcement as lacing is also carried out. Adopting the philosophy of strengthening and hardening can minimize the effect of air blast overpressure and projectile impact. The objective is to avoid a major structural failure. The structure then needs to be checked against ballistic penetration by a range of weapons or be required to resist explosive penetration from the charge detonated in contact with the structure. There is also a dire need to formulate protective guidelines for all existing and future critical facilities. (author)

  14. Workshop on nuclear structure and decay data evaluation. Summary report

    International Nuclear Information System (INIS)

    Pronyaev, V.G.; Nichols, A.L.

    2003-01-01

    A summary is given of the aims and contents of the Workshop on Nuclear Structure and Decay Data (NSDD) Evaluation, including the agenda, lists of participants and their presentations, general comments and recommendations. The 1-week workshop was organized by the IAEA Nuclear Data Section, and held in Vienna, Austria, from 18 to 22 November 2002. Workshop material, including participants' presentations, computer codes, manuals and other materials for NSDD evaluators, are freely available on CD-ROM on request. (author)

  15. Structural integrity of materials in nuclear service: a bibliography

    International Nuclear Information System (INIS)

    Heddleson, F.A.

    1977-01-01

    This report contains 679 abstracts from the Nuclear Safety Information Center (NSIC) computer file dated 1973 through 1976 covering material properties with respect to structural integrity. All materials important to the nuclear industry (except concrete) are covered for mechanical properties, chemical properties, corrosion, fracture or failure, radiation damage, creep, cracking, and swelling. Keyword, author, and permuted-title indexes are included for the convenience of the user

  16. Structural integrity of materials in nuclear service: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Heddleson, F.A.

    1977-06-07

    This report contains 679 abstracts from the Nuclear Safety Information Center (NSIC) computer file dated 1973 through 1976 covering material properties with respect to structural integrity. All materials important to the nuclear industry (except concrete) are covered for mechanical properties, chemical properties, corrosion, fracture or failure, radiation damage, creep, cracking, and swelling. Keyword, author, and permuted-title indexes are included for the convenience of the user.

  17. RATU - Nuclear power plant structural safety

    International Nuclear Information System (INIS)

    Hedner, G.; Schultz, H.; Unneberg, L.

    1992-12-01

    The evaluation group is of the opinion that the work performed under the RATU programme is generally of high quality, in some areas, especially those related to water chemistry of excellent quality. The personnel gives the impression of being dedicated and enthusiastic, and the administration seems to be very effective. It is obvious that the RATU programme has taken advantage of related contracts and projects funded by different sources. It is the opinion of the valuation group that the investment and human capital have been brought to work very efficiently in all projects. The objectives of the programme and the different projects are formulated in a broad sense. The areas selected for work are however of high relevance to nuclear safety. In some projects not all aspects are addressed by the ongoing work, and further activities may be necessary to meet with the requirements of the authorities. (orig.)

  18. Nuclear molecular structure in heavy mass systems

    International Nuclear Information System (INIS)

    Arctaedius, T.; Bargholtz, C.

    1989-04-01

    A study is made of nuclear molecular configurations involving one heavy mass partner. The stability of these configurations to mass flow and to fission is investigated as well as their population in fusion reactions. It is concluded that shell effects in combination with the effects of angular momentum may be important in stabilizing certain configurations. A possible relation of these configurations to the so called superdeformed states is pointed out. The spectrum of rotational and vibrational trasitions within molecular configurations is investigated. For sufficiently mass-asymmetric systems the engergies of vibrational transitions are comparable to the neutron separation energy. Gamma radiation from such transitions may then be observable above the background of statistical transitions. The gamma spectrum and the directional distribution of the radioation following fusion reactions with 12 C and 16 O are calculated. (authors)

  19. Exotic Small Mammals and Bartonella

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dr. Nina Marano discusses Bartonella, a bacterial agent that’s prevalent in many species, including cats, dogs, and cattle. Wild animals are normally thought to carry Bartonella, so when animals are caught in the wild for pet trade, the risk that humans can become infected with Bartonella increases. Bartonella is an identified risk associated with ownership of exotic animals and has serious health consequences.

  20. An exotic composite vector boson

    International Nuclear Information System (INIS)

    Akama, Keiichi; Hattori, Takashi; Yasue, Masaki.

    1990-08-01

    An exotic composite vector boson, V, is introduced in two dynamical models of composite quarks, leptons, W and Z. One is based on four Fermi interactions, in which composite vector bosons are regarded as fermion-antifermion bound states and the other is based on the confining SU(2) L gauge model, in which they are given by scalar-antiscalar bound states. Both approaches describe the same effective interactions for the sector of composite quarks, leptons, W, Z, γ and V. (author)

  1. Exotic phases in neutron stars

    International Nuclear Information System (INIS)

    Li, A.; Burgio, G.F.; Lombardo, U.; Peng, G.X.

    2008-01-01

    The appearance of exotic phases in neutron stars is studied. The possible transition from hadron to quark phase is studied within the density dependent mass quark model, and the kaon condensation within the Nelson and Kaplan model. In both cases a microscopic approach is adopted for dense hadron matter. From the study of the possible coexistence between the two phases it is found that the hybrid phase may strongly hinder the onset of kaon condensation. (author)

  2. Micro-structured nuclear fuel and novel nuclear reactor concepts for advanced power production

    International Nuclear Information System (INIS)

    Popa-Simil, Liviu

    2008-01-01

    Many applications (e.g. terrestrial and space electric power production, naval, underwater and railroad propulsion and auxiliary power for isolated regions) require a compact-high-power electricity source. The development of such a reactor structure necessitates a deeper understanding of fission energy transport and materials behavior in radiation dominated structures. One solution to reduce the greenhouse-gas emissions and delay the catastrophic events' occurrences may be the development of massive nuclear power. The actual basic conceptions in nuclear reactors are at the base of the bottleneck in enhancements. The current nuclear reactors look like high security prisons applied to fission products. The micro-bead heterogeneous fuel mesh gives the fission products the possibility to acquire stable conditions outside the hot zones without spilling, in exchange for advantages - possibility of enhancing the nuclear technology for power production. There is a possibility to accommodate the materials and structures with the phenomenon of interest, the high temperature fission products free fuel with near perfect burning. This feature is important to the future of nuclear power development in order to avoid the nuclear fuel peak, and high price increase due to the immobilization of the fuel in the waste fuel nuclear reactor pools. (author)

  3. The policy structure of the Dutch nuclear energy sector

    International Nuclear Information System (INIS)

    Zijlstra, G.J.

    1982-01-01

    The main objective of this study has been to indicate the principle structures through which much of governmental nuclear policy is formed and to develop a model for the analysis of policy communication networks. The first chapter begins with a general outline of the international development of nuclear energy and gives an impression of the Dutch nuclear energy sector with special emphasis on the institutional aspects. In chapter II the author elaborates on the place of structural analysis in public policy analysis and argues that it is one of the indispensable elements of public policy analysis. Relations are treated in chapter III. Personal interlocks are given special attention because these are interrelated with financial, informational and other dependency relations and have a special communicative function in public policy-making. The different functions of the interlocks are 'translated' in graph theoretical concepts. Chapter IV introduces a method derived from graph analysis to analyse public policy networks. Several structural configurations are distinguished. In the same chapter an outline of the empirical research on the nuclear energy network will be given. In chapters V and VI the nuclear energy network is analysed, and in chapter VII the decision-making concerning some nuclear items is described in a general way. (Auth.)

  4. Development of deterioration models and tests of structural materials for nuclear containment structures(III)

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Byung Hwan [Seoul National University, Seoul (Korea)

    2002-03-01

    The nuclear containment structures are very important infrastructures which require much cost for construction and maintenance. If these structures lose their functions and do not ensure their safety, great losses of human lives and properties will result. Therefore, the nuclear containment structures should secure appropriate safety and functions during these service lives. The nuclear concrete structures start to experience deterioration due to severe environmental condition, even though the concrete structures exhibit generally superior durability. It is, therefore, necessary to take appropriate actions at each stage of planning, design and construction to secure safety and functionability. Thorough examination of deterioration mechanism and comprehensive tests have been conducted to explore the durability characteristics of nuclear concrete structures. 88 refs., 70 figs., 12 tabs. (Author)

  5. Future of structural reliability methodology in nuclear power plant technology

    Energy Technology Data Exchange (ETDEWEB)

    Schueeller, G I [Technische Univ. Muenchen (Germany, F.R.); Kafka, P [Gesellschaft fuer Reaktorsicherheit m.b.H. (GRS), Garching (Germany, F.R.)

    1978-10-01

    This paper presents the authors' personal view as to which areas of structural reliability in nuclear power plant design need most urgently to be advanced. Aspects of simulation modeling, design rules, codification and specification of reliability, system analysis, probabilistic structural dynamics, rare events and particularly the interaction of systems and structural reliability are discussed. As an example, some considerations of the interaction effects between the protective systems and the pressure vessel are stated. The paper concludes with recommendation for further research.

  6. Nuclear structure at intermediate energies. Progress report

    International Nuclear Information System (INIS)

    Bonner, B.E.; Mutchler, G.S.

    1992-01-01

    We report here oil the progress that we made for the nine months beginning October 1, 1991 for DOE Grant No. DE-FG05-87ER40309. The report covers the third year of a three year grant. Since we are submitting an accompanying Grant Renewal Proposal, we provide in this report more background information than usual for the different projects. The theme that unites the experiments undertaken by the Bonner Lab Medium Energy Group is a determination to understand in detail the many facets and manifestations of the strong interaction, that which is now referred to as nonperturbative QCD. Whether we are investigating the question of just what does carry the spin of baryons, or the extent of the validity of the SU(6) wavefunctions for the excited hyperons (as will be measured in our CEBAF experiment), or questions associated with the formation of a new state of matter predicted by QCD (the subject of AGS bar p experiment E854, AGS heavy ion experiment E810, as-well as the approved STAR experiment at RHIC), - all these projects share this common goal. FNAL E683 may well open a new field of investigation in nuclear physics: That of just how colored quarks and gluons interact with nuclear matter as they traverse nuclei of different-sizes. In most all of the experiments mentioned, above, the Bonner Lab Group is playing major leadership roles as well as doing a big fraction of the hard work that such experiments require. We use many of the facilities that are available to the intermediate energy physics community and we use our expertise to design and fabricate the detectors and instrumentation that are required to perform the measurements which we decide to do. The format we follow in the Progress Report is,to provide a concise, but fairly complete write-up on each project. The publications listed in Section In give much greater detail on many of the projects. The aim in this report is to focus on the physics goals, the results, and their significance

  7. Structure of high excited nuclear states and elastic scattering

    International Nuclear Information System (INIS)

    Zhivopistsev, F.A.; Rzhevskij, E.S.

    1979-01-01

    An approach to a unified description of nuclear reactions and nuclear structure based on the formalism of the quantum Green functions and on the ideas of the theory of finite Fermi systems has been formulated. New structural vertices are introduced, which are responsible for nucleon collectivization in an atomic nucleus and for the excitation of many-phonon, quasideuteron, quasitriton and other configurations. The vertices define both the processes of particle scattering by atomic nuclei (T matrix and optical potentials) and the nuclear structure (secular equations and wave functions). The vertices are determined from the equations with effective many-particle forces Fsub(nm)sup(c). In their turn the Fsub(nm)sup(c) forces are either determined from a comparison of theory and experiment, or calculated from the equations with more fundamental nucleon-nucleon forces in a nucleus. The effective forces Fsub(nm)sup(c) are more universal than the constants of the theory of finite Fermi-systems, which extends the boundaries of applicability of the particle-hole formalism in the description of nuclear processes. In this approach the traditional methods of description of the nuclear structure, based on particular models of hamiltonian and wave functions, acquire a natural interpretation

  8. Investigation of nuclear structures using transition probabilities

    CERN Document Server

    Dewald, A; Peusquens, R

    2002-01-01

    Magnetic rotation which appears as regular M1 bands in the spectra, is a well established phenomenon in several Pb isotopes. In the A = 130 region where similar M1 bands are known, e.g. in sup 1 sup 2 sup 4 Xe and sup 1 sup 2 sup 8 Ba, it is still not clear whether it does exists. Crucial experimental observables are the B (M1) values which -are expected to decrease with in creasing spin. At Strasbourg a recoil distance measurement (RDM) with the EUROBALL spectrometer at Strasbourg and the Koeln plunger using the reaction sup 1 sup 1 sup 0 Pd( sup 1 sup 8 O, 4n) sup 1 sup 2 sup 4 Xe at a beam energy of 86 MeV yielded preliminary lifetimes of ground band states and states of the M1 band. The deduced B(M1) values show the expected behaviour for magnetic rotation. It is also shown that the experimental B(M1) values can be described as well on the basis of a rotational band. The measured B(E2) values are used to investigate the nuclear deformation of sup 1 sup 2 sup 4 Xe as well as the interaction of the ground s...

  9. Phenomenological correlations in nuclear structure: An opportunity for nuclear astrophysics and a challenge to theory

    International Nuclear Information System (INIS)

    Casten, R.F.; Zamfir, N.V.

    1992-01-01

    Though it often appears daunting in its complexity, nuclear data frequently exhibits remarkable simplicities when viewed from the appropriate perspectives. This realization, which is becoming more and more apparent, is one of the fruits of the vast amount of nuclear data that has been accumulated over many years but, surprisingly, has never been completely digested. This emerging, unified, and simple macroscopic phenomenology, aided by microscopic underpinnings and physical arguments, appears in many guises and often simplifies semi-empirical estimates of structure far from stability in the critical realms where nuclear astrophysics takes place and where it is in need for improved nuclear input. The generality of simple phenomenological relationships begs both for a sound theoretical basis and for the advent of Radioactive Nuclear Beams so that the reliability of their extrapolations can be assessed and tested. These issues will be discussed, and illustrated with a number of specific examples

  10. Structural design and dynamic analysis of underground nuclear reactor containments

    International Nuclear Information System (INIS)

    Kierans, T.W.; Reddy, D.V.; Heale, D.G.

    1975-01-01

    Present actual experience in the structural design of undeground containments is limited to only four rather small reactors all located in Europe. Thus proposals for future underground reactors depend on the transposition of applicable design specifications, constraints and criteria from existing surface nuclear power plants to underground, and the use of many years of experience in the structural design of large underground cavities and cavity complexes for other purposes such as mining, hydropower stations etc. An application of such considerations in a recent input for the Underground Containment sub-section of the Seismic Task Group Report to the ASCE Committee for Nuclear Structures and Materials is presented as follows: underground concept considerations, siting criteria and structural selection, structural types, analytical and semi-analytical approaches, design and other miscellaneous considerations

  11. Organization, structure, and performance in the US nuclear power industry

    International Nuclear Information System (INIS)

    Lester, R.K.

    1986-01-01

    Several propositions are advanced concerning the effects of industry organization and structure on the economic performance of the American commercial nuclear power industry. Both the electric utility industry and the nuclear power plant supply industry are relatively high degree of horizontal disaggregation. The latter is also characterized by an absence of vertical integration. The impact of each of these factors on construction and operating performance is discussed. Evidence is presented suggesting that the combination of horizontal and vertical disaggregation in the industry has had a significant adverse effect on economic performance. The relationship between industrial structure and regulatory behavior is also discussed. 43 references, 4 figures, 9 tables

  12. Status of transactinium nuclear data in the Evaluated Nuclear Structure Data File

    International Nuclear Information System (INIS)

    Ewbank, W.B.

    1979-01-01

    The organization and program of the Nuclear Data Project are described. An Evaluated Nuclear Structure Data File (ENSDF) was designed to contain most of the data of nuclear structure physics. ENSDF includes adopted level information for all 1950 known nuclei, and detailed data for approximately 1500 decay schemes. File organization, management, and retrieval are reviewed. An international network of data evaluation centers has been organized to provide for a four-year cycle of ENSDF revisions. Standard retrieval and display programs can prepare various tables of specific data, which can serve as a good first approximation to a complete up-to-date compilation. Appendixes list, for A > 206, nuclear levels with lifetimes > or = 1 s, strong γ rays from radioisotopes (ordered by nuclide and energy), and strong α particle emissions (similarly ordered). 8 figures

  13. Impact loads on nuclear power plant structures

    International Nuclear Information System (INIS)

    Riera, J.D.

    1993-01-01

    The first step in evaluation of a NPP design for protection against impact loading, is to identify those events that may be credible for a particular site. In connection with external, man-made events IAEA Safety Series No.50-SG-S5 provides a methodology for selecting the events that need to be considered. This presentation deals with modelling of interface forces in projectile impact against unyielding structures, vibrations induced by impact, penetration, scabbing and perforation effects

  14. Experimental investigations of the nuclear structure

    International Nuclear Information System (INIS)

    Gromov, K.Ya.

    1989-01-01

    The problem of experimental investigation into atomic nucleus structure is discussed. Examples of studying the properties of low-lying nucleus states using cyclotron-type accelerators for their production are presented. The consideration is conducted on the base of the Idisol experimental complex created at the Finland. Results of measuring masses of neutron-redundant rubidium nuclei are presented. Schemes of 160 Er and 108 In decay are presented. 12 refs.; 6 figs

  15. Algebraic fermion models and nuclear structure physics

    International Nuclear Information System (INIS)

    Troltenier, Dirk; Blokhin, Andrey; Draayer, Jerry P.; Rompf, Dirk; Hirsch, Jorge G.

    1996-01-01

    Recent experimental and theoretical developments are generating renewed interest in the nuclear SU(3) shell model, and this extends to the symplectic model, with its Sp(6,R) symmetry, which is a natural multi-(ℎ/2π)ω extension of the SU(3) theory. First and foremost, an understanding of how the dynamics of a quantum rotor is embedded in the shell model has established it as the model of choice for describing strongly deformed systems. Second, the symplectic model extension of the 0-(ℎ/2π)ω theory can be used to probe additional degrees of freedom, like core polarization and vorticity modes that play a key role in providing a full description of quadrupole collectivity. Third, the discovery and understanding of pseudo-spin has allowed for an extension of the theory from light (A≤40) to heavy (A≥100) nuclei. Fourth, a user-friendly computer code for calculating reduced matrix elements of operators that couple SU(3) representations is now available. And finally, since the theory is designed to cope with deformation in a natural way, microscopic features of deformed systems can be probed; for example, the theory is now being employed to study double beta decay and thereby serves to probe the validity of the standard model of particles and their interactions. A subset of these topics will be considered in this course--examples cited include: a consideration of the origin of pseudo-spin symmetry; a SU(3)-based interpretation of the coupled-rotor model, early results of double beta decay studies; and some recent developments on the pseudo-SU(3) theory. Nothing will be said about other fermion-based theories; students are referred to reviews in the literature for reports on developments in these related areas

  16. North Carolina State University Nuclear Structure Research at the Triangle Universities Nuclear Laboratory. Progress report

    International Nuclear Information System (INIS)

    Seagondollar, L.W.; Waltner, A.W.; Mitchell, G.E.; Tilley, D.R.; Gould, C.R.

    1975-01-01

    A summary is presented of nuclear structure research completed at the Triangle Universities Nuclear Lab for the period 9/1/74 to 8/31/75. Included are abstracts and titles for studies of electromagnetic transitions in low-medium mass nuclei, high resolution studies, accelerator induced x-ray investigations, and energy related neutron and charged particle cross section measurements. (U.S.)

  17. Aging management of containment structures in nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.; Graves, H.L. III; Norris, W.E.

    1996-01-01

    Research is being conducted by Oak Ridge National Laboratory under US nuclear regulatory commission (USNRC) sponsorship to address aging management of nuclear power plant containment and other safety-related structures. Documentation is being prepared to provide the USNRC with potential structural safety issues and acceptance criteria for use in continued service evaluations of nuclear power plants. Accomplishments include development of a structural materials information center containing data and information on the time variation of 144 material properties under the influence of pertinent environmental stressors or aging factors, evaluation of models for potential concrete containment degradation factors, development of a procedure to identify critical structures and degradation factors important to aging management, evaluations of non-destructive evaluation techniques, assessments of European and North American repair practices for concrete, review of parameters affecting corrosion of metals embedded in concrete, and development of methodologies for making current condition assessments and service life predictions of new or existing reinforced concrete structures in nuclear power plants. (orig.)

  18. Aging management of containment structures in nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.

    1994-01-01

    Research is being conducted by Oak Ridge National Laboratory under U.S. Nuclear Regulatory Commission sponsorship to address aging management of nuclear power plant containment and other safety-related structures. Documentation is being prepared to provide the US-NRC with potential structural safety issues and acceptance criteria for use in continued service evaluations of nuclear power plants. Accomplishments include development of a Structural Materials Information Center containing data and information on the time variation of 144 material properties under the influence of pertinent environmental stressors or aging factors, evaluation of models for potential concrete containment degradation factors, development of a procedure to identify critical structures and degradation factors important to aging management, evaluations of nondestructive evaluation techniques, assessments of European and North American repair practices for concrete, review of parameters affecting corrosion of metals embedded in concrete, and development of methodologies for making current condition assessments and service life predictions of new or existing reinforced concrete structures in nuclear power plants. (author). 29 refs., 2 figs

  19. Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, N. [RIKEN, Wako, iTHES Research Group, Saitama (Japan); Far Eastern Federal University, Complex Simulation Group, School of Biomedicine, Vladivostok (Russian Federation); Sahoo, B.K. [Physical Research Laboratory, Atomic, Molecular and Optical Physics Division, Ahmedabad (India); Yoshinaga, N. [Graduate School of Science and Engineering, Saitama (Japan); Sato, T. [RIKEN, Nishina Center, Saitama (Japan); Asahi, K. [RIKEN, Nishina Center, Saitama (Japan); Tokyo Institute of Technology, Department of Physics and International Education and Research Center of Science, Tokyo (Japan); Das, B.P. [Tokyo Institute of Technology, Department of Physics and International Education and Research Center of Science, Tokyo (Japan)

    2017-03-15

    The current status of electric dipole moments of diamagnetic atoms which involves the synergy between atomic experiments and three different theoretical areas, i.e. particle, nuclear and atomic, is reviewed. Various models of particle physics that predict CP violation, which is necessary for the existence of such electric dipole moments, are presented. These include the standard model of particle physics and various extensions of it. Effective hadron level combined charge conjugation (C) and parity (P) symmetry violating interactions are derived taking into consideration different ways in which a nucleon interacts with other nucleons as well as with electrons. Nuclear structure calculations of the CP-odd nuclear Schiff moment are discussed using the shell model and other theoretical approaches. Results of the calculations of atomic electric dipole moments due to the interaction of the nuclear Schiff moment with the electrons and the P and time-reversal (T) symmetry violating tensor-pseudotensor electron-nucleus are elucidated using different relativistic many-body theories. The principles of the measurement of the electric dipole moments of diamagnetic atoms are outlined. Upper limits for the nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained combining the results of atomic experiments and relativistic many-body theories. The coefficients for the different sources of CP violation have been estimated at the elementary particle level for all the diamagnetic atoms of current experimental interest and their implications for physics beyond the standard model is discussed. Possible improvements of the current results of the measurements as well as quantum chromodynamics, nuclear and atomic calculations are suggested. (orig.)

  20. Nuclear structure at high and very high spin theoretical description

    International Nuclear Information System (INIS)

    Szymanski, Z.

    1983-11-01

    When the existence of nuclear shell structure is ignored and nuclear motion is assumed to be classical we may expect that the nuclear rotation resembles that of a liquid drop. Energy of the nucleus can be thus considered as a sum of three terms: surface energy, Coulomb energy and rotational energy. Nuclear moment of inertia is assumed to be that of a rigid-body. The results of a calculation of the energy surfaces in rotating nuclei by Cohen, Plasil and Swiatecki are discussed. Cranking procedure is analysed as a tool to investigate nucleonic orbits in a rotating nuclear potential. Some predictions concerning the possible onset of a superdeformed phase are given. The structure of nuclear rotation is examined in the presence of the short-range pairing forces that generate the superfluid correlations in the nucleus. Examples of the Bengtsson-Frauendorf plots (quasiparticle energies versus angular velocity of rotation) are given and discussed. The backbending phenomenon is analysed in terms of band crossing. The dependence of the crossing frequency on the pairing-force strength is discussed. Possibilities of the role of new components in the two-body force (quadrupole-pairing) are considered. Possibilities of the phase transition from superfluid to normal states in the nucleus are analysed. The role of the second (dynamic) moment of inertia I(2) in this analysis is discussed. In spherical weekly deformed nuclei (mostly oblate) angular momentum is aligned parallel to the nuclear symmetry axis. Rotation is of non collective origin in this case. Examples of the analysis of nuclear spectra in this case (exhibiting also the isomeric states called yrast (traps)) are given. Possible forms of the collective excitations superimposed on top of the high-spin states are discussed. In particular, the giant resonance excitations formed on top of the high-spin states are considered and their properties discussed

  1. Status of the SPES project, a new tool for fundamental and apply science studies with exotic ion beams at LNL

    Energy Technology Data Exchange (ETDEWEB)

    Napoli, D. R., E-mail: napoli@lnl.infn.it; Andrighetto, A.; Antonini, P.; Benini, D.; Bermudez, J.; Bisoffi, G.; Boratto, E.; Bortolato, D.; Calderolla, M.; Calore, A.; Campo, D.; Carturan, S.; Cinausero, M.; Comunian, M.; Corradetti, S.; De Angelis, G.; De Ruvo, P. L.; Esposito, J.; Ferrari, L.; Galatá, A. [INFN - Laboratori Nazionali di Legnaro, Viale dell’Università 2, I-35020 Legnaro (PD) (Italy); and others

    2016-07-07

    SPES, a new accelerator facility for both the production of exotic ion beams and radio-pharmaceuticals, is presently being installed at the Laboratori Nazionali di Legnaro in Italy (LNL). The new cyclotron, which will provide high intensity proton beams for the production of the rare isotopes, has been installed and is now in the commissioning phase. We present here the status of the part of the project devoted to the production and acceleration of fission fragments created in the interaction of an intense proton beam on a production target of UCx. The expected SPES radioactive beams intensities, their quality and their maximum energies (up to 11 MeV/A for A=130) will permit to perform forefront research in nuclear structure and nuclear dynamics far from the stability valley. Another low energy section of the facility is foreseen for new and challenging research, both in the nuclear physics and in the material science frameworks.

  2. Nuclear fuel assembly incorporating primary and secondary structural support members

    International Nuclear Information System (INIS)

    Carlson, W.R.; Gjertsen, R.K.; Miller, J.V.

    1987-01-01

    A nuclear fuel assembly, comprising: (a) an upper end structure; (b) a lower end structure; (c) elongated primary structural members extending longitudinally between and rigidly interconnecting the upper and lower end structures, the upper and lower end structures and primary structural members together forming a rigid structural skeleton of the fuel assembly; (d) transverse grids supported on the primary structural members at axially spaced locations therealong between the upper and lower end structures; (e) fuel rods extending through and supported by the grids between the upper and lower end structures so as to extend in generally side-by-side spaced relation to one another and to the primary structural members; and (f) elongated secondary structural members extending longitudinally between but unconnected with the upper and lower end structures, the secondary structural members extending through and rigidly interconnected with the grids to extend in generally side-by-side spaced relation to one another, to the fuel rods and to the primary structural members so as to bolster the stiffness of the structural skeleton of the fuel assembly

  3. Nuclear structure from radioactive decay: Annual progress report

    International Nuclear Information System (INIS)

    Wood, J.L.

    1988-01-01

    The primary focus this year has been the continuing studies of intruder states and shape coexistence in the neutron-deficient Z /approximately/ 82 region. Most notably, an extensive region of odd-mass nuclei is emerging within which low-lying low-energy electric monopole (EO) transitions occur. This is a completely new nuclear structure phenomenon. The empirical results are based on on-line decay scheme spectroscopy of mass-separated isotopes at UNISOR. In particular, many transition multipolarities are determined from conversion electron subshell ratios observed in γ-gated electron coincidence spectra. This is a completely new nuclear spectroscopic technique. To cite a specific example: our studies of the 185 Au → 185 Pt decay scheme reveal at least 11 transitions with EO components. This is unprecedented in nuclear structure. The role of EO transitions is being pursued in the larger framework of a signature of shape coexistence in nuclei

  4. Structural design of nuclear power plant using stiffened steel plate concrete structure

    International Nuclear Information System (INIS)

    Moon, Ilhwan; Kim, Sungmin; Mun, Taeyoup; Kim, Keunkyeong; Sun, Wonsang

    2009-01-01

    Nuclear power is an alternative energy source that is conducive to mitigate the environmental strains. The countries having nuclear power plants are encouraging research and development sector to find ways to construct safer and more economically feasible nuclear power plants. Modularization using Steel Plate Concrete(SC) structure has been proposed as a solution to these efforts. A study of structural modules using SC structure has been performed for shortening of construction period and enhancement of structural safety of NPP structures in Korea. As a result of the research, the design code and design techniques based on limit state design method has been developed. The design code has been developed through various structural tests and theoretical studies, and it has been modified by application design of SC structure for NPP buildings. The code consists of unstiffened SC wall design, stiffened SC wall design, Half-SC slab design, stud design, connection design and so on. The stiffened steel plate concrete(SSC) wall is SC structure whose steel plates with ribs are composed on both sides of the concrete wall, and this structure was developed for improved constructability and safety of SC structure. This paper explains a design application of SC structure for a sample building specially devised to reflect all of major structural properties of main buildings of APR1400. In addition, Stiffening effect of SSC structure is evaluated and structural efficiency of SSC structure is verified in comparison with that of unstiffened SC structure. (author)

  5. Condition monitoring and maintenance of nuclear power plant concrete structures

    International Nuclear Information System (INIS)

    Orr, R.; Prasad, N.

    1988-01-01

    Nuclear power plant concrete structures are potentially subject to deterioration due to several environmental conditions, including weather exposure, ground water exposure, and sustained high temperature and radiation levels. The nuclear power plant are generally licensed for a term of 40 years. In order to maximize the return from the existing plants, feasibility studies are in progress for continued operation of many of these plants beyond the original licensed life span. This paper describes a study that was performed with an objective to define appropriate condition monitoring and maintenance procedures. A timely implementation of a condition monitoring and maintenance program would provide a valuable database and would provide justification for extension of the plant's design life. The study included concrete structures such as the containment buildings, interior structures, basemats, intake structures and cooling towers. Age-related deterioration at several operating power plants was surveyed and the potential degradation mechanisms have been identified

  6. Quality assurance in the structural installations of nuclear power stations

    International Nuclear Information System (INIS)

    Schnellenbach, G.; Wrage, S.

    1985-01-01

    The concept of quality assurance distinguishes between self-monitoring of the design, manufacturing and executing firms and external monitoring by state institutions or by experts commissioned by them. The long-term control of structures is within the area of responsibility of the owner. This quality assurance concept is controlled in detail by statutes, which clearly define responsibilities. This structural engineering quality assurance system also forms the basis for the design, construction and utilization of structural installations of nuclear power stations; requirements emanating from the Atomic Energy Acts for the structural installations demand, however, to some extent a sharpening of self- and external monitoring. Therefore, today a quality concept has been developed for the important engineering safety-related buildings of nuclear power stations. This concept takes account of the strict requirements imposed and fulfils the requirement of KTA 1401. (orig.) [de

  7. The role of nuclear shapes in nuclear structure (from the perspective of the Daresbury Tandem)

    International Nuclear Information System (INIS)

    Nazarewicz, W.

    1993-01-01

    In specific regions of the nuclear periodic chart, large multipole moments are observed and the low-lying excitations have a rotational character. These features are understood if the nuclei in question are assumed to have a stable deformation, i.e., a non-spherical distribution of the nuclear matter. In other (transitional) regions the quasi-rotational bands are present; they are strongly coupled to low-lying vibrational modes. Those nuclei are best understood in terms of small static deformations but large dynamic fluctuations around local equilibria. As a matter of fact, the vast majority of nuclei are deformed; even in those which are spherical or almost spherical, the dynamical couplings to shape vibrations are crucial. The issue of nuclear deformation is many-faceted. If the nuclear shape (nuclear mean field) is deformed, characteristic excitation modes are present, such as rotations and vibrations built upon the non-spherical equilibrium. Through the particle-core coupling, nuclear deformations can dramatically influence the single-particle properties of nucleons moving in the average nuclear potential. Many experimental investigations using the Daresbury Tandem were related in one way or another to the physics of nuclear shapes. Fundamental discoveries from Daresbury include the observation of superdeformed structures in rapidly rotating nuclei, the observation of identical (open-quotes twinnedclose quotes) rotational bands, various studies of structural changes induced by very fast rotation (band-crossings, band-terminations), the observation of the oblate-deformed open-quotes dipoleclose quotes bands, studies of reflection-asymmetric shapes, studies of (quasimolecular) cluster configurations in light nuclei, and many, many others. The author reviews the forefront research at Daresbury from the global perspective; the common denominator being the nuclear shape deformation

  8. Towards a novel laser-driven method of exotic nuclei extraction−acceleration for fundamental physics and technology

    Energy Technology Data Exchange (ETDEWEB)

    Nishiuchi, M., E-mail: sergei@jaea.go.jp; Sakaki, H.; Esirkepov, T. Zh. [Japan Atomic Energy Agency, Kansai Photon Science Institute (Japan); Nishio, K. [Japan Atomic Energy Agency, Advanced Science Research Center (Japan); Pikuz, T. A.; Faenov, A. Ya. [Japan Atomic Energy Agency, Kansai Photon Science Institute (Japan); Skobelev, I. Yu. [Russian Academy of Sciences, Joint Institute for High Temperature (Russian Federation); Orlandi, R. [Japan Atomic Energy Agency, Advanced Science Research Center (Japan); Pirozhkov, A. S.; Sagisaka, A.; Ogura, K.; Kanasaki, M.; Kiriyama, H.; Fukuda, Y. [Japan Atomic Energy Agency, Kansai Photon Science Institute (Japan); Koura, H. [Japan Atomic Energy Agency, Advanced Science Research Center (Japan); Kando, M. [Japan Atomic Energy Agency, Kansai Photon Science Institute (Japan); Yamauchi, T. [Graduate School of Maritime Sciences (Japan); Watanabe, Y. [Kyushu University, Interdisciplinary Graduate School of Engineering Sciences (Japan); Bulanov, S. V., E-mail: svbulanov@gmail.com; Kondo, K. [Japan Atomic Energy Agency, Kansai Photon Science Institute (Japan); and others

    2016-04-15

    A combination of a petawatt laser and nuclear physics techniques can crucially facilitate the measurement of exotic nuclei properties. With numerical simulations and laser-driven experiments we show prospects for the Laser-driven Exotic Nuclei extraction–acceleration method proposed in [M. Nishiuchi et al., Phys, Plasmas 22, 033107 (2015)]: a femtosecond petawatt laser, irradiating a target bombarded by an external ion beam, extracts from the target and accelerates to few GeV highly charged short-lived heavy exotic nuclei created in the target via nuclear reactions.

  9. Natural circulating passive cooling system for nuclear reactor containment structure

    Science.gov (United States)

    Gou, Perng-Fei; Wade, Gentry E.

    1990-01-01

    A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

  10. Passive cooling system for nuclear reactor containment structure

    Science.gov (United States)

    Gou, Perng-Fei; Wade, Gentry E.

    1989-01-01

    A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

  11. Structure of nuclear transition matrix elements for neutrinoless ...

    Indian Academy of Sciences (India)

    Abstract. The structure of nuclear transition matrix elements (NTMEs) required for the study of neutrinoless double- decay within light Majorana neutrino mass mechanism is disassembled in the PHFB model. The NTMEs are calculated using a set of HFB intrinsic wave functions, the reliability of which has been previously ...

  12. Detailed requirements for a next generation nuclear data structure.

    Energy Technology Data Exchange (ETDEWEB)

    Brown, D. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-07-05

    This document attempts to compile the requirements for the top-levels of a hierarchical arrangement of nuclear data such as found in the ENDF format. This set of requirements will be used to guide the development of a new data structure to replace the legacy ENDF format.

  13. Structure of nuclear transition matrix elements for neutrinoless ...

    Indian Academy of Sciences (India)

    Abstract. The structure of nuclear transition matrix elements (NTMEs) required for the study of neutrinoless double-β decay within light Majorana neutrino mass mechanism is disassembled in the PHFB model. The NTMEs are calculated using a set of HFB intrinsic wave functions, the reliability of which has been previously ...

  14. Nuclear structure at high angular momentum

    International Nuclear Information System (INIS)

    Stephens, F.S.

    1976-08-01

    There is considerable interest in high angular-momentum states of nuclei, and some recent progress in three areas is discussed. Part I considers transitional nuclei, where two types of rotational bands--decoupled and strongly coupled--are found to occur very frequently. These can be described by several collective models, but the required potential-energy surfaces seem to differ somewhat from those calculated microscopically. In Part II the processes that might cause backbending (irregularities in the rotational levels of certain nuclei) are discussed, and alignment of individual nucleons now seems to be the cause in most cases. The mixing of the ground band with this aligned band can be studied in some detail using Coulomb excitation with very heavy ions. Part III deals with the very high-spin states where effective moments of inertia have been obtained for spins up to 50h. Also structure has been seen in the spectra around these spin values which can be tentatively related to calculated shell effects. 74 references, 61 figures

  15. Structural Health Monitoring of Nuclear Spent Fuel Storage Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lingyu

    2018-04-10

    Interim storage of spent nuclear fuel from reactor sites has gained additional importance and urgency for resolving waste-management-related technical issues. To ensure that nuclear power remains clean energy, monitoring has been identified by DOE as a high priority cross-cutting need, necessary to determine and predict the degradation state of the systems, structures, and components (SSCs) important to safety (ITS). Therefore, nondestructive structural condition monitoring becomes a need to be installed on existing or to be integrated into future storage system to quantify the state of health or to guarantee the safe operation of nuclear power plants (NPPs) during their extended life span. In this project, the lead university and the collaborating national laboratory teamed to develop a nuclear structural health monitoring (n-SHM) system based on in-situ piezoelectric sensing technologies that can monitor structural degradation and aging for nuclear spent fuel DCSS and similar structures. We also aimed to identify and quantify possible influences of nuclear spent fuel environment (temperature and radiation) to the piezoelectric sensor system and come up with adequate solutions and guidelines therefore. We have therefore developed analytical model for piezoelectric based n-SHM methods, with considerations of temperature and irradiation influence on the model of sensing and algorithms in acoustic emission (AE), guided ultrasonic waves (GUW), and electromechanical impedance spectroscopy (EMIS). On the other side, experimentally the temperature and irradiation influence on the piezoelectric sensors and sensing capabilities were investigated. Both short-term and long-term irradiation investigation with our collaborating national laboratory were performed. Moreover, we developed multi-modal sensing, validated in laboratory setup, and conducted the testing on the We performed multi-modal sensing development, verification and validation tests on very complex structures

  16. Engineerig of structural modifications for operating nuclear plants

    International Nuclear Information System (INIS)

    Duffy, T.J.; Gazda, P.A.

    1983-01-01

    The engineering of structural modifications for operating nuclear plants offers many challenges in the areas of scheduling of work, field adjustments, and engineering staff planning. The scheduling of structural modification work for operating nuclear plants is normally closely tied to planned or unplanned outages of the plant. Coordination between the structural engineering effort, the operating plant staff, and the contractor who will be performing the modifications is essential to ensure that all work can be completed within the allotted time. Due to the inaccessibility of areas in operating plants or the short time available to perform the structural engineering in the case of an unscheduled outage, field verification of a design is not always possible prior to initiating the construction of the modification. This requires the structural engineer to work closely with the contractor to promptly resolve problems due to unanticipated interferences or material procurement that may arise during the course of construction. The engineering staff planning for structural modifications at an operating nuclear plant must be flexible enough to permit rapid response to the common 'fire drills', but controlled enough to assure technically correct designs and minimize the expenditure of man-hours and resulting engineering cost. (orig.)

  17. Aging of concrete containment structures in nuclear power plants

    International Nuclear Information System (INIS)

    Naus, D.J.; Oland, C.B.; Ellingwood, B.; Mori, Yasuhiro; Arndt, E.G.

    1992-01-01

    Concrete structures play a vital role in the safe operation of all light-water reactor plants in the US Pertinent concrete structures are described in terms of their importance design, considerations, and materials of construction. Degradation factors which can potentially impact the ability of these structures to meet their functional and performance requirements are identified. Current inservice inspection requirements for concrete containments are summarized. A review of the performance history of the concrete components in nuclear power plants is provided. A summary is presented. A summary is presented of the Structural Aging (SAG) Program being conducted at the Oak Ridge National Laboratory for the US Nuclear Regulatory Commission. The SAG Program is addressing the aging management of safety-related concrete structures in nuclear power plants for the purpose of providing improved bases for their continued service. The program consists of a management task and three technical tasks: materials property data base, structural component assessment/repair technologies, and quantitiative methodology for continued service conditions. Objectives and a summary of accomplishments under each of these tasks are presented

  18. RATU - Nuclear power plant structural safety research programme

    International Nuclear Information System (INIS)

    Rintamaa, R.

    1992-07-01

    Studies on the structural materials in nuclear power plants create the experimental data and background information necessary for the structural integrity assessments of mechanical components. The research is carried out by developing experimental fracture mechanics methods including statistical analysis methods of materials property data, and by studying material ageing and, in particular, mechanisms of material deterioration due to neutron irradiation, corrosion and water chemistry. Besides material studies, new testing methods and sensors for measurement of loading and water chemistry parameters have been developed. The monitoring data obtained in real power plants has been used to simulate more precisely the real environment during laboratory tests. The research on structural analysis has focused on extending and verifying the analysis capabilities for structural assessments of nuclear power plants. A widely applicable system including various computational fracture assessment methods has been created with which different structural problems can be solved reliably and effectively. Research on reliability assessment of maintenance in nuclear power plants is directed to practical case studies on components and structures of safety importance, and to the development of models for maintenance related decision support. A systematic analysis of motor-operated valve has been performed

  19. Exotic Nuclei Arena in JHP

    International Nuclear Information System (INIS)

    Nomura, T.

    1991-12-01

    The Exotic Nuclei Arena planned in Japanese Hadron Project aims to accelerate various unstable nuclei produced in 1-GeV proton-induced reactions up to 6.5 MeV/u by means of heavy-ion linacs. The present status of research and development for the Earena is briefly reported. The construction of the prototype facility to accelerate unstable beams up to 0.8 MeV/u is planned in 1992-94, in which the existing cyclotron in INS is used as the primary accelerator. (author)

  20. Exotic Small Mammals and Bartonella

    Centers for Disease Control (CDC) Podcasts

    2009-04-09

    In this podcast, Dr. Nina Marano discusses Bartonella, a bacterial agent that’s prevalent in many species, including cats, dogs, and cattle. Wild animals are normally thought to carry Bartonella, so when animals are caught in the wild for pet trade, the risk that humans can become infected with Bartonella increases. Bartonella is an identified risk associated with ownership of exotic animals and has serious health consequences.  Created: 4/9/2009 by Emerging Infectious Diseases.   Date Released: 4/9/2009.

  1. Mitigating exotic impacts: restoring native deer mouse populations elevated by an exotic food subsidy

    Science.gov (United States)

    Dean E. Pearson; Robert J. Fletcher

    2008-01-01

    The threat posed by exotic organisms to native systems has led to extensive research on exotic invaders, yet management of invasives has progressed relatively slowly. This is partly due to poor understanding of how exotic species management influences native organisms. To address this shortfall, we experimentally evaluated the efficacy of an invasives management tool...

  2. Mean field based calculations with the Gogny force: Some theoretical tools to explore the nuclear structure

    Energy Technology Data Exchange (ETDEWEB)

    Peru, S. [CEA, DAM, DIF, Arpajon (France); Martini, M. [Ghent University, Department of Physics and Astronomy, Gent (Belgium); CEA, DAM, DIF, Arpajon (France); Universite Libre de Bruxelles, Institut d' Astronomie et d' Astrophysique, CP-226, Brussels (Belgium)

    2014-05-15

    We present a review of several works using the finite-range Gogny interaction in mean field approaches and beyond to explore the most striking nuclear structure features. Shell evolution along the N = 16, 20, 28, 40 isotopic chains is investigated. The static deformation obtained in the mean field description are shown to be often in disagreement with the one experimentally determined. Dynamics is addressed in a GCM-like method, including rotational degrees of freedom, namely the five-dimension collective Hamiltonian (5DCH). This framework allows the description of the low-energy collective excitations. Nevertheless, some data cannot be reproduced with the collective Hamiltonian approach. Thus the QRPA formalism is introduced and used to simultaneously describe high- and low-energy spectroscopy as well as collective and individual excitations. After the description of giant resonances in doubly magic exotic nuclei, the role of the intrinsic deformation in giant resonances is presented. The appearance of low-energy dipole resonances in light nuclei is also discussed. In particular the isoscalar or isovector nature of Pygmy states is debated. Then, the first microscopic fully coherent description of the multipole spectrum of heavy deformed nucleus {sup 238}U is presented. Finally, a comparison of the low-energy spectrum obtained within the two extensions of the static mean field, namely QRPA and 5DCH, is performed for 2{sup +} states in N = 16 isotones, nickel and tin isotopes. For the first time the different static and dynamic factors involved in the generation of the 2{sup +} states in the nickel isotopic chain, from drip line to drip line, can be analysed in only one set of coherent approaches, free of adjustable parameters, using the same two-body interaction D1S and the resulting HFB mean field. (orig.)

  3. Investigations of nuclear structure and nuclear reactions induced by complex projectiles

    International Nuclear Information System (INIS)

    Sarantites, D.G.

    1992-01-01

    The research program described touches five areas of nuclear physics: nuclear structure studies at high spin (hyperdeformation in the mass A ≅ 182 region, structure of 182 Hg and 182 Au at high spin, a highly deformed band in 136 Pm and the anomalous h 11/2 proton crossing in the A∼135 superdeformed region), studies at the interface between structure and reactions (population of entry states in heavy-ion fusion reactions, nuclear structure effects in proton evaporation spectra, nuclear structure- dependent entry state population by total spectroscopy, entrance channel effects in fusion near the barrier, lifetimes of subbarrier α particles by the atomic clock method), production and study of hot nuclei (the statistical model evaporation code EVAP, statistical emission of deuterons and tritons from highly excited compound nuclei, heavy-fragment emission as a probe of the thermal properties of highly excited compound nuclei, use of incoming-wave boundary condition transmission coefficients in the statistical model: implications in the particle evaporation spectra, study of transparency in the optical model), reaction mechanism studies (binary character of highly dissipative 209 Bi + 136 Xe collisions at E/A=28.2 MeV), and development and use of novel techniques and instrumentation in these areas of research (including a 4π channel selection device, a novel x-ray detector, and a simple channel-selecting detector)

  4. Is nuclear structure relevant to non-mesonic hyper-nuclear weak decay?

    International Nuclear Information System (INIS)

    Wu, H.C.; Ponce, W.A.

    2001-01-01

    Full text: The focus of existing studies of the non-mesonic hypernuclear weak decay has been on the two-body process ΛN → NN, whereas the investigation on effects of nuclear structure is relatively rare. Some authors even assumed that the nuclear structure is irrelevant to the non mesonic hypernuclear weak decay. In this work we try to reveal the importance of nuclear structure in non mesonic weak decay of the Λ - hypernuclei through examining the relevance of many-body properties as well as the single particle properties of different nuclear models. For hypernucleus 12 Λ C, a comparison between the L-S coupling (realized by the symmetry model SU(4) x SU(3) and the j-j coupling (realized by the single particle shell model) gives an estimate of the range of nuclear structure effects. It has been found that while the total decay rate is almost independent of coupling schemes, the ratio Γn/Γp has a difference of around 30% between the two limits of many-body wave functions. There also exists a strong dependence of the total decay rate and the ratio Γn/Γp on the single particle properties of shell model, such as the binding energy of nucleon and the parameters of harmonic oscillator orbits, etc. Therefore, one may conclude that the nuclear structure is relevant to the non-mesonic hypernuclear weak decay. With the mechanism of ΛN → NN transition being restricted to one pion exchange (OPE) only, the consequences of possible contribution from the ΔI = 3/2 channel is investigated in a phenomenological manner. It has been shown that a mixing of ΔI = 3/2 channel will change the total decay rate as well as the ratio Γn/Γp considerably. (Author)

  5. The ISOL exotic beam facility at LNS: the EXCYT project

    International Nuclear Information System (INIS)

    Ciavola, G.; Calabretta, L.; Cuttone, G.; Di Bartolo, G.; Finocchiaro, P.; Gammino, S.; Gu, M.; Migneco, E.; Raia, G.; Rifuggiato, D.; Rovelli, A.; Vinciguerra, D.; Qin, J.; Wollnik, H.

    1997-01-01

    The aim of the EXCYT project (exotics with cyclotron and tandem) is the development of a facility for producing and accelerating exotic beams from 0.2 up to 8 MeV/amu. EXCYT is based on the ''two accelerators'' method. A K=800 superconducting cyclotron, axially injected by the ECR ion source SERSE, will deliver the primary beam. Such a beam will produce the required nuclear species in a modified ISOLDE type target-source complex. When required, a 15 MV tandem Van der Graaff will accelerate the secondary beams. Both accelerators are existing and operational at Laboratorio Nazionale del Sud. Concerning the status of the project, progress has been made in most of the key issues of the project, like the construction of SERSE, cyclotron upgrading, modification of the existing building, high resolution mass separator, and diagnostic equipment for low energy, low intensity beams. (orig.)

  6. The ISOL exotic beam facility at LNS: the EXCYT project

    Energy Technology Data Exchange (ETDEWEB)

    Ciavola, G.; Calabretta, L.; Cuttone, G.; Di Bartolo, G.; Finocchiaro, P.; Gammino, S.; Gu, M.; Migneco, E.; Raia, G.; Rifuggiato, D.; Rovelli, A.; Vinciguerra, D. [Istituto Nazionale di Fisica Nucleare, Catania (Italy); Qin, J. [Institute of Atomic Energy, Beijing (China); Wollnik, H. [Giessen Univ. (Germany)

    1997-04-01

    The aim of the EXCYT project (exotics with cyclotron and tandem) is the development of a facility for producing and accelerating exotic beams from 0.2 up to 8 MeV/amu. EXCYT is based on the ``two accelerators`` method. A K=800 superconducting cyclotron, axially injected by the ECR ion source SERSE, will deliver the primary beam. Such a beam will produce the required nuclear species in a modified ISOLDE type target-source complex. When required, a 15 MV tandem Van der Graaff will accelerate the secondary beams. Both accelerators are existing and operational at Laboratorio Nazionale del Sud. Concerning the status of the project, progress has been made in most of the key issues of the project, like the construction of SERSE, cyclotron upgrading, modification of the existing building, high resolution mass separator, and diagnostic equipment for low energy, low intensity beams. (orig.). 8 refs.

  7. Microstructural characterization and pore structure analysis of nuclear graphite

    International Nuclear Information System (INIS)

    Kane, J.; Karthik, C.; Butt, D.P.; Windes, W.E.; Ubic, R.

    2011-01-01

    Graphite will be used as a structural and moderator material in next-generation nuclear reactors. While the overall nature of the production of nuclear graphite is well understood, the historic nuclear grades of graphite are no longer available. This paper reports the virgin microstructural characteristics of filler particles and macro-scale porosity in virgin nuclear graphite grades of interest to the Next Generation Nuclear Plant program. Optical microscopy was used to characterize filler particle size and shape as well as the arrangement of shrinkage cracks. Computer aided image analysis was applied to optical images to quantitatively determine the variation of pore structure, area, eccentricity, and orientation within and between grades. The overall porosity ranged between ∼14% and 21%. A few large pores constitute the majority of the overall porosity. The distribution of pore area in all grades was roughly logarithmic in nature. The average pore was best fit by an ellipse with aspect ratio of ∼2. An estimated 0.6-0.9% of observed porosity was attributed to shrinkage cracks in the filler particles. Finally, a preferred orientation of the porosity was observed in all grades.

  8. Nuclear structure studies of rare francium isotopes using Collinear Resonance Ionization Spectroscopy (CRIS)

    CERN Document Server

    AUTHOR|(CDS)2084441

    It was known for many years that nuclei possessing certain numbers of protons (Z) and neutrons (N), called the magic numbers (8,20,28,50,82,126...), exhibit characteristic behavior and are in general more stable than their neighboring isotopes. As the capabilities of producing isotopes with more extreme values of Z and N increased, it was realized that those spherical nuclei only represent a small fraction of the total number of isotopes and that most isotopes are deformed. In order to study exotic isotopes and their deformation, it was necessary to develop new experimental techniques that would be powerful enough to be able to cope with very small production yields, but precise enough to measure the nuclear properties (such as radii and moments) with relatively small uncertainties. One technique that can measure nuclear properties of scarcely produced isotopes is in-source resonant ionization, but this technique does not allow for sufficient precision to deduce nuclear quadrupole moments. Furthermore, this t...

  9. Beta decay and structure of exotic nuclei in the mass regions N=Z, A {approx} 70 and near the N=20 closed shell

    Energy Technology Data Exchange (ETDEWEB)

    Courtin, S.; Baumann, P.; Dessagne, Ph.; Marechal, F.; Miehe, Ch.; Perrot, F.; Poirier, E.; Ramdhane, M. [Institut de Recherches Subatomiques, Strasbourg Cedex 2 (France); ISOLDE collaboration

    2004-09-15

    This paper describes two beta decay experiments performed at the CERN/ISOLDE mass separator. The structure of {sup 74}Kr has been studied using a total absorption {gamma} spectrometer (TAgS). The measured Gamow-Teller strength is presented and compared to HFBCS+QRPA calculations. The {sup 33}Na decay is also presented. The structure of the {sup 33}Mg daughter nucleus is compared to shell-model calculations, showing for the first time an inversion of states in the A{sub {approx}}35 mass region. (author)

  10. The exotic exchange of smoke rings

    International Nuclear Information System (INIS)

    Niemi, Antti J.

    2006-01-01

    Smoke rings are fascinating, to humans and animals alike. Experienced cigarette smokers blow them for entertainment while dolphins play with air-filled underwater rings that know how to puff. Smoke ring machines can be bought from science gadget shops and Lord Kelvin explains in a paper [Lord Kelvin, Proceedings of the Royal Society of Edinburgh, Vol. VI (1867), p. 94; reprinted in Philos. Mag. Vol. XXXIV (1867), p. 15] how one can be constructed from a cardboard box. Even Mount Etna [http://news.bbc.co.uk/1/hi/sci/tech/696953.stm] and our Sun [http://spacescience.com/headlines/y2000/ast03feb 1 .htm] are known to be sources of huge smoke rings. But a smoke ring is not only fun to watch. It is also an organized structure with the ability to engage in complex acts, best exemplified by the leapfrogging motion of two smoke rings. Here we propose that the leapfrogging actually encodes very important Physics: It is a direct three dimensional generalization of the motion that in the two dimensional context is responsible for exotic exchange statistics which rules the properties of structures and materials such as quantum Hall systems and high-temperature superconductors. By employing very simple and universal concepts with roots in the hydrodynamical Euler equation, the universal law that describes the properties of fluids and gases, we argue that three dimensional exotic exchange statistics is commonplace. Our observations could have far reaching consequences in fluids and gases which are subject to the laws of quantum mechanics, from helium superfluids to Bose-Einstein condensed alkali gases and even metallic hydrogen in its liquid phases. (author)

  11. Search for low mass exotic baryons in one pion electroproduction data measured at JLAB

    International Nuclear Information System (INIS)

    Tatischeff, B.; Tomasi-Gustafsson, E.

    2007-02-01

    This paper aims to give further evidence for the existence of low mass exotic baryons. Narrow structures in baryonic missing mass or baryonic invariant mass were previously observed during the last ten years. Since their existence is sometimes questionable, the structure functions of one pion electroproduction cross sections, measured at JLAB, are studied to add information on the possible existence of these narrow exotic baryonic resonances. (authors)

  12. Theoretical study of elastic electron scattering off stable and exotic nuclei

    International Nuclear Information System (INIS)

    Roca-Maza, X.; Centelles, M.; Salvat, F.; Vinas, X.

    2008-01-01

    Results for elastic electron scattering by nuclei, calculated with charge densities of Skyrme forces and covariant effective Lagrangians that accurately describe nuclear ground states, are compared against experiment in stable isotopes. Dirac partial-wave calculations are performed with an adapted version of the ELSEPA package. Motivated by the fact that studies of electron scattering off exotic nuclei are intended in future facilities in the commissioned GSI and RIKEN upgrades, we survey the theoretical predictions from neutron-deficient to neutron-rich isotopes in the tin and calcium isotopic chains. The charge densities of a covariant interaction that describes the low-energy electromagnetic structure of the nucleon within the Lagrangian of the theory are used to this end. The study is restricted to medium- and heavy-mass nuclei because the charge densities are computed in mean-field approach. Because the experimental analysis of scattering data commonly involves parameterized charge densities, as a surrogate exercise for the yet unexplored exotic nuclei, we fit our calculated mean-field densities with Helm model distributions. This procedure turns out to be helpful to study the neutron-number variation of the scattering observables and allows us to identify correlations of potential interest among some of these observables within the isotopic chains

  13. Exotic Options: a Chooser Option and its Pricing

    Directory of Open Access Journals (Sweden)

    Raimonda Martinkutė-Kaulienė

    2012-12-01

    Full Text Available Financial instruments traded in the markets and investors’ situation in such markets are getting more and more complex. This leads to more complex derivative structures used for hedging that are harder to analyze and which risk is harder managed. Because of the complexity of these instruments, the basic characteristics of many exotic options may sometimes be not clearly understood. Most scientific studies have been focused on developing models for pricing various types of exotic options, but it is important to study their unique characteristics and to understand them correctly in order to use them in proper market situations. The paper examines main aspects of options, emphasizing the variety of exotic options and their place in financial markets and risk management process. As the exact valuation of exotic options is quite difficult, the article deals with the theoretical and practical aspects of pricing of chooser options that suggest a broad range of usage and application in different market conditions. The calculations made in the article showed that the price of the chooser is closely correlated with the choice time and low correlated with its strike price. So the first mentioned factor should be taken into consideration when making appropriate hedging and investing decisions.

  14. Development of SC structure modularization in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Mun, Taeyoup

    2008-01-01

    New Focus on NPP are Rising Concerns on Global Warming, Potential energy crisis (geo-political), Improved reliability and safety of nuclear power plant, Advent of Generation 3+ NPP technology and Economical Energy Resource. New NPPs are 6 units in Korea and 23 in Asia being built, 32 units being planned in China by 2020 (150 by 2050), 10 units being planned in US by 2020 and IAEA expects $200 billions on NPP construction next 25 years (up to 30% of total world energy). □ SC(Steel Plate Concrete) structure · Steel Plate is used as a Structural Element instead of Reinforcing Bars in RC · SC structure consists of Steel Plate with Headed Studs. Connected by Tie-bars - The Primary Purpose of Tie-bars is to Stiffen and Hold Together the Plates during Construction Process - Headed Studs are Welded to the Inside of Steel Plate for composite action □ Benefits of SC Structure · Shorten Construction Duration for Re bar, Forming and Scaffolding Works · Minimize Site Labors · Improve the Construction Quality · Enable Construction Sites to be kept Clean □ SC Modularization · Fit for Modular Construction for Structural Features · Fit for Modular Construction for Structural Features · Inattentively Effective for Integrated Modules · Pre-fabrication, Pre-assembly and Modularization □ Project Overview · Project Name: Development of SC structure for Modularization in NPP · Project Type: Electric Power Industry R and D (Ministry of Knowledge Economy) · Duration: Sep. 2005 ∼ Aug. 2008 (36 Months) · Research Team and Scopes - Project Management: Korea Hydro and Nuclear Power Company (KHNP) - Development of Code and Standards for SC Structure: Korea Society of Steel Construction (KSSC) Korea Electric Power Research Institute (KEPRI) - Development of SC Structural Analysis and Design: Korea Power Engineering Company (KOPEC) - Development of Construction Techniques for SC Modularization: KHNP, Korea Institute of Nuclear Safety(KINS), KOPEC □ Performance

  15. Beyond habitat structure: Landscape heterogeneity explains the monito del monte (Dromiciops gliroides) occurrence and behavior at habitats dominated by exotic trees.

    Science.gov (United States)

    Salazar, Daniela A; Fontúrbel, Francisco E

    2016-09-01

    Habitat structure determines species occurrence and behavior. However, human activities are altering natural habitat structure, potentially hampering native species due to the loss of nesting cavities, shelter or movement pathways. The South American temperate rainforest is experiencing an accelerated loss and degradation, compromising the persistence of many native species, and particularly of the monito del monte (Dromiciops gliroides Thomas, 1894), an arboreal marsupial that plays a key role as seed disperser. Aiming to compare 2 contrasting habitats (a native forest and a transformed habitat composed of abandoned Eucalyptus plantations and native understory vegetation), we assessed D. gliroides' occurrence using camera traps and measured several structural features (e.g. shrub and bamboo cover, deadwood presence, moss abundance) at 100 camera locations. Complementarily, we used radio telemetry to assess its spatial ecology, aiming to depict a more complete scenario. Moss abundance was the only significant variable explaining D. gliroides occurrence between habitats, and no structural variable explained its occurrence at the transformed habitat. There were no differences in home range, core area or inter-individual overlapping. In the transformed habitats, tracked individuals used native and Eucalyptus-associated vegetation types according to their abundance. Diurnal locations (and, hence, nesting sites) were located exclusively in native vegetation. The landscape heterogeneity resulting from the vicinity of native and Eucalyptus-associated vegetation likely explains D. gliroides occurrence better than the habitat structure itself, as it may be use Eucalyptus-associated vegetation for feeding purposes but depend on native vegetation for nesting. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  16. John Huizenga at the Nuclear Structure Research Lab. (NSRL)

    International Nuclear Information System (INIS)

    Gove, H.E.

    1986-01-01

    The first experiments at the University of Rochester's Nuclear Structure Research Laboratory were carried out in early November of 1966 and the accelerator itself was officially accepted in April of 1967. The laboratory's inception was a result of an idea of Robert Marshack and Bruce French of the Department of Physics and Astronomy at Rochester. A proposal was submitted to three federal agencies in February 1962. The proposal was accepted by the latter organization, the National Science Foundation and NSRL has flourished in nuclear science since that time. This paper presents an overview of John Huizenga's activities at the NSRL

  17. Structural change of Japan's nuclear R and D organization

    International Nuclear Information System (INIS)

    Yoon, S. W.; Jeong, H. S.; Lee, T. Z.

    2002-01-01

    Recently Japanese government is performing a reform work in order to solve the problem involved the existing Special Public Institutions. As results to, JAERI and JNC will be merged into a new independent administrative institution which will be expected to Japan's nuclear policy effectively. Henceforth, government of Japan will establish the legislation and organizational structure until 2005. From the finding of this case study, we should make an effort in order to carry out Korea's nuclear R and D effectively for the strengthening of national competitive

  18. Considerations about soil-structures interaction in nuclear power plants

    International Nuclear Information System (INIS)

    Muzzi, F.

    1977-01-01

    The main features of the soil-structure interaction for nuclear power plant are presented as they resulted from conservations that the author carried out at the Berkeley (California) University, at the California Institute of Technology and at the U.S. Nuclear Regulatory Commission in Washington (Dec 1975). The complete and inertial interaction approaches of analysis are discussed. The complete approach by the use of finite element technique as suggested by the U.S.N.R.C. Standard Review Plan 3.7.1. (June 1975) is finally described. (author)

  19. NUCLEAR STRUCTURE AND DECAY DATA: INTRODUCTION TO RELEVANT WEB PAGES

    International Nuclear Information System (INIS)

    BURROWS, T.W.; MCLAUGHLIN, P.D.; NICHOLS, A.L.

    2005-01-01

    A brief description is given of the nuclear data centres around the world able to provide access to those databases and programs of highest relevance to nuclear structure and decay data specialists. A number of Web-page addresses are also provided for the reader to inspect and investigate these data and codes for study, evaluation and calculation. These instructions are not meant to be comprehensive, but should provide the reader with a reasonable means of electronic access to the most important data sets and programs

  20. Nuclear Structure Studies with Gamma-Ray Beams

    Directory of Open Access Journals (Sweden)

    Tonchev Anton

    2015-01-01

    Full Text Available In stable and weakly bound neutron-rich nuclei, a resonance-like concentration of dipole states has been observed for excitation energies below the neutron-separation energy. This clustering of strong dipole states has been named the Pygmy Dipole Resonance (PDR in contrast to the Giant Dipole Resonance (GDR that dominates the E1 response. Understanding the PDR is presently of great interest in nuclear structure and nuclear astrophysics. High-sensitivity studies of E1 and M1 transitions in closed-shell nuclei using monoenergetic and 100% linearly-polarized photon beams are presented.