Theoretical spectroscopic studies of the atomic transitions and lifetimes of low-lying states in Ti IV

International Nuclear Information System (INIS)

Mandal, Subhasish; Dixit, Gopal; Majumder, Sonjoy; Sahoo, B K; Chaudhuri, R K

2008-01-01

The astrophysically important electric quadrupole (E2) and magnetic dipole (M1) transitions for the low-lying states of triply ionized titanium (Ti IV) are calculated very accurately using a state-of-the-art all-order many-body theory called coupled cluster (CC) method in the relativistic framework. Different many-body correlations of the CC theory has been estimated by studying the core and valence electron excitations to the unoccupied states. The calculated excitation energies of different states are in excellent agreement with the measurements. Also, we compare our calculated electric dipole (E1) amplitudes of few transitions with recent many-body calculations by others. The lifetimes of the low-lying states of Ti IV have been estimated and long lifetime is found for the first excited 3d 2 D 5/2 state, which suggested that Ti IV may be one of the useful candidates for many fundamental studies of physics. Most of the forbidden transition results reported here are not available in the literature, to the best of our knowledge

Low-lying qq(qq)-bar states in a relativistic model based on the Bethe-Salpeter equation

International Nuclear Information System (INIS)

Ram, B.; Kriss, V.

1985-01-01

Low-lying qq(qq)-bar states are analysed in a previously given relativistic model based on the Bethe-Salpeter equation. It is not got M-diquonia, P-mesonia, or meson molecules, but it is got T-diquonia

Identification of low-lying proton-based intruder states in 189-193Pb

International Nuclear Information System (INIS)

Vel, K. van de; Andreyev, A.N.; Huyse, M.; Duppen, P. van; Cocks, J.F.C.; Dorvaux, O.; Greenlees, P.T.; Helariutta, K.; Jones, P.; Julin, R.; Juutinen, S.; Kettunen, H.; Kuusiniemi, P.; Leino, M.; Muikku, M.; Nieminen, P.; Eskola, K.; Wyss, R.

2002-01-01

Low-lying proton-based intruder states have been observed in the odd-mass isotopes 189,191,193 Pb in experiments at the RITU gas-filled recoil separator. The identification has been performed by observing the fine structure in the α decay of the parent 193,195,197 Po nuclei in prompt coincidence with conversion electrons and γ rays in the daughter lead isotopes. Along with the literature data these results establish a systematics of intruder states in the odd-mass lead isotopes from 197 Pb down to 185 Pb. Interpretation of these states involves the coupling of the 1i 13/2 or 3p 3/2 odd neutron to the 0 + state in the oblate minimum in the even-mass lead core. Conversion coefficients have been determined for some of the transitions, revealing mixing between the coexisting states. The experimental results are compared to potential energy surface calculations

Calculations of energy levels and lifetimes of low-lying states of barium and radium

International Nuclear Information System (INIS)

Dzuba, V. A.; Ginges, J. S. M.

2006-01-01

We use the configuration-interaction method and many-body perturbation theory to perform accurate calculations of energy levels, transition amplitudes, and lifetimes of low-lying states of barium and radium. Calculations for radium are needed for the planning of measurements of parity- and time-invariance-violating effects which are strongly enhanced in this atom. Calculations for barium are used to control the accuracy of the calculations

Deep-lying hole states in the optical model

International Nuclear Information System (INIS)

Klevansky, S.P.; Lemmer, R.H.

1982-01-01

The strength function for deep-lying hole states in an optical potential is studied by the method of Green's functions. The role of isospin is emphasized. It is shown that, while the main trends of the experimental data on hole states in isotopes of Sn and Pd can be described by an energy independent optical potential, intermediate structures in these data indicate the specific nuclear polarization effects have to be included. This is done by introducing doorway states of good isospin into the optical model potential. Such states consist of neutron hole plus proton core vibrations as well as more complicated excitations that are analog states of proton hole plus neutron core vibrations of the parent nuclear system. Specific calculations for 115 Sn and 103 Pd give satisfactory fits to the strength function data using optical model and doorway state parameters that are reasonable on physical grounds

Decay modes of high-lying single-particle states in [sup 209]Pb

Energy Technology Data Exchange (ETDEWEB)

Beaumel, D.; Fortier, S.; Gales, S.; Guillot, J.; Langevin-Joliot, H.; Laurent, H.; Maison, J.M.; Vernotte, J.; Bordewijk, J.A.; Brandenburg, S.; Krasznahorkay, A.; Crawley, G.M.; Massolo, C.P.; Renteria, M. (Institut de Physique Nucleaire, Institut National de Physique Nucleaire et de Physique des Particules Centre National de la Recherche Scientifique, 91406 Orsay Cedex (France) Kernfysisch Versneller Instituut, 9747AA Groningen (Netherlands) National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States) Departamento de Fisica, Fac. Cs. Exactas, Universidad Nacional de La Plata, CC No. 67, 1900 La Plata (Argentina))

1994-05-01

The neutron decay of high-lying single-particle states in [sup 209]Pb excited by means of the ([alpha],[sup 3]He) reaction has been investigated at 122 MeV incident energy using a multidetector array. The high spin values of these states, inferred from previous inclusive experiments, are confirmed by the present data involving angular correlation measurements and the determination of branching ratios to low lying levels in [sup 208]Pb. The structure located between 8.5 and 12 MeV excitation energy in [sup 209]Pb displays large departures from a pure statistical decay with significant direct feeding of the low-lying collective states (3[sup [minus

Description of low-lying vibrational Kπ≠0+ states of deformed nuclei in the quasiparticle-phonon nuclear model

International Nuclear Information System (INIS)

Soloviev, V.G.; Shirikova, N.Yu.

1989-01-01

The QPNM equations are derived taking account of p-h and p-p interactions. The calculated quadrupole, octupole and hexadecapole vibrational states in 168 Er, 172 Yb and 178 Hf are found to be in reasonable agreement with experimental data. It is shown that distribution of the Eλ strength in some deformed nuclei differs from the standard one. There are cases when for a given K π the Eλ strength is concentrated not on the first but on higher-lying states. The assertion made earlier about the absence of collective two-phonon states in deformed nuclei is confirmed. (orig.)

Description of low-lying vibrational Kπ ≠ 0+ states of deformed nuclei in the quasiparticle-phonon nuclear model

International Nuclear Information System (INIS)

Solov'ev, V.G.; Shirikova, N.Yu.

1989-01-01

The QPNM equations are derived taking account of p-h and p-p interactions. The calculated quadrupole, octupole and hexadecapole vibrational states in 168 Er, 172 Yb and 178 Hf are found to be reasonale agreement with experimental data. It is shown that distribution of the Eλ strength in some deformed nuclei differs from the standard one. There are cases when for a given K π and Eλ strength is concentrated not on the first but on higher-lying states. The assertion made earlier about the absence of collective two-phonon states in deformed nuclei is confirmed. 44 refs.; 1 fig.; 6 tabs

Decay modes of high-lying single-particle states in 209Pb

International Nuclear Information System (INIS)

Beaumel, D.; Fortier, S.; Gales, S.; Guillot, J.; Crawley, G.M.; Massolo, C.P.; Renteria, M.

1993-01-01

The neutron decay of high-lying single-particle states in 209 Pb excited by means of the (α, 3 He) reaction has been investigated at 122 MeV incident energy using the multidetector array EDEN. The high spin values of these states, inferred from previous inclusive experiments, are confirmed by the present data involving angular correlation measurements and the determination of branching ratios to low lying levels in 208 Pb. The structure located between 8.5 and 12 MeV excitation energy in 209 Pb displays large departures from a pure statistical decay with significant direct feeding of the low-lying collective states (3 - ,5 - ) of 208 Pb. At higher excitation energy up to 20 MeV, the measured neutron decay is in agreement with the predictions of the statistical model. (authors). 24 refs., 16 figs., 2 tabs

The low-lying electronic states of pentacene and their roles in singlet fission.

Science.gov (United States)

Zeng, Tao; Hoffmann, Roald; Ananth, Nandini

2014-04-16

We present a detailed study of pentacene monomer and dimer that serves to reconcile extant views of its singlet fission. We obtain the correct ordering of singlet excited-state energy levels in a pentacene molecule (E (S1) pentacene, we use a well-developed diabatization scheme to characterize the six low-lying singlet states of a pentacene dimer that approximates the unit cell structure of crystalline pentacene. The local, single-excitonic diabats are not directly coupled with the important multiexcitonic state but rather mix through their mutual couplings with one of the charge-transfer configurations. We analyze the mixing of diabats as a function of monomer separation and pentacene rotation. By defining an oscillator strength measure of the coherent population of the multiexcitonic diabat, essential to singlet fission, we find this population can, in principle, be increased by small compression along a specific crystal direction.

Damping mechanisms of high-lying single-particle states in 91Nb

International Nuclear Information System (INIS)

Molen, H. K. T. van der; Berg, A. M. van den; Harakeh, M. N.; Hunyadi, M.; Kalantar-Nayestanaki, N.; Akimune, H.; Daito, I.; Fujimura, H.; Ihara, F.; Inomata, T.; Ishibashi, K.; Yoshida, H.; Yosoi, M.; Fujita, Y.; Fujiwara, M.; Jaenecke, J.; O'Donnell, T. W.; Laurent, H.; Lhenry, I.; Rodin, V. A.

2007-01-01

Decay by proton emission from high-lying states in 91 Nb, populated in the 90 Zr(α,t) reaction at E α =180 MeV, has been investigated. Decay to the ground state and semidirect decay to the low-lying (2 + ,5 - , and 3 - ) phonon states in 90 Zr were observed. It was found that these phonon states play an important role in the damping process of the single-particle states. An optical-model coupled-channel approach was used successfully to describe the direct and semidirect parts of the decay

Present status of the microscopic study of low-lying collective states in spherical and transitional nuclei

International Nuclear Information System (INIS)

Marumori, Toshio; Takada, Kenjiro; Sakata, Fumihiko.

1981-12-01

The history and the present status of the microscopic study of the low-lying collective excited states in spherical and transitional nuclei are discussed by putting emphasis on explaining the rather modern microscopic investigations of the concept of collective subspace. Importance of the dynamical interplay between the pairing and the quadrupole correlations is emphasized as a crucial element to mediate coupling between the collective and non-collective subspace. (author)

A density matrix renormalization group study of low-lying excitations ...

Indian Academy of Sciences (India)

Symmetrized density-matrix-renormalization-group calculations have been carried out, within Pariser-Parr-Pople Hamiltonian, to explore the nature of the ground and low-lying excited states of long polythiophene oligomers. We have exploited 2 symmetry and spin parity of the system to obtain excited states of ...

The structure of nuclear states at low, intermediate and high excitation energies

International Nuclear Information System (INIS)

Soloviev, V.G.

1976-01-01

It is shown that within the model based on the quasiparticle-phonon interaction one can obtain the description of few-quasiparticle components of nuclear states at low, intermediate and high excitation energies. For the low-lying states the energy of each level is calculated. The few-quasiparticle components at intermediate and high excitation energies are represented to be averaged in certain energy intervals and their characteri stics are given as the corresponding strength functions. The fragmentation of single-particle states in deformed nuclei is studied. It is shown that in the distribution of the single-particle strength alongside with a large maximum there appear local maxima and the distribution itself has a long tail. The dependence of neutron strength functions on the excitation energy is investigated for the transfer reaction of the type (d,p) and (d,t). The s,- p,- and d-wave neutron strength functions are calculated at the neutron binding energy Bn. A satisfactory agreement with experiment is obtained. The energies and Elambda-strength functions for giant multipole resonances in deformed nuclei are calculated. The energies of giant quadrupole and octupole resonances are calculated. Their widths and fine structure are being studied. It is stated that to study the structure of highly excited states it is necessary to find the values of many-quasiparticle components of the wave functions. The ways of experimental determination of these components based on the study of γ-transitions between highly excited states are discussed

Charge transfer and relativistic effects in the low-lying electronic states of CuCl, CuBr and CuI

NARCIS (Netherlands)

Sousa, C; de Jong, W.A.; Broer, R.; Nieuwpoort, WC

1997-01-01

The spectral transitions and the character of the low-lying excited states of the copper halides, CuX (X = Cl, Br, I) are studied by means of two different relativistic computational approaches. One is based on the CASSCF/CASPT2 approach with operators accounting for scalar relativistic effects

Low-lying nuclear levels and radiative transitions in hadronic atoms

International Nuclear Information System (INIS)

Popov, V.S.; Kudryavtsev, A.E.; Lisin, V.I.; Mur, V.D.

1985-01-01

The analytic theory of nuclear level shifts permit the position of the nuclear level perturbing the Coulomb spectrum to be calculated on the basis of the magnitude of the level shift of a hadron atom. As an example the K -4 He atom is discussed. The experimental data on the 2p-level shift indicate that a weakly bound p-state with a binding energy and width epsilon approximately γ approximately 0.5 MeV may exist in the system. The probabilities for radiative transitions to this level and the cross section for its creation in a nuclear reaction with 6 Li are calculated. The possible existence of weakly coupled K - and anti p states for other light nuclei is discussed. An exact solution of the model Coulomb problem with short range interaction is obtained and this permits the limits of validity of the initial approximations to be determined

The Electro-Excitation Form Factors for Low-Lying States of 7Li Nucleus

International Nuclear Information System (INIS)

Dakhl, Z.A.; Salih, L.; Al-Qazaz, B.S.

2010-01-01

The transverse electron scattering form factors have been studied for low -lying excited states of 7 L i nucleus. These states are specified by JπT= (0.478MeV),(4.63MeV) and(6.68MeV). The transitions to these states are taking place by both isoscalar and isovector components. These form factors have been analyzed in the framework of the multi-nucleon configuration mixing of harmonic oscillator shell model with size parameter b r ms=1.74fm. The universal two-body of Cohen-Kurath is used to generate the 1p-shell wave functions. The core polarization effects are included in the calculations through effective g-factors and resolved many discrepancies with experiments. A higher configuration effect outside the 1p-shell model space, such as the 2p-shell, enhances the form factors for q-values and reproduces the data. The present results are compared with other theoretical models. PACS: 25.30.Bf Elastic electron scattering - 25.30.Dh Inelastic electron scattering to specific states - 21.60.Cs Shell model - 27.20. +n 5≤ A ≥19

Low-level nuclear waste in Washington State

International Nuclear Information System (INIS)

Williams, H.

1986-01-01

A commercial disposal site for low-level nuclear wastes opened at Hanford in 1965. By 1971 a total of six were in operation: Hanford, Nevada, South Carolina, Kentucky, New York State, and Illinois. The history of the operation of these sites is described. Only the first three listed are still open. The effects of the large volumes of waste expected from Three Mile Island are described. This paper examines the case history of Hanford operations with low-level waste disposal for lessons that might apply in other states being considered for disposal sites

Structure and bonding of ScCN and ScNC: Ground and low-lying states

International Nuclear Information System (INIS)

Kalemos, Apostolos; Metropoulos, Aristophanes; Mavridis, Aristides

2012-01-01

Graphical abstract: The experimentally unknown systems ScCN and ScNC have been studied through single reference CISD and CCSD(T) methods. A total of 20 = 10 (ScCN) + 10 (ScNC) states were examined. All states are quite ionic whereas ScNC(X ∼3 Δ) is stabler than ScCN(X ∼3 Δ) by ∼5 kcal/mol. Display Omitted Highlights: ► We have studied through ab initio methods the polytopic system Sc[CN]. ► A series of low lying states for both isomeric forms have been examined. ► Around equilibrium the system displays a pronounced Sc + [CN] − ionic character. - Abstract: We have studied the experimentally unknown Sc[CN] molecular system in both its isomeric forms, scandium cyanide (ScCN) and isocyanide (ScNC), through ab initio computations. We report energetics, geometries, harmonic frequencies, and dipole moments for the first 20 Sc[CN] states correlating diabatically to Sc + ( 3 D, 1 D, 3 F) + CN − (X 1 Σ + ). Both isomers have a pronounced ionic character around equilibrium due to the high electron affinity of the CN group and the low ionization energy of the Sc atom. According to our calculations the ScNC isomer (X ∼3 Δ) is stabler than the ScCN(X ∼3 Δ) by ∼5 kcal/mol.

Low-lying dipole strength of the open-shell nucleus 94Mo

Science.gov (United States)

Romig, C.; Beller, J.; Glorius, J.; Isaak, J.; Kelley, J. H.; Kwan, E.; Pietralla, N.; Ponomarev, V. Yu.; Sauerwein, A.; Savran, D.; Scheck, M.; Schnorrenberger, L.; Sonnabend, K.; Tonchev, A. P.; Tornow, W.; Weller, H. R.; Zilges, A.; Zweidinger, M.

2013-10-01

The low-lying dipole strength of the open-shell nucleus 94Mo was studied via the nuclear resonance fluorescence technique up to 8.7 MeV excitation energy at the bremsstrahlung facility at the Superconducting Darmstadt Electron Linear Accelerator (S-DALINAC), and with Compton backscattered photons at the High Intensity γ-ray Source (HIγS) facility. In total, 83 excited states were identified. Exploiting polarized quasi-monoenergetic photons at HIγS, parity quantum numbers were assigned to 41 states excited by dipole transitions. The electric dipole-strength distribution was determined up to 8.7 MeV and compared to microscopic calculations within the quasiparticle phonon model. Calculations and experimental data are in good agreement for the fragmentation, as well as for the integrated strength. The average decay pattern of the excited states was investigated exploiting the HIγS measurements at five energy settings. Mean branching ratios to the ground state and first excited 21+ state were extracted from the measurements with quasi-monoenergetic photons and compared to γ-cascade simulations within the statistical model. The experimentally deduced mean branching ratios exhibit a resonance-like maximum at 6.4 MeV which cannot be reproduced within the statistical model. This indicates a nonstatistical structure in the energy range between 5.5 and 7.5 MeV.

Role of quasiparticle x phonon components in gamma-decay of hogh-lying states

International Nuclear Information System (INIS)

Ponomarev, V.Yu.; Solov'ev, V.G.; Vdovin, A.I.; Stoyanov, Ch.

1986-01-01

In the framework of quasiparticle-phonon model of a nucleus the probabilities of gamma-transitions (E1, M1, E2) from a high-lying resonance-similar structure to the excitation of neutron hole state (lg 9/2 ) -1 of 111 Sn nucleus to the main and low-excited one-quasiparticle states have been calculated. Wave function of a highly excited state comprised the components ''quasiparticle x phonon'' and ''quasiparticle x two phonons''. For E1-transitions 9/2 + → 11/2 1 - the main contribution to the transition is made by one-quasiparticle components of wave functions of the initial and final states. E2-transition 9/2 + → 7/2 g,s + takes place at the expense of impurities in ''quasiparticle x phonon'' states. For M1-transition from the states 9/2 + to the main one a strong destructive interference of contributions of one-quasiparticle and ''quasiparticle x phonon'' components is observed. Thus it is shown that components ''quasiparticle x phonon'' may play the major role in correct description of gamma-transitions from high-lying one-particle or low-lying hole states

Theoretical study of the low-lying electronic states of magnesium sulfide cation including spin-orbit interaction

Science.gov (United States)

Chen, Peng; Wang, Ning; Li, Song; Chen, Shan-Jun

2017-11-01

Highly correlated ab initio calculations have been performed for an accurate determination of electronic structures and spectroscopic features for the low-lying electronic states of the MgS+ cation. The potential energy curves for the four Λ-S states correlating to the lowest dissociation asymptote are studied for the first time. Four Λ-S states split into nine Ω states through the spin-orbit coupling effect. Accurate spectroscopic constants are deduced for all bound states. The spin-orbit couplings and the transition dipole moments, as well as the PECs, are utilized to calculate Franck-Condon factors and radiative lifetimes of the vibrational levels. To verify our computational accuracy, analogous calculations for the ground state of MgS are also carried out, and our derived results are in reasonable agreement with available experimental data. In addition, photoelectron spectrum of MgS has been simulated. The predictive results are anticipated to serve as guidelines for further researches such as assisting laboratorial detections and analyzing observed spectrum.

Semirelativistic potential model for low-lying three-gluon glueballs

International Nuclear Information System (INIS)

Mathieu, Vincent; Semay, Claude; Silvestre-Brac, Bernard

2006-01-01

The three-gluon glueball states are studied with the generalization of a semirelativistic potential model giving good results for two-gluon glueballs. The Hamiltonian depends only on 3 parameters fixed on two-gluon glueball spectra: the strong coupling constant, the string tension, and a gluon size which removes singularities in the potential. The Casimir scaling determines the structure of the confinement. Low-lying J PC states are computed and compared with recent lattice calculations. A good agreement is found for 1 -- and 3 -- states, but our model predicts a 2 -- state much higher in energy than the lattice result. The 0 -+ mass is also computed

Low temperature nuclear orientation studies of nuclei far from stability

International Nuclear Information System (INIS)

Brown, D.E.

1990-01-01

One of the major current interests in nuclear physics is to study transitional nuclei which lie between well known regions of spherical and deformed nuclei. The neutron deficient Tellurium and Iodine isotopes are examples of such nuclei. In both cases, the influence of a πg 9/2 intruder orbital is expected to be strong at low excitation energies and at A ∼120. The 120 Te decay scheme has been investigated in detail by LTNO supported by γ-γ coincidences and conversion electron spectroscopy. An interaction of the level scheme using an IBM-2 calculation which allows for mixing between the ground state and a (4p-2h) intruder state is made. The success of this calculation provides strong evidence for the existence of the intruder configuration in 120 Te. In addition, the relative electric quadrupole moments of the ground states in 120-123 I have been measured. The light Platinum isotopes are also transitional nuclei. The ground state magnetic dipole and electric quadrupole moments have been measured for 185,187 Pt which lie inside the region in which the shape transition is known to occur. An interpretation of nuclear moments and level structures in the range 179≤A≤193 using a particle plus triaxial core shows that the shape change takes place gradually via a broad region in which the nuclear shape is triaxial. (author)

Properties of the low-lying levels of 122Sb

International Nuclear Information System (INIS)

Gunsteren, W.F. van; Rabenstein, D.

1977-01-01

Nanosecond lifetimes of low-lying levels in the doubly odd nucleus 122 Sb have been measured. On the basis of these results and of already published experimental material, spins and parities for most of the low-lying states are proposed. A simple theoretical description of this nucleus is presented. The model used is that of a proton coupled to a number projected neutron quasiparticle wave function, assuming a Z=N=50 core. The spectrum and transition rates were calculated in a shell model space consisting of eight subshells and using a renormalized Schiffer interaction. The shell model parameters were derived from adjadent nuclei. Good agreement with the experimental level scheme is found. Also the gamma decay properties can be accounted for rather well. Spectroscopic factors for the one-neutron transfer reactions leading to 122 Sb are predicted. Their measurement with high resolution techniques would be a helpful test for the interpretations given. (orig.) [de

Low-dimensional filiform Lie algebras over finite fields

OpenAIRE

Falcón Ganfornina, Óscar Jesús; Núñez Valdés, Juan; Pacheco Martínez, Ana María; Villar Liñán, María Trinidad; Vasek, Vladimir (Coordinador); Shmaliy, Yuriy S. (Coordinador); Trcek, Denis (Coordinador); Kobayashi, Nobuhiko P. (Coordinador); Choras, Ryszard S. (Coordinador); Klos, Zbigniew (Coordinador)

2011-01-01

In this paper we use some objects of Graph Theory to classify low-dimensional filiform Lie algebras over finite fields. The idea lies in the representation of each Lie algebra by a certain type of graphs. Then, some properties on Graph Theory make easier to classify the algebras. As results, which can be applied in several branches of Physics or Engineering, for instance, we find out that there exist, up to isomorphism, six 6-dimensional filiform Lie algebras over Z/pZ, for p = 2, 3, 5. Pl...

USING MAGNETIC MOMENTS TO UNVEIL THE NUCLEAR STRUCTURE OF LOW-SPIN NUCLEAR STATES

Directory of Open Access Journals (Sweden)

Diego A. Torres

2011-07-01

Full Text Available The experimental study of magnetic moments for nuclear states near the ground state, I ≤ 2, provides a powerful tool to test nuclear structure models. Traditionally, the use of Coulomb excitation reactions has been used to study low spin states, mostly I = 2. The use of alternative reaction channels, such as α transfer, for the production of radioactive species that, otherwise, will be only produced in future radioactive beam facilities has proved to be an alternative to measure not only excited states with I > 2, but to populate and study long-live radioactive nuclei. This contribution will present the experimental tools and challenges for the use of the transient field technique for the measurement of g factors in nuclear states with I ≤ 2, using Coulomb excitation and α-transfer reactions. Recent examples of experimental results near the N = 50 shell closure, and the experimental challenges for future implementations with radioactive beams, will be discussed.

Spectroscopic study of low-lying 16N levels

International Nuclear Information System (INIS)

Bardayan, Daniel W.; O'Malley, Patrick; Blackmon, Jeff C.; Chae, K.Y.; Chipps, K.; Cizewski, J.A.; Hatarik, Robert; Jones, K.L.; Kozub, R. L.; Matei, Catalin; Moazen, Brian; Nesaraja, Caroline D.; Pain, Steven D.; Paulauskas, Stanley; Peters, W.A.; Pittman, S.T.; Schmitt, Kyle; Shriner, J.F. Jr.; Smith, Michael Scott

2008-01-01

The magnitude of the 15N(n,gamma)16N reaction rate in asymptotic giant branch stars depends directly on the neutron spectroscopic factors of low-lying 16N levels. A new study of the 15N(d,p)16N reaction is reported populating the ground and first three excited states in 16N. The measured spectroscopic factors are near unity as expected from shell model calculations, resolving a long-standing discrepancy with earlier measurements that had never been confirmed or understood. Updated 15N(n,gamma)16N reaction rates are presented

Extracting Low-Lying Lambda Resonances Using Correlation Matrix Techniques

International Nuclear Information System (INIS)

Menadue, Benjamin J.; Kamleh, Waseem; Leinweber, Derek B.; Mahbub, M. S.

2011-01-01

The lowest-lying negative-parity state of the Lambda is investigated in (2+1)-flavour full-QCD on the PACS-CS configurations made available through the ILDG. We show that a variational analysis using multiple source and sink smearings can extract a state lying lower than that obtained by using a standard fixed smeared source and sink operator alone.

Inelastic light scattering by low-lying excitations of electrons in low-dimensional semiconductors

Energy Technology Data Exchange (ETDEWEB)

Pellegrini, V. [NEST CNR-INFM and Scuola Normale Superiore, Pisa (Italy); Pinczuk, A. [Department of Physics, Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey (United States)

2006-11-15

The low-dimensional electron systems that reside in artificial semiconductor heterostructures of great perfection are a contemporary materials base for explorations of collective phenomena. Studies of low-lying elementary excitations by inelastic light scattering offer insights on properties such energetics, interactions and spin magnetization. We review here recent light scattering results obtained from two-dimensional (2D) quantum fluids in semiconductor heterostructures under extreme conditions of low temperature and large magnetic field, where the quantum Hall phases are archetypes of novel behaviors. We also consider recent light scattering experiments that have probed the excitation spectra of few-electron states in semiconductor quantum dots. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Iran's nuclear lies

International Nuclear Information System (INIS)

Dickey, Christopher

2005-01-01

Beyond the antiaircraft gun emplacements and the early-warning radar systems, and shortly before you get to the high concrete walls topped with concertina wire that surround Iran's Bushehr Nuclear Power Plant, there's a large sign announcing that the facility Welcomes guests. Like so much about die Iranian nuclear program, die signals are incongruous, contradictory and more then a little sinister. If Iran is to be believed, then the world has nothing to fear from its nuclear program. The United States, Europe, Israel, Saudi Arabia and other oil producers nearby can rest easy, because the ayatollahs have no plans to threaten the region with atomic weapons or put nukes in the hands of terrorists. If Iran is to be believed, its only goal, repeated countless times, ratified in treaties and open to inspections, is to develop a completely independent ability to make nuclear ir fuel and use it to generate electricity. But neither die United States nor Eu rope nor the United Nations is ready simply to believe Iran, at least not easily, and not without verification. Its record of concealment and deceit about its nuclear program goes back at least 20 years. Its extensive uranium-enrichment program was uncovered in detail only two years ago; its promise of 'full disclosure' and 'transparency' since then has been something considerably less. The election of a new hard-line Iranian president, Mahmoud Ahmadinejad, last month raises still more questions about how far Tehran can be trusted about its nuclear programs, if at all. Iran's concealments have been as vast as a secret underground facility at Natanz that was being readied for 50,000 centrifuges to enrich uranium when it was exposed in 2002. They have seemed as small as some undeclared milligrams of plutonium from a research laboratory. In a cat-and-mouse game reminiscent of the lead-up to the Iraq invasion in 2003, the Iranians have claimed to be cooperating while throwing up what often seem to be petty obstacles in front

Dielectronic recombination into excited levels of Ne-like titanium from F-like low-lying states

International Nuclear Information System (INIS)

Qiu Yanghui; Li Shichang; Sun Yongsheng

1993-01-01

The energy levels, wavelengths, oscillator strengths, Auger rates and level-to-level dielectronic recombination rate coefficients describing dielectronic recombination into excited levels of Ne-like titanium from F-like low-lying states are calculated. Our calculations are based on Dr. R.D. Cowan's semi-relativistic mass-velocity and Darwin corrections are included in the Hamiltonian, and the distorted-wave model is used for the calculation of free electron wavefunctions. In order to set the recombination rate coefficients on a level by level basis, in a manner compatible with detailed level population kinetics modelling of highly-stripped ions in plasma, the dielectronic recombination rate coefficients as a function of free electron temperatures are given in an analytical form, which is not only very convenient in practice, but also hopefully accurate compared with the exactly calculated numerical results. (orig.)

Experimental study of the low-lying structure of 94Zr with the (n,n'γ) reaction

International Nuclear Information System (INIS)

Elhami, E.; Orce, J. N.; Scheck, M.; Mukhopadhyay, S.; Choudry, S. N.; McEllistrem, M. T.; Yates, S. W.; Angell, C.; Boswell, M.; Karwowski, H. J.; Fallin, B.; Howell, C. R.; Hutcheson, A.; Parpottas, Y.; Tonchev, A. P.; Tornow, W.; Kelley, J. H.

2008-01-01

The low-lying structure of 40 94 Zr was studied with the (n,n ' γ) reaction, and a level scheme was established based on excitation function and γγ coincidence measurements. Branching ratios, multipole mixing ratios, and spin assignments were determined from angular distribution measurements. Lifetimes of levels up to 3.4 MeV were measured by the Doppler-shift attenuation method, and for many transitions the reduced transition probabilities were determined. In addition to the anomalous 2 2 + state, which has a larger B(E2;2 2 + →0 1 + ) value than the B(E2;2 1 + →0 1 + ), the experimental results revealed interesting and unusual properties of the low-lying states in 94 Zr. In a simple interpretation, the excited states are classified in two distinct categories, i.e., those populating the 2 2 + state and those decaying to the 2 1 + state

Low-lying levels of 129Xe and 131Xe

International Nuclear Information System (INIS)

Palmer, D.C.; Irving, A.D.; Forsyth, P.D.; Hall, I.; Martin, D.G.E.; Maynard, M.J.

1978-01-01

The nuclei 129 Xe and 131 Xe have been studied by Coulomb excitation and by (α, n) reactions on 126 Te and 128 Te. Eleven new levels for 129 Xe and six for 131 Xe and B(E2) transition values for some of the low-lying states are reported. The present Coulomb excitation experiments together with published β-decay work enable some spin-parity assignments and restrictions to be made. The data are broadly consistent with the predictions of the particle-vibrator coupling model, although a thorough comparison requires further spectroscopic measurements and more detailed theoretical calculation. (author)

Deep-hole and high-lying particle states in heavy nuclei

International Nuclear Information System (INIS)

Gales, S.

1985-01-01

Our present knowledge on single-particle strength functions from one nucleon transfer reactions is reviewed. Results on deeply-bound neutron hole states in the Sn and Pb region are discussed with emphasis on the investigation of a very large excitation energy range. The first measurements on the γ-decay of deeply-bound hole states in the Sn isotopes are reported. High energy neutron and proton stripping reactions are used to study the particle response function. These reactions are particularly well suited to the study of high-spin outer subshells. For the proton states, the behaviour of the 1h 11/2 and 1i 13/2 strength distributions, as a function of deformation in the Sm region, is discussed. Strong transitions to high-lying neutron states are observed in the 112, 116, 118, 120, 122, 124 Sn and 208 Pb nuclei. The empirical systematics for both proton and neutron particle strength distributions are compared to the predictions from the quasi particle-phonon and the single-particle vibration coupling nuclear models. (orig.)

Low lying magnetic dipole strength distribution in 176Hf

International Nuclear Information System (INIS)

Kuliev, A. A.; Ertugral, F.; Yakut, H.; Bektasoglu, M.; Guliyev, E.

2006-01-01

In this study the scissors mode 1 + states are systematically investigated within the rotational invariant Quasiparticle Random Phase Approximation (QRPA) for 1 76Hf isotopes. We consider the 1 + vibrations generated by the isovector spin-spin interactions and the isoscalar (h 0 ) and isovector (h 1 ) quadrupole type separable forces restoring the broken symmetry by a deformed mean field. It has been shown that restoration of the broken rotational symmetry of the Hamiltonian essentially decreases the B(M1) value of the low lying 1 + states and increases the collectivization of the scissors mode excitations in the spectroscopic energy region. Agreement between the calculated mean excitation energies as well as the summed B(M1) value of the scissors mode excitations and the available experimental data of 1 76Hf is rather good. For instance, distributions of the calculated B(M1) transition strengths in the 1 76 Hf isotopes with respect to K π =1 + excitations is represented in Figure. Thus, we see that the models which use the Hamiltonian with broken rotational symmetry strongly overestimate the M1 strength at low energy. These results indicate an importance of the models which are free from the low-energy spurious states. The marked differences between the results for 1 + states, calculated in rotational invariant (RI) and non-rotational invariant (NRI) model indicate the importance of the approaches which are free from spurious low-energy solutions. A separation of the rotational state from the 1 + states changes somewhat the distribution of the B(M1) strength in the spectroscopic energy region and increases the fragmentation of the scissors mode 1 + excitations in agreement with the experimental data

Ab initio calculation on the low-lying excited states of Si2+ cation including spin–orbit coupling

International Nuclear Information System (INIS)

Liu, Yanlei; Zhai, Hongsheng; Zhang, Xiaomei; Liu, Yufang

2013-01-01

Highlights: • 24 Λ–S states are correlated to the dissociation limit of Si( 3 P g ) + Si + ( 2 P u ) are first reported. • The dissociation energies of the calculated electronic states are predicted in our work. • It is first time that the entire 54 Ω states generated from the 24 Λ–S states have been studied. • PECs of Λ–S and Ω states are depicted with the aid of avoided crossing rule between the same symmetry. - Abstract: Ab initio all-electron relativistic calculations of the low-lying excited states of Si 2 + have been performed at MRCI+Q/AVQZ level. The calculated electronic states, including 12 doublet and 12 quartet Λ–S states, are correlated to the dissociation limit of Si( 3 P g ) + Si + ( 2 P u ). Spin–orbit interaction is taken into account via the state interaction approach with the full Breit-Pauli Hamiltonian, which causes the entire 24 Λ–S states to split into 54 Ω states. This is the first time that spin–orbit coupling (SOC) calculation has been performed on Si 2 + . The obtained potential energy curves (PECs) of Λ–S and Ω states are respectively depicted with the aid of the avoided crossing rule between the same symmetry. The spectroscopic constants of the bound Λ–S and Ω states are determined, and excellent agreements with the latest theoretical results are achieved

The low-lying πσ* state and its role in the intramolecular charge transfer of aminobenzonitriles and aminobenzethyne

International Nuclear Information System (INIS)

Lee, Jae-Kwang; Fujiwara, Takashige; Kofron, William G.; Zgierski, Marek Z.; Lim, Edward C.

2008-01-01

Electronic absorption spectra of the low-lying ππ* and πσ* states of several aminobenzonitriles and 4-dimethylaminobenzethyne have been studied by time-resolved transient absorption and time-dependent density functional theory calculation. In acetonitrile, the lifetime of the πσ*-state absorption is very short (picoseconds or subpicosecond) for molecules that exhibit intramolecular charge transfer (ICT), and very long (nanoseconds) for those that do not. Where direct comparison of the temporal characteristics of the πσ*-state and the ICT-state transients could be made, the formation rate of the ICT state is identical to the decay rate of the πσ* state within the experimental uncertainty. These results are consistent with the πσ*-mediated ICT mechanism, L a (ππ*)→πσ*→ICT, in which the decay rate of the πσ* state is determined by the rate of the solvent-controlled πσ*→ICT charge-shift reaction. The ππ*→πσ* state crossing does not occur in 3-dimethylaminobenzonitrile or 2-dimethylaminobenzonitrile, as predicted by the calculation, and 4-aminobenzonitrile and 4-dimethylaminobenzethyne does not exhibit the ICT reaction, consistent with the higher energy of the ICT state relative to the πσ* state

Low-lying intruder state of the unbound nucleus {sup 13}Be

Energy Technology Data Exchange (ETDEWEB)

Kondo, Y., E-mail: kondo@phys.titech.ac.j [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Nakamura, T.; Satou, Y. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Matsumoto, T.; Aoi, N. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Endo, N. [Department of Physics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Fukuda, N.; Gomi, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hashimoto, Y. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Ishihara, M. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawai, S. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); Kitayama, M.; Kobayashi, T.; Matsuda, Y. [Department of Physics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Matsui, N. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Motobayashi, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Nakabayashi, T.; Okumura, T. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Ong, H.J.; Onishi, T.K. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)

2010-06-21

An experimental study for the unbound nucleus {sup 13}Be has been performed by means of the invariant mass method via the one-neutron removal reaction {sup 1}H({sup 14}Be,{sup 12}Be+n). A resonance has been observed at 0.51(1) MeV in the relative energy (E{sub rel}) spectrum of the {sup 12}Be+n system. The transverse momentum distribution of the {sup 12}Be+n system as well as the resonance width of 0.45(3) MeV gives evidence for the p-wave nature of the resonance. A d-wave resonance has also been observed at 2.39(5) MeV in the E{sub rel} spectrum. The observation of the low-lying p-wave resonance indicates the disappearance of the N=8 magicity in the vicinity of the neutron drip line region.

The low-lying quartet electronic states of group 14 diatomic borides XB (X = C, Si, Ge, Sn, Pb)

Science.gov (United States)

Pontes, Marcelo A. P.; de Oliveira, Marcos H.; Fernandes, Gabriel F. S.; Da Motta Neto, Joaquim D.; Ferrão, Luiz F. A.; Machado, Francisco B. C.

2018-04-01

The present work focuses in the characterization of the low-lying quartet electronic and spin-orbit states of diatomic borides XB, in which X is an element of group 14 (C, Si, Ge, Sn, PB). The wavefunction was obtained at the CASSCF/MRCI level with a quintuple-ζ quality basis set. Scalar relativistic effects were also taken into account. A systematic and comparative analysis of the spectroscopic properties for the title molecular series was carried out, showing that the (1)4Π→X4Σ- transition band is expected to be measurable by emission spectroscopy to the GeB, SnB and PbB molecules, as already observed for the lighter CB and SiB species.

Effective Hamiltonian and low-lying eigenenergy clustering patterns of four-sublattice antiferromagnets

DEFF Research Database (Denmark)

Zhang, N.G.; Henley, C.L.; Rischel, C.

2002-01-01

We study the low-lying eigenenergy clustering patterns of quantum antiferromagnets with p sublattices (in particular p = 4). We treat each sublattice as a large spin, and using second-order degenerate perturbation theory, we derive the effective (biquadratic) Hamiltonian coupling the p large spins....... In order to compare with exact diagonalizations, the Hamiltonian is explicitly written for a finite-size lattice, and it contains information on energies of excited states as well as the ground state. The result is applied to the face-centered-cubic Type-I antiferromagnet of spin 1/2, including second...

Energy relaxation between low lying tunnel split spin-states of the single molecule magnet Ni4

Science.gov (United States)

de Loubens, G.; Chaves-O'Flynn, G. D.; Kent, A. D.; Ramsey, C.; Del Barco, E.; Beedle, C.; Hendrickson, D. N.

2007-03-01

We have developed integrated magnetic sensors to study quantum tunneling of magnetization (QTM) in single molecule magnet (SMMs) single crystals. These sensors incorporate a microstrip resonator (30 GHz) and a micro-Hall effect magnetometer. They have been used to investigate the relaxation rates between the 2 lowest lying tunnel split spin-states of the SMM Ni4 (S=4). EPR spectroscopy at 30 GHz and 0.4 K and concurrent magnetization measurements of several Ni4 single crystals are presented. EPR enables measurement of the energy splitting between the 2 lowest lying superposition states as a function of the longitudinal and transverse fields. The energy relaxation rate is determined in two ways. First, in cw microwave experiments the change in spin-population together with the microwave absorption directly gives the relaxation time from energy conservation in steady-state. Second, direct time-resolved measurements of the magnetization with pulsed microwave radiation have been performed. The relaxation time is found to vary by several orders of magnitude in different crystals, from a few seconds down to smaller than 100 μs. We discuss this and the form of the relaxation found for different crystals and pulse conditions.

Between silence and lie: the nuclear, from reason of State to 'ecological' recycling

International Nuclear Information System (INIS)

Nordmann, Ch.

2009-01-01

In an interview, an engineer, former member of the French CEA (Commissariat a l'Energie Atomique) gives a rather critical point of view on nuclear energy. He recalls the basic physical principles of nuclear energy, explains the interest in uranium enrichment, comments the relationship between the military origin of the use of nuclear energy and its civil use, describes the various risks associated with the different types of nuclear reactor, comments the safety issues and evokes some critics on the EPR by Finnish and British authorities, comments the problem of nuclear wastes and of their reprocessing, the risk of proliferation. He notes that France is so strongly committed in nuclear energy that it seems unacceptable to criticize it (as he does). Notably, he notes that energy consumption forecast made in the 1970's at the time a massive plant construction plan has been defined, was very much overestimated. Besides, the decision process involves professionals and institutions who transform this decision into a reason of State

Hyperfine structure of six low-lying fine structure levels of 191Ir and 193Ir and the 191Δs193 hyperfine anomaly

International Nuclear Information System (INIS)

Buettgenbach, S.; Dicke, R.; Gebauer, H.; Kuhnen, R.; Traeber, F.

1978-01-01

The hyperfine interaction constants A and B of six low-lying metastable fine structure states of the two iridium isotopes 191 Ir and 193 Ir and the electronic g-factors of these levels have been measured using the atomic-beam magnetic-resonance method. From the values of the magnetic-dipole interaction constants A, corrected for off-diagonal perturbations, we extracted the hyperfine anomaly of a pure 6s-electron state: 191 Δs 193 = 0.64(7)%. Using nonrelativistic approximations for the effective radial parameters the nuclear electric-quadrupole moments were obtained: Q( 191 Ir) = 0.81(21)b, Q( 193 Ir) = 0.73(19)b (corrected for Sternheimer shielding effects). (orig.) [de

Low-lying level structure of the neutron-rich nucleus {sup 109}Nb: A possible oblate-shape isomer

Energy Technology Data Exchange (ETDEWEB)

Watanabe, H., E-mail: hiroshi@ribf.riken.j [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Sumikama, T. [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba (Japan); Nishimura, S. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Yoshinaga, K. [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba (Japan); Li, Z. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Miyashita, Y. [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba (Japan); Yamaguchi, K. [Department of Physics, Osaka University, Machikaneyama-machi 1-1, Osaka 560-0043 Toyonaka (Japan); Baba, H. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Berryman, J.S. [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Blasi, N. [INFN, Sezione di Milano, via Celoria 16, I-20133 Milano (Italy); Bracco, A.; Camera, F. [INFN, Sezione di Milano, via Celoria 16, I-20133 Milano (Italy); Dipartimento di Fisica, Universita di Milano, via Celoria 16, I-20133 Milano (Italy); Chiba, J. [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba (Japan); Doornenbal, P. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Go, S.; Hashimoto, T.; Hayakawa, S. [Center for Nuclear Study, University of Tokyo, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Hinke, C. [Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany); Ideguchi, E. [Center for Nuclear Study, University of Tokyo, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); Isobe, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

2011-01-31

The neutron-rich nuclei {sup 109}Nb and {sup 109}Zr have been populated using in-flight fission of a {sup 238}U beam at 345 MeV/nucleon at the RIBF facility. A T{sub 1/2}=150(30) ns isomer at 313 keV has been identified in {sup 109}Nb for the first time. The low-lying levels in {sup 109}Nb have been also populated following the {beta}-decay of {sup 109}Zr. Based on the difference in feeding pattern between the isomeric and {beta} decays, the decay scheme from the isomeric state in {sup 109}Nb was established. The observed hindrances of the electromagnetic transitions deexciting the isomeric state are discussed in terms of possible shape coexistence. Potential energy surface calculations for single-proton configurations predict the presence of low-lying oblate-deformed states in {sup 109}Nb.

Gyromagnetic ratios of low-lying excited states in the even 192-198Pt isotopes; experimental measurements and theoretical predictions

International Nuclear Information System (INIS)

Stuchbery, A.E.; Ryan, C.G.; Morrison, I.; Bolotin, H.H.

1981-01-01

The gyromagnetic ratios of the 2 2 + and 4 1 + states in 196 Pt were measured relative to that of its 2 1 + level. The thin-foil IMPAC technique was employed utilizing the enhanced transient hyperfine magnetic field present at the nuclei of swiftly recoiling ions traversing magnetized ferromagetic materials. The states of interest were populated by Coulomb excitation using beams of 220-MeV 58 Ni ions. For g(2 1 + ) taken as 0.326+-0.014, the present measurements yielded g(2 2 + ) = 0.30+-0.06 and g(4 1 + ) 0.30+-0.05. These results and those reported by prior workers for the g-factors of corresponding levels in 192 Pt, 194 Pt, 198 Pt are used to trace the systematics of the magnetic moments of these low-lying levels in the even 192 - 198 Pt isotopes. Interacting Boson Approximation model-based calculations of the g-factors of these states were also carried out. The experimental theoretical results are compared

Role of shell structure in the 2νββ nuclear matrix elements

International Nuclear Information System (INIS)

Nakada, H.

1998-01-01

Significance of the nuclear shell structure in the ββ nuclear matrix elements is pointed out. The 2νββ processes are mainly mediated by the low-lying 1 + states. The shell structure also gives rise to concentration or fragmentation of the 2νββ components over intermediate states, depending on nuclide. These roles of the shell structure are numerically confirmed by realistic shell model calculations. Some shell structure effects are suggested for 0νββ matrix elements; dominance of low-lying intermediate states and nucleus-dependence of their spin-parities. (orig.)

Statistical and direct decay of high-lying single-particle excitations

International Nuclear Information System (INIS)

Gales, S.

1993-01-01

Transfer reactions induced by hadronic probes at intermediate energies have revealed a rich spectrum of high-lying excitations embedded in the nuclear continuum. The investigation of their decay properties is believed to be a severe test of their microscopic structure as predicted by microscopic nuclear models. In addition the degree of damping of these simple modes in the nuclear continuum can be obtained by means of the measured particle (n,p) decay branching ratios. The neutron and proton decay studies of high-lying single-particle states in heavy nuclei are presented. (author). 13 refs., 9 figs

Velocity fields and transition densities in nuclear collective modes

Energy Technology Data Exchange (ETDEWEB)

Stringari, S [Dipartimento di Matematica e Fisica, Libera Universita di Trento, Italy

1979-08-13

The shape of the deformations occurring in nuclear collective modes is investigated by means of a microscopic approach. Analytical solutions of the equations of motion are obtained by using simplified nuclear potentials. It is found that the structure of the velocity field and of the transition density of low-lying modes is considerably different from the predictions of irrotational hydrodynamic models. The low-lying octupole state is studied in particular detail by using the Skyrme force.

Low-lying electric-dipole strengths of Ca, Ni, and Sn isotopes imprinted on total reaction cross sections

Science.gov (United States)

Horiuchi, W.; Hatakeyama, S.; Ebata, S.; Suzuki, Y.

2017-08-01

Low-lying electric-dipole (E 1 ) strength of a neutron-rich nucleus contains information on neutron-skin thickness, deformation, and shell evolution. We discuss the possibility of making use of total reaction cross sections on 40Ca, 120Sn, and 208Pb targets to probe the E 1 strength of neutron-rich Ca, Ni, and Sn isotopes. They exhibit large enhancement of the E 1 strength at neutron number N >28 , 50, and 82, respectively, due to a change of the single-particle orbits near the Fermi surface participating in the transitions. The density distributions and the electric-multipole strength functions of those isotopes are calculated by the Hartree-Fock+BCS and the canonical-basis-time-dependent-Hartree-Fock-Bogoliubov methods, respectively, using three kinds of Skyrme-type effective interaction. The nuclear and Coulomb breakup processes are respectively described with the Glauber model and the equivalent photon method in which the effect of finite-charge distribution is taken into account. The three Skyrme interactions give different results for the total reaction cross sections because of different Coulomb breakup contributions. The contribution of the low-lying E 1 strength is amplified when the low-incident energy is chosen. With an appropriate choice of the incident energy and target nucleus, the total reaction cross section can be complementary to the Coulomb excitation for analyzing the low-lying E 1 strength of unstable nuclei.

Comprehensive ab initio calculation and simulation on the low-lying electronic states of TlX (X = F, Cl, Br, I, and At).

Science.gov (United States)

Zou, Wenli; Liu, Wenjian

2009-03-01

The low-lying electronic states of TlX (X=F, Cl, Br, I, and At) are investigated using the configuration interaction based complete active space third-order perturbation theory [CASPT3(CI)] with spin-orbit coupling accounted for. The potential energy curves and the corresponding spectroscopic constants are reported. The results are grossly in good agreement with the available experimental data. The absorption spectra are simulated as well to reassign the experimental bands. The present results are also useful for guiding future experimental measurements.

Low lying states of Th229

DEFF Research Database (Denmark)

Andersen, Torkild; Maack Bisgård, K.; Hansen, P.Gregers

1961-01-01

The decay of 1.6 × 105y U233 has been studied by means of a six gap beta-ray spectrometer, a xenon filled proportional counter and scintillation spectrometers. Internal conversion electrons having energies below 100 keV were measured. The mixing ratios for the 42 keV and the 55 keV transitions ag...... agree with the assumed rotational character of the 42 keV and 97 keV states. Results concerning the 163 keV state indicate that this state is also a member of the ground state rotational band.......The decay of 1.6 × 105y U233 has been studied by means of a six gap beta-ray spectrometer, a xenon filled proportional counter and scintillation spectrometers. Internal conversion electrons having energies below 100 keV were measured. The mixing ratios for the 42 keV and the 55 keV transitions...

Low-lying S-wave and P-wave dibaryons in a nodal structure analysis

International Nuclear Information System (INIS)

Liu Yuxin; Li Jingsheng; Bao Chengguang

2003-01-01

The inherent nodal surface structure analysis approach is proposed for six-quark clusters with u, d, and s quarks. The wave functions of the six-quark clusters are classified, and the contribution of the hidden-color channels are discussed. The quantum numbers and configurations of the wave functions of the low-lying dibaryons are obtained. The states [ΩΩ] (0,0 + ) , [ΩΩ] (0,2 - ) , [Ξ * Ω] (1/2,0 + ) , and [Σ * Σ * ] (0,4 - ) and the hidden-color channel states with the same quantum numbers are proposed to be the candidates of experimentally observable dibaryons

Lifetimes of low-lying excited states in 50 36 86Kr

Science.gov (United States)

Henderson, J.; Chester, A.; Ball, G. C.; Caballero-Folch, R.; Domingo, T.; Drake, T. E.; Evitts, L. J.; Garnsworthy, A. B.; Hackman, G.; Hallam, S.; Moukaddam, M.; Ruotsalainen, P.; Smallcombe, J.; Smith, J. K.; Starosta, K.; Svensson, C. E.; Williams, J.

2018-04-01

Background: The evolution of nuclear magic numbers at extremes of isospin is a topic at the forefront of contemporary nuclear physics. N =50 is a prime example, with increasing experimental data coming to light on potentially doubly magic 100Sn and 78Ni at the proton-rich and proton-deficient extremes, respectively; however, experimental discrepancies exist in the data for less exotic systems. Purpose: In 86Kr the B (E 2 ;21+→01+) value—a key indicator of shell evolution—has been experimentally determined by two different methodologies, with the results deviating by 3 σ . Here, we report on a new high-precision measurement of this value, as well as the first measured lifetimes and hence transition strengths for the 22+ and 3(2) - states in the nucleus. Methods: The Doppler-shift attenuation method was implemented using the TRIUMF-ISAC γ -ray escape-suppressed spectrometer (TIGRESS) γ -ray spectrometer and the TIGRESS integrated plunger device. High-statistics Monte Carlo simulations were utilized to extract lifetimes in accordance with state-of-the-art methodologies. Results: Lifetimes of τ (21+)=336 ±4 (stat.)±20 (sys.) fs, τ (22+)=263 ±9 (stat.)±19 (sys.) fs, and τ (3(2) -)=73 ±6 (stat.)±32 (sys.) fs were extracted. This yields a transition strength for the first-excited state of B (E 2 ;21+→01+)=259 ±3 (stat.)±16 (sys.) e2 fm4. Conclusions: The measured lifetime disagrees with the previous Doppler-shift attenuation method measurement by more than 3 σ , while agreeing well with a previous value extracted from Coulomb excitation. The newly extracted B (E 2 ;21+→01+) value indicates a more significant reduction in the N =50 isotones approaching Z =40 .

Study of the anharmonic effects on low-lying states of odd-mass nuclei in 1g sub(9/2)+ shell region

International Nuclear Information System (INIS)

Nakano, Masahiro

1980-01-01

Anharmonic effects on the low-lying states of the odd-mass nuclei in 1g sub(9/2)sup(+) shell region are investigated by introduction of 1, 3, 5 and 7 quasiparticle modes. Special attention is paid to the energy-lowering of anomalous coupling states in N = 41 nuclei and to the spin sequence of so-called ''one-quasiparticle-two-phonon multiplet''. It is shown that one cannot attribute the special-lowering of the energies of the anomalous coupling (j - 2) states to the dynamical effects due to the coupling between the 3-quasiparticle mode and the 5-quasiparticle mode, and is also shown that not only the kinematical effect but also the dynamical effect plays an important role in the energy-lowering of the anomalous coupling (j - 1) states in N = 41 nuclei. The second (j - 2) state is predicted to be the lowest member of one-quasiparticle-two-phonon multiplet by taking account of the kinematical effect for the 5-quasiparticle mode, which corresponds to the experimental fact. (author)

Study of the β- decay of 116m1In: A new interpretation of low-lying 0+ states in 116Sn

Science.gov (United States)

Pore, J. L.; Cross, D. S.; Andreoiu, C.; Ashley, R.; Ball, G. C.; Bender, P. C.; Chester, A. S.; Diaz Varela, A.; Demand, G. A.; Dunlop, R.; Garnsworthy, A. B.; Garrett, P. E.; Hackman, G.; Hadinia, B.; Jigmeddorj, B.; Laffoley, A. T.; Liblong, A.; Kanungo, R.; Noakes, B.; Petrache, C. M.; Rajabali, M. M.; Starosta, K.; Svensson, C. E.; Voss, P. J.; Wang, Z. M.; Wood, J. L.; Yates, S. W.

2017-02-01

The 116Sn nucleus contains a collective rotational band originating from proton π 2 p-2 h excitations across the proton Z=50 shell gap. Even though this nucleus has been extensively investigated in the past, there was still missing information on the low-energy interband transitions connecting the intruder and normal structures. The low-lying structure of 116Sn was investigated through a high-statistics study of the β- decay of 116m1In with the 8π spectrometer and its ancillary detectors at TRIUMF. These measurements are critical in order to properly characterize the π 2 p-2 h rotational band. Weak γ-decay branches are observed utilizing γ-γ coincidence spectroscopy methods, leading to the first direct observation of the 85 keV 22+→ 03+ γ ray with a transition strength of B(E2) = 99.7(84) W.u. The analysis of these results strongly suggests that the 2027 keV 03+ state should replace the previously assigned 1757 keV 02+ state as the band-head of the π 2 p-2 h rotational band.

Properties of low-lying intruder states in $^{34}$Al and $^{34}$Si sequentially populated in $\\beta$-decay of $^{34}$Mg

CERN Multimedia

A low-lying long-lived (26±1 ms) isomer in $^{34}$Al has been observed recently and assigned as 1$^{+}$ state of intruder character. It was populated in $^{36}$S fragmentation and feeds, in $\\beta$-decay, the 0$_{2}^{+}$ state in $^{34}$Si whose excitation energy and lifetime were determined in an electron-positron pairs spectroscopy experiment. In the present experiment we intend to measure for the first time the $\\gamma$-rays following the $\\beta$-decay of $^{34}$Mg. Despite the interest for $^{34}$Mg, the up-right corner of the “N$\\thicksim$20 island of inversion”, the only information on its $\\beta$-decay is the lifetime of 20±10 ms, determined from $\\beta$-neutron coincidences. As a result of the proposed experiment, we expect to place the first transitions in the level scheme of $^{34}$Al and to strongly populate the newly observed isomer, measuring its excitation energy, if the branching ratio to 4$^{−}$ ground state is significant. Theoretical estimations for the $\\beta$-decay of the new isome...

Deceptive Intentions: Can Cues to Deception Be Measured before a Lie Is Even Stated?

Directory of Open Access Journals (Sweden)

Sabine Ströfer

Full Text Available Can deceitful intentions be discriminated from truthful ones? Previous work consistently demonstrated that deceiving others is accompanied by nervousness/stress and cognitive load. Both are related to increased sympathetic nervous system (SNS activity. We hypothesized that SNS activity already rises during intentions to lie and, consequently, cues to deception can be detected before stating an actual lie. In two experiments, controlling for prospective memory, we monitored SNS activity during lying, truth telling, and truth telling with the aim of lying at a later instance. Electrodermal activity (EDA was used as an indicator of SNS. EDA was highest during lying, and compared to the truth condition, EDA was also raised during the intention to deceive. Moreover, the switch from truth telling toward lying in the intention condition evoked higher EDA than switching toward non-deception related tasks in the lie or truth condition. These results provide first empirical evidence that increased SNS activity related to deception can be monitored before a lie is stated. This implies that cues to deception are already present during the mere intention to lie.

Electroexcitation of Low-Lying Particle-Hole RPA States of 16O with WBP Interaction

International Nuclear Information System (INIS)

Taqi, Ali H.; Radhi, R.A.; Hussein, Adil M.

2014-01-01

The nuclear structure of 16 O is studied in the framework of the particle-hole random phase approximation (ph RPA). The Hamiltonian is diagonalized within a model space with particle orbits {1d 5/2 ,1d 3/2 , and 2s 1/2 } and the hole orbits {1p 3/2 and 1p 1/2 } using Warburton and Brown interaction WBP. The ph RPA calculations are tested, by comparing the electron scattering form factors with the available experimental data. The results of electron scattering form factors and reduced transition strength for the states: 1 − , T = 0 (7.116 MeV); 2 − , T = 1 (12.968 MeV); 2 − , T = 1 (20.412 MeV); and 3 − , T = 0 (6.129 MeV) are interpreted in terms of the harmonic-oscillator (HO) wave functions of size parameter b. The occupation probabilities of the single particle and hole orbits are calculated. The spurious states are removed by adding the center of mass (CM) correction to the nuclear Hamiltonian. A comparison with the available experiments data is presented. (nuclear physics)

Nuclear structure and order-to-chaos transition

International Nuclear Information System (INIS)

Solov'ev, V.G.

1995-01-01

A general scheme of the nuclear many-body problem is presented. Different models for description of low-lying states and giant resonances are discussed. The wave functions of the low-lying states have a single dominating one-quasiparticle or quasiparticle O+ phonon or one-phonon component. They demonstrate the regularity in nuclei. Giant resonances are determined by strongly fragmented one-phonon components of the wave functions. The wave functions at higher excitation energies have two-, three-and many-phonon components. Based on the statement that there is order in the large and chaos in the small components of the nuclear wave functions, the order-to-chaos transition is treated as a transition from the large to the small components of the wave functions. A quasiparticle-phonon interaction is responsible for the fragmentation of one- and many-quasiparticle and phonon states and for the mixing of closely spaced states. Therefore, experimental investigation of the fragmentation of many-quasiparticle and phonon states plays a decisive role. 30 refs

Study of lifetimes of low-lying levels in {sup 53}Mn

Energy Technology Data Exchange (ETDEWEB)

Singh, K.P.; Oswal, Mumtaz; Behera, B.R.; Kumar, Ashok; Singh, Gulzar [Panjab University, Cyclotron Laboratory, Department of Physics, Centre of Advance Study in Physics, Chandigarh (India)

2015-05-15

The properties of low-lying states of {sup 53}Mn were investigated via the {sup 53}Cr(p, n γ){sup 53}Mn reaction using 4.3 MeV proton beam energy. The lifetimes of the levels at 1289.5, 1440.8, 1620.0 and 2273.8 keV excitation energies were measured using the Doppler Shift Attenuation Method (DSAM). The reduced transition probabilities B(M1) and B(E2) were extracted using the measured values of lifetimes for these levels and the mixing ratios from the literature. These values are compared with already known experimental values as well as the shell model calculations using an effective interaction. (orig.)

Low-lying level structure of 73Kr

International Nuclear Information System (INIS)

Moltz, D.M.; Robertson, J.D.; Norman, E.B.; Burde, J.; Beausang, C.W.

1993-01-01

We have used the 40 Ca( 36 Ar, 2pn) reaction to study the low-lying level structure of 73 Kr. By utilizing a bombarding energy at the Coulomb barrier, the relative cross section for this channel was enhanced to a few percent of the total reaction cross section. Levels in 73 Kr were assigned based primarily upon observed neutron-gamma-gamma coincidences and upon comparisons of these newly assigned transition cross sections with those from known nuclei. (orig.)

Coulomb excitations of low lying levels in 127I and 197Au

International Nuclear Information System (INIS)

Singh, K.P.; Tayal, D.C.; Hans, H.S.

1988-01-01

The low-lying levels of 127 I and 197 Au were Coulomb excited with 3.54 to 4.2 MeV protons. The reduced quadrupole transition probabilities of the 203, 374.9, 418, 618.4, 628.7, 651.1 and 745.5 keV states of 127 I, and the 268.8, 278.9, 502, and 547.5 keV states of 197 Au was measured from Coulomb excitation by observing the de-excitation gamma rays with a high resolution Ge(Li) detector. The low-energy protons were used for the first time to Coulomb-excite the two levels at 618.4 and 651.1 keV of 127 I and one level at 502 keV of 197 Au. The present experimental results are found in agreement with the existing experimental data except the B(E2) value of the level at 268.8 keV of 197 Au. (author). 4 figs., 4 tabs., 32 refs

Enhanced spin polarization of elastic electron scattering from alkaline-earth-metal atoms in Ramsauer-Townsend and low-lying shape resonance regions

International Nuclear Information System (INIS)

Yuan, J.; Zhang, Z.

1993-01-01

Spin polarizations (SP's) of elastic electron scattering from alkaline-earth-metal atoms in Ramsauer-Townsend (RT) and low-lying shape resonance (SR) regions are calculated using a relativistic method. The detailed SP distributions both with scattering angle and with electron energy are presented via the energy- and angle-dependent surfaces of SP parameters. It is shown that the SP effects of the collisions of electrons with Ca, Sr, and Ba atoms in the RT region are significant in a considerable area on the energy-angle plane and that the spin-orbit interaction is well increased around the low-lying p-wave SR states of Be and Mg and the d-wave SR states of Ca, Sr, and Ba

State and perspectives of Czechoslovakian nuclear law

International Nuclear Information System (INIS)

Bezdek, R.

1992-01-01

In Czechoslovakia, the peaceful utilization of nuclear energy is governed by a series of legislative norms of varied character and legal power. The most important are the Act No. 194/1988 and the Act No. 28/1984. The former defines the competence of the Czechoslovak Atomic Energy Commission (CAEC), which is the central authority of state administration in the field of utilization of nuclear energy. The latter deals with the State inspection for the nuclear safety of nuclear facilities. In accordance with this Act, the CAEC is the competent authority for the licensing and inspection of nuclear safety. In addition to the two main Acts, a series of CAEC Regulations govern nuclear activities (accounting and control of nuclear materials, radioactive waste management, physical protection, qualifications of personnel in nuclear facilities, quality assurance, etc.). There is no specific legislation governing nuclear third liability. The solution for the various shortcomings of the contemporary codification lies primarily in change of the present codification. This change, however, should not mean a general and indiscriminate ''destruction'' of the legal norms in force at present, but in gradual and purposive creation of an integral, legal system capable of reacting flexibly, the core of which would consist of an Act concerning the peaceful utilization of nuclear energy and on liability for nuclear damage. (author)

An Overlook to Low-Lying 2+ States of Rare Earth Region Nuclei With QRPA Approach

International Nuclear Information System (INIS)

Ganioglu, E.

2008-01-01

As much as known about the nuclear wave function, as much as known about the nuclear structure. Beyond the mean field to get a better wave function it is a way to introduce correlations on top of the mean field solution by means of random phase approximation. Since QRPA is a useful tool for the collective excitations in this study we studied the first 2 + states by means of QRPA and we examine the limits of QRPA description of nuclear excitation in the rare earth region

Low-lying collective quadrupole and octupole strengths in even-even nuclei

International Nuclear Information System (INIS)

Raman, S.; Nestor, C.W. Jr.; Kahane, S.; Bhatt, K.H.

1991-01-01

The B(E2)↑ values for the first 2 + state of even-even nuclei in the Z≥50 region are compared with the predictions of several theoretical models. Comparative estimates of the overall agreement with the data are provided. Gaps and discrepancies in the data and examples that show interesting features such as shape changes are discussed. The B(E2)↑ values are examined critically to search for the dynamical Pauli effects predicted by the fermion dynamic symmetry model. The empirical B(E2)↑ and B(E3)↑ systematics are employed to obtain a measure of the harmonicity of the quadrupole and octupole vibrations. The fraction of the energy-weighted sum-rule strength exhausted by the sum of all known low-lying 2 + states below 2.3 MeV is found to be surprisingly constant in the 60< A<250 region except near closed shells

Low-lying magnetic dipole strength distribution in the γ-soft even-even 130-136Ba

International Nuclear Information System (INIS)

Guliyev, E.; Ertugral, F.; Kuliev, A.A.

2006-01-01

In this study the scissors mode 1 + states are systematically investigated within the rotational invariant Quasiparticle Random Phase Approximation (QRPA) for 130-136 Ba isotopes. We consider the 1 + vibrations generated by the isovector spin-spin interactions and the isoscalar and isovector quadrupole-type separable forces restoring the broken symmetry by a deformed mean field according to A.A. Kuliev et al. (Int. J. Mod. Phys. E 9, 249 (2000)). It has been shown that the restoration of the broken rotational symmetry of the Hamiltonian essentially decreases the B(M1) value of the low-lying 1 + states and increases the collectivization of the scissors mode excitations in the spectroscopic energy region. The agreement between the calculated mean excitation energies as well as the summed B(M1) value of the scissors mode excitations and the available experimental data of 134 Ba and 136 Ba is rather good. A destructive interference between the orbit and spin part of the M1 strength has been found for barium isotopes near the shell closer. For all the nuclei under investigation, the low-lying M1 transitions have ΔK=1 character as it is the case for the well-deformed nuclei. (orig.)

Predissociation of high-lying Rydberg states of molecular iodine via ion-pair states

Energy Technology Data Exchange (ETDEWEB)

Bogomolov, Alexandr S. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Grüner, Barbara; Mudrich, Marcel [Physikalisches Institut, Universität Freiburg, D-79104 Freiburg (Germany); Kochubei, Sergei A. [Institute of Semiconductor Physics, ac. Lavrent' yev ave., 13, Novosibirsk 630090 (Russian Federation); Baklanov, Alexey V. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090 (Russian Federation)

2014-03-28

Velocity map imaging of the photofragments arising from two-photon photoexcitation of molecular iodine in the energy range 73 500–74 500 cm{sup −1} covering the bands of high-lying gerade Rydberg states [{sup 2}Π{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}Π{sub 1/2}]{sub c}6d;2{sub g} has been applied. The ion signal was dominated by the atomic fragment ion I{sup +}. Up to 5 dissociation channels yielding I{sup +} ions with different kinetic energies were observed when the I{sub 2} molecule was excited within discrete peaks of Rydberg states and their satellites in this region. One of these channels gives rise to images of I{sup +} and I{sup −} ions with equal kinetic energy indicating predissociation of I{sub 2} via ion-pair states. The contribution of this channel was up to about 50% of the total I{sup +} signal. The four other channels correspond to predissociation via lower lying Rydberg states giving rise to excited iodine atoms providing I{sup +} ions by subsequent one-photon ionization by the same laser pulse. The ratio of these channels varied from peak to peak in the spectrum but their total ionic signal was always much higher than the signal of (2 + 1) resonance enhanced multi-photon ionization of I{sub 2}, which was previously considered to be the origin of ionic signal in this spectral range. The first-tier E0{sub g}{sup +} and D{sup ′}2{sub g} ion-pair states are concluded to be responsible for predissociation of Rydberg states [{sup 2}Π{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}Π{sub 1/2}]{sub c}6d;2{sub g}, respectively. Further predissociation of these ion-pair states via lower lying Rydberg states gives rise to excited I(5s{sup 2}5p{sup 4}6s{sup 1}) atoms responsible for major part of ion signal. The isotropic angular distribution of the photofragment recoil directions observed for all channels indicates that the studied Rydberg states are long-lived compared with the rotational period of the I{sub 2} molecule.

Ab initio study of small He cluster ions Hen+, n=2, 3, 4, 5, and low-lying Rydberg states of He4

International Nuclear Information System (INIS)

Staemmler, V.

1990-01-01

SCF and CEPA calculations are applied to study the structure of small He cluster ions, He n 3 , n=2, 3, 4, 5 and some low-lying Rydberg states of He 4 . The effect of electron correlation upon the equilibrium structures and binding energies is discussed. He 3 + has a linear symmetric equilibrium geometry with a bond length of 2.35 a 0 and a binding energy D e =0.165 eV with respect to He 2 + +He (experimentally: D 0 =0.17 eV which corresponds to D e ≅0.20 eV). He 4 + is a very floppy molecular ion with several energetically very similar geometrical configurations. Our CEPA calculations yield a T-shaped form with a He 3 + centre (R e =2.35 a 0 ) and one inductively bound He atom (4.39 a 0 from the central He atom of He 3 + ) as equilibrium structure. Its binding energy with respect to He 3 + +He is 0.031 eV. A linear symmetric configuration consisting of a He 2 + centre with a bond length of 2.10 a 0 and two inductively bound He atoms (4.20 a 0 from the centre of He 2 + ) is only 0.02-0.03 eV higher in energy. We expect that in larger He cluster ions structures with He 2 + and He 3 + centres and n-2 or n-3 inductively bound He atoms have nearly the same energies. In He 4 a low-lying metastable Rydberg state ( 3 π symmetry for linear He 4 * , 3 B 1 for the T-shaped form) exists which is slightly stronger bound with respect to He 3 * +He than the corresponding ion. (orig.)

Spectroscopic features of the low-lying electronic states of some sodium-helium and potassium-helium van der Waals systems

Science.gov (United States)

Chattopadhyay, Anjan

2011-08-01

Configuration interaction studies on MHe and MHe2 (where M = Na, K) systems have revealed several interesting characteristics in the properties of their low-lying electronic states. Binding energy values of the 12Π1/2, 3/2 states in MHe systems are found to be lower than the values of 12Πu (1/2, 3/2) states in the He-M-He systems by a margin of more than 200 cm-1, indicating better exciplex stabilities of the latter systems. Excited states of the other variety of the linear MHe2 (M-He-He) systems are almost repulsive. The characteristic energy barrier of the first excited spin-orbit state of alkali metal-helium systems is found to be only 15 cm-1 in KHe and 19 cm-1 in He-K-He. For the Na*He and K*He exciplexes, predicted radiative lifetime values of 18.5 ns and 29.8 ns, respectively, are in excellent agreement with the experimental values. The red-tail portions of their emission bands are contributed by M*He2 exciplexes with relatively high radiative lifetimes. The repulsive excited state of 2Σ+1/2 (or 2Σ+g,1/2) symmetry in these van der Waals systems is likely to play an important role in the pumping of the blue side of the ns2S1/2 → np2P3/2 transition, which eventually may give rise to the np2P1/2 → ns2S1/2 lasing transition.

Spectroscopic features of the low-lying electronic states of some sodium-helium and potassium-helium van der Waals systems

International Nuclear Information System (INIS)

Chattopadhyay, Anjan

2011-01-01

Configuration interaction studies on MHe and MHe 2 (where M = Na, K) systems have revealed several interesting characteristics in the properties of their low-lying electronic states. Binding energy values of the 1 2 Π 1/2,3/2 states in MHe systems are found to be lower than the values of 1 2 Π u(1/2,3/2) states in the He-M-He systems by a margin of more than 200 cm -1 , indicating better exciplex stabilities of the latter systems. Excited states of the other variety of the linear MHe 2 (M-He-He) systems are almost repulsive. The characteristic energy barrier of the first excited spin-orbit state of alkali metal-helium systems is found to be only 15 cm -1 in KHe and 19 cm -1 in He-K-He. For the Na*He and K*He exciplexes, predicted radiative lifetime values of 18.5 ns and 29.8 ns, respectively, are in excellent agreement with the experimental values. The red-tail portions of their emission bands are contributed by M*He 2 exciplexes with relatively high radiative lifetimes. The repulsive excited state of 2 Σ + 1/2 (or 2 Σ + g,1/2 ) symmetry in these van der Waals systems is likely to play an important role in the pumping of the blue side of the ns 2 S 1/2 → np 2 P 3/2 transition, which eventually may give rise to the np 2 P 1/2 → ns 2 S 1/2 lasing transition.

Selective excitation of atoms or molecules to high-lying states

International Nuclear Information System (INIS)

Ducas, T.W.

1978-01-01

This specification relates to the selective excitation of atoms or molecules to high lying states and a method of separating different isotopes of the same element by selective excitation of the isotopes. (U.K.)

Nuclear Compton scattering

International Nuclear Information System (INIS)

Christillin, P.

1986-01-01

The theory of nuclear Compton scattering is reformulated with explicit consideration of both virtual and real pionic degrees of freedom. The effects due to low-lying nuclear states, to seagull terms, to pion condensation and to the Δ dynamics in the nucleus and their interplay in the different energy regions are examined. It is shown that all corrections to the one-body terms, of diffractive behaviour determined by the nuclear form factor, have an effective two-body character. The possibility of using Compton scattering as a complementary source of information about nuclear dynamics is restressed. (author)

Concise nuclear isobar charts

Energy Technology Data Exchange (ETDEWEB)

Bucka, H.

1986-01-01

In the Concise Nuclear Isobar Charts, data on binding energies of protons and neutrons in the ground state and excitation energies for low-lying nuclear energy levels are displayed, both of which are of great interest for transition processes as well as for questions of nuclear structure. Also, quantum numbers for angular momentum and parity are shown for these energy levels. For the stable nuclei, data for the relative abundances, and for unstable nucleon configurations, the transition probabilities are included in the data displayed. Due to the representation chosen for the atomic nuclei, in many cases a very clear first survey of systematic properties of nuclear energy states as well as spontaneous decay processes is achieved.

The scaling dimension of low lying Dirac eigenmodes and of the topological charge density

CERN Document Server

Aubin, C.; Gottlieb, Steven; Gregory, E.B.; Heller, Urs M.; Hetrick, J.E.; Osborn, J.; Sugar, R.; Toussaint, D.; de Forcrand, Ph.; Jahn, Oliver

2005-01-01

As a quantitative measure of localization, the inverse participation ratio of low lying Dirac eigenmodes and topological charge density is calculated on quenched lattices over a wide range of lattice spacings and volumes. Since different topological objects (instantons, vortices, monopoles, and artifacts) have different co-dimension, scaling analysis provides information on the amount of each present and their correlation with the localization of low lying eigenmodes.

The low-lying electronic states of BeP: a reliable and accurate quantum mechanical prediction

International Nuclear Information System (INIS)

Ornellas, Fernando R

2009-01-01

A very high level of theoretical treatment (complete active space self-consistent field CASSCF/MRCI/aug-cc-pV5Z) was used to characterize the spectroscopic properties of a manifold of quartet and doublet states of the species BeP, as yet experimentally unknown. Potential energy curves for 11 electronic states were obtained, as well as the associated vibrational energy levels, and a whole set of spectroscopic constants. Dipole moment functions and vibrationally averaged dipole moments were also evaluated. Similarities and differences between BeN and BeP were analysed along with the isovalent SiB species. The molecule BeP has a X 4 Σ - ground state, with an equilibrium bond distance of 2.073 A, and a harmonic frequency of 516.2 cm -1 ; it is followed closely by the states 2 Π (R e = 2.081 A, ω e = 639.6 cm -1 ) and 2 Σ - (R e = 2.074 A, ω e = 536.5 cm -1 ), at 502 and 1976 cm -1 , respectively. The other quartets investigated, A 4 Π (R e = 1.991 A, ω e = 555.3 cm -1 ) and B 4 Σ - (R e = 2.758 A, ω e = 292.2 cm -1 ) lie at 13 291 and 24 394 cm -1 , respectively. The remaining doublets ( 2 Δ, 2 Σ + (2) and 2 Π(3)) all fall below 28 000 cm -1 . Avoided crossings between the 2 Σ + states and between the 2 Π states add an extra complexity to this manifold of states.

Electroexcitation of Low-Lying Particle-Hole RPA States of 16O with WBP Interaction

Science.gov (United States)

Ali, H. Taqi; R. A., Radhi; Adil, M. Hussein

2014-12-01

The nuclear structure of 16O is studied in the framework of the particle-hole random phase approximation (ph RPA). The Hamiltonian is diagonalized within a model space with particle orbits {1d5/2,1d3/2, and 2s1/2} and the hole orbits {1p3/2 and 1p1/2} using Warburton and Brown interaction WBP. The ph RPA calculations are tested, by comparing the electron scattering form factors with the available experimental data. The results of electron scattering form factors and reduced transition strength for the states: 1-, T = 0 (7.116 MeV); 2-, T = 1 (12.968 MeV); 2-, T = 1 (20.412 MeV); and 3-, T = 0 (6.129 MeV) are interpreted in terms of the harmonic-oscillator (HO) wave functions of size parameter b. The occupation probabilities of the single particle and hole orbits are calculated. The spurious states are removed by adding the center of mass (CM) correction to the nuclear Hamiltonian. A comparison with the available experiments data is presented.

Microscopic study of low-lying yrast spectra and deformation ...

Indian Academy of Sciences (India)

73, No. 4. — journal of. October 2009 physics pp. 657–668. Microscopic study of low-lying yrast spectra and deformation systematics in neutron-rich. 98−106Sr isotopes ... with a large and rigid moment of inertia. 98Sr is predicted to have a ... 2 energy as neutron number N changes from 58 to 60. The onset of deformation in ...

Spectroscopic features of the low-lying electronic states of some sodium-helium and potassium-helium van der Waals systems

Energy Technology Data Exchange (ETDEWEB)

Chattopadhyay, Anjan, E-mail: anjan@bits-goa.ac.in, E-mail: anjan_chattopadhyay@yahoo.com [Department of Chemistry, Birla Institute of Technology and Science (BITS), Pilani -K.K. Birla Goa Campus, Goa, 403 726 (India)

2011-08-28

Configuration interaction studies on MHe and MHe{sub 2} (where M = Na, K) systems have revealed several interesting characteristics in the properties of their low-lying electronic states. Binding energy values of the 1{sup 2}{Pi}{sub 1/2,3/2} states in MHe systems are found to be lower than the values of 1{sup 2}{Pi}{sub u(1/2,3/2)} states in the He-M-He systems by a margin of more than 200 cm{sup -1}, indicating better exciplex stabilities of the latter systems. Excited states of the other variety of the linear MHe{sub 2} (M-He-He) systems are almost repulsive. The characteristic energy barrier of the first excited spin-orbit state of alkali metal-helium systems is found to be only 15 cm{sup -1} in KHe and 19 cm{sup -1} in He-K-He. For the Na*He and K*He exciplexes, predicted radiative lifetime values of 18.5 ns and 29.8 ns, respectively, are in excellent agreement with the experimental values. The red-tail portions of their emission bands are contributed by M*He{sub 2} exciplexes with relatively high radiative lifetimes. The repulsive excited state of {sup 2}{Sigma}{sup +}{sub 1/2} (or {sup 2}{Sigma}{sup +}{sub g,1/2}) symmetry in these van der Waals systems is likely to play an important role in the pumping of the blue side of the ns{sup 2}S{sub 1/2} {yields} np{sup 2}P{sub 3/2} transition, which eventually may give rise to the np{sup 2}P{sub 1/2} {yields} ns{sup 2}S{sub 1/2} lasing transition.

More evidence of localization in the low-lying Dirac spectrum

CERN Document Server

Bernard, C; Gottlieb, Steven; Levkova, L.; Heller, U.M.; Hetrick, J.E.; Jahn, O.; Maresca, F.; Renner, Dru Bryant; Toussaint, D.; Sugar, R.; Forcrand, Ph. de; Gottlieb, Steven

2006-01-01

We have extended our computation of the inverse participation ratio of low-lying (asqtad) Dirac eigenvectors in quenched SU(3). The scaling dimension of the confining manifold is clearer and very near 3. We have also computed the 2-point correlator which further characterizes the localization.

Decay modes of high-lying excitations in nuclei

International Nuclear Information System (INIS)

Gales, S.

1993-01-01

Inelastic, charge-exchange and transfer reactions induced by hadronic probes at intermediate energies have revealed a rich spectrum of new high-lying modes embedded in the nuclear continuum. The investigation of their decay properties is believed to be a severe test of their microscopic structure as predicted by nuclear models. In addition the degree of damping of these simple modes in the nuclear continuum can be obtained by means of the measured branching ratios to the various decay channels as compared to statistical model calculations. As illustrative examples the decay modes of high-spin single-particle states and isovector resonances are discussed. (author) 23 refs.; 14 figs

The structure of low-lying states in ${}^{140}$Sm studied by Coulomb excitation

CERN Document Server

Klintefjord, M.; Görgen, A.; Bauer, C.; Bello Garrote, F.L.; Bönig, S.; Bounthong, B.; Damyanova, A.; Delaroche, J.P.; Fedosseev, V.; Fink, D.A.; Giacoppo, F.; Girod, M.; Hoff, P.; Imai, N.; Korten, W.; Larsen, A.C.; Libert, J.; Lutter, R.; Marsh, B.A.; Molkanov, P.L.; Naïdja, H.; Napiorkowski, P.; Nowacki, F.; Pakarinen, J.; Rapisarda, E.; Reiter, P.; Renstrøm, T.; Rothe, S.; Seliverstov, M.D.; Siebeck, B.; Siem, S.; Srebrny, J.; Stora, T.; Thöle, P.; Tornyi, T.G.; Tveten, G.M.; Van Duppen, P.; Vermeulen, M.J.; Voulot, D.; Warr, N.; Wenander, F.; De Witte, H.; Zielińska, M.

2016-05-02

The electromagnetic structure of $^{140}$Sm was studied in a low-energy Coulomb excitation experiment with a radioactive ion beam from the REX-ISOLDE facility at CERN. The $2^+$ and $4^+$ states of the ground-state band and a second $2^+$ state were populated by multi-step excitation. The analysis of the differential Coulomb excitation cross sections yielded reduced transition probabilities between all observed states and the spectroscopic quadrupole moment for the $2_1^+$ state. The experimental results are compared to large-scale shell model calculations and beyond-mean-field calculations based on the Gogny D1S interaction with a five-dimensional collective Hamiltonian formalism. Simpler geometric and algebraic models are also employed to interpret the experimental data. The results indicate that $^{140}$Sm shows considerable $\\gamma$ softness, but in contrast to earlier speculation no signs of shape coexistence at low excitation energy. This work sheds more light on the onset of deformation and collectivit...

Boson realizations of Lie algebras with applications to nuclear physics

International Nuclear Information System (INIS)

Klein, A.; Marshalek, E.R.

1991-01-01

The concept of boson realization (or mapping) of Lie algebras appeared first in nuclear physics in 1962 as the idea of expanding bilinear forms in fermion creation and annihilation operators in Taylor series of boson operators, with the object of converting the study of nuclear vibrational motion into a problem of coupled oscillators. The physical situations of interest are quite diverse, depending, for instance, on whether excitations for fixed- or variable-particle number are being studied, on how total angular momentum is decomposed into orbital and spin parts, and on whether isotopic spin and other intrinsic degrees of freedom enter. As a consequence, all of the semisimple algebras other than the exceptional ones have proved to be of interest at one time or another, and all are studied in this review. Though the salient historical facts are presented in the introduction, in the body of the review the progression is (generally) from the simplest algebras to the more complex ones. With a sufficiently broad view of the physics requirements, the mathematical problem is the realization of an arbitrary representation of a Lie algebra in a subspace of a suitably chosen Hilbert space of bosons (Heisenberg-Weyl algebra). Indeed, if one includes the study of odd nuclei, one is forced to consider the mappings to spaces that are direct-product spaces of bosons and (quasi)fermions. Though all the methods that have been used for these problems are reviewed, emphasis is placed on a relatively new algebraic method that has emerged over the past decade. Many of the classic results are rederived, and some new results are obtained for odd systems

DECAY MODES OF HIGH-LYING SINGLE-PARTICLE STATES IN PB-209

NARCIS (Netherlands)

BEAUMEL, D; FORTIER, S; GALES, S; GUILLOT, J; LANGEVINJOLIOT, H; LAURENT, H; MAISON, JM; VERNOTTE, J; BORDEWIJK, JA; BRANDENBURG, S; KRASZNAHORKAY, A; CRAWLEY, GM; MASSOLO, CP; RENTERIA, M

The neutron decay of high-lying single-particle states in Pb-209 excited by means of the (alpha, He-3) reaction has been investigated at 122 MeV incident energy using a multidetector array. The high-spin values of these states, inferred from previous inclusive experiments, are confirmed by the

Erratum to: Quadrupole moments of low-lying baryons with spin ...

Indian Academy of Sciences (India)

physics pp. 1083. Erratum to: Quadrupole moments of low-lying baryons with spin-. 1. 2. +. , spin-. 3. 2. +. , and spin-. 3. 2. +. → 1. 2. + transitions. NEETIKA SHARMA and HARLEEN DAHIYA. ∗. Department of Physics, Dr. B.R. Ambedkar National Institute of Technology,. Jalandhar 144 011, India. ∗. Corresponding author.

Mass spectrum of low-lying baryons in the ground state in a relativistic potential model of independent quarks with chiral symmetry

International Nuclear Information System (INIS)

Barik, N.; Dash, B.K.

1986-01-01

Under the assumption that baryons are an assembly of independent quarks, confined in a first approximation by an effective potential U(r) = 1/2(1+γ 0 )(ar 2 +V 0 ) which presumably represents the nonperturbative gluon interactions, the mass spectrum of the low-lying ground-state baryons has been calculated by considering perturbatively the contributions of the residual quark-pion coupling arising out of the requirement of chiral symmetry and that of the quark-gluon coupling due to one-gluon exchange over and above the necessary center-of-mass correction. The physical masses of the baryons so obtained agree quite well with the corresponding experimental value. The strong coupling constant α/sub c/ = 0.58 required here to describe the QCD mass splittings is quite consistent with the idea of treating one-gluon-exchange effects in lowest-order perturbation theory

Low-temperature nuclear heat applications: Nuclear power plants for district heating

International Nuclear Information System (INIS)

1987-08-01

The IAEA reflected the needs of its Member States for the exchange of information in the field of nuclear heat application already in the late 1970s. In the early 1980s, some Member States showed their interest in the use of heat from electricity producing nuclear power plants and in the development of nuclear heating plants. Accordingly, a technical committee meeting with a workshop was organized in 1983 to review the status of nuclear heat application which confirmed both the progress made in this field and the renewed interest of Member States in an active exchange of information about this subject. In 1985 an Advisory Group summarized the Potential of Low-Temperature Nuclear Heat Application; the relevant Technical Document reviewing the situation in the IAEA's Member States was issued in 1986 (IAEA-TECDOC-397). Programme plans were made for 1986-88 and the IAEA was asked to promote the exchange of information, with specific emphasis on the design criteria, operating experience, safety requirements and specifications for heat-only reactors, co-generation plants and power plants adapted for heat application. Because of a growing interest of the IAEA's Member States about nuclear heat employment in the district heating domaine, an Advisory Group meeting was organized by the IAEA on ''Low-Temperature Nuclear Heat Application: Nuclear Power Plants for District Heating'' in Prague, Czechoslovakia in June 1986. The information gained up to 1986 and discussed during this meeting is embodied in the present Technical Document. 22 figs, 11 tabs

Low-lying charmed and charmed-strange baryon states

Energy Technology Data Exchange (ETDEWEB)

Chen, Bing [Anyang Normal University, Department of Physics, Anyang (China); Institute of Modern Physics of CAS and Lanzhou University, Research Center for Hadron and CSR Physics, Lanzhou (China); Wei, Ke-Wei [Anyang Normal University, Department of Physics, Anyang (China); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Institute of Modern Physics of CAS and Lanzhou University, Research Center for Hadron and CSR Physics, Lanzhou (China); Matsuki, Takayuki [Tokyo Kasei University, Tokyo (Japan); Nishina Center, RIKEN, Theoretical Research Division, Saitama (Japan)

2017-03-15

In this work, we systematically study the mass spectra and strong decays of 1P and 2S charmed and charmed-strange baryons in the framework of non-relativistic constituent quark models. With the light quark cluster-heavy quark picture, the masses are simply calculated by a potential model. The strong decays are studied by the Eichten-Hill-Quigg decay formula. Masses and decay properties of the well-established 1S and 1P states can be reproduced by our method. Σ{sub c}(2800){sup 0,+,++} can be assigned as a Σ{sub c2}(3/2{sup -}) or Σ{sub c2}(5/2{sup -}) state. We prefer to interpret the signal Σ{sub c}(2850){sup 0} as a 2S(1/2{sup +}) state although at present we cannot thoroughly exclude the possibility that this is the same state as Σ{sub c}(2800){sup 0}. Λ{sub c}(2765){sup +} or Σ{sub c}(2765){sup +} could be explained as the Λ{sub c}{sup +}(2S) state or Σ{sup +}{sub c1}(1/2{sup -}) state, respectively. We propose to measure the branching ratio of B(Σ{sub c}(2455)π)/B(Σ{sub c}(2520)π) in the future, which may disentangle the puzzle of this state. Our results support Ξ{sub c}(2980){sup 0,+} as the first radial excited state of Ξ{sub c}(2470){sup 0,+} with J{sup P} = 1/2{sup +}. The assignment of Ξ{sub c}(2930){sup 0} is analogous to Σ{sub c}(2800){sup 0,+,++}, i.e., a Ξ{sup '}{sub c2}(3/2{sup -}) or Ξ{sup '}{sub c2}(5/2{sup -}) state. In addition, we predict some typical ratios among partial decay widths, which are valuable for experimental search for these missing charmed and charmed-strange baryons. (orig.)

Earthquakes - a danger to deep-lying repositories?

International Nuclear Information System (INIS)

2012-03-01

This booklet issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at geological factors concerning earthquakes and the safety of deep-lying repositories for nuclear waste. The geological processes involved in the occurrence of earthquakes are briefly looked at and the definitions for magnitude and intensity of earthquakes are discussed. Examples of damage caused by earthquakes are given. The earthquake situation in Switzerland is looked at and the effects of earthquakes on sub-surface structures and deep-lying repositories are discussed. Finally, the ideas proposed for deep-lying geological repositories for nuclear wastes are discussed

Muon nuclear fusion and low temperature nuclear fusion

International Nuclear Information System (INIS)

Nagamine, Kanetada

1990-01-01

Low temperature (or normal temperature) nuclear fusion is one of the phenomena causing nuclear fusion without requiring high temperature. In thermal nuclear fusion, the Coulomb barrier is overcome with the help of thermal energy, but in the low temperature nuclear fusion, the Coulomb barrier is neutralized by the introduction of the particles having larger mass than electrons and negative charges, at this time, if two nuclei can approach to the distance of 10 -13 cm in the neutral state, the occurrence of nuclear fusion reaction is expected. As the mass of the particles is heavier, the neutral region is smaller, and nuclear fusion is easy to occur. The particles to meet this purpose are the electrons within substances and muons. The research on muon nuclear fusion became suddenly active in the latter half of 1970s, the cause of which was the discovery of the fact that the formation of muons occurs resonantly rapidly in D-T and D-D systems. Muons are the unstable elementary particles having the life of 2.2 μs, and they can have positive and negative charges. In the muon catalyzed fusion, the muons with negative charge take part. The principle of the muon catalyzed fusion, its present status and future perspective, and the present status of low temperature nuclear fusion are reported. (K.I.)

Nuclear power in the United States

International Nuclear Information System (INIS)

Johnston, J.B.

1985-01-01

All over the world except in the United States, nuclear energy is a low cost, secure, environmentally acceptable form of energy. In the United States, civilian nuclear power is dead. 112 nuclear power plants have been abandoned or cancelled in the last decade, and there has been no new order for nuclear plants since 1978. It will be fortunate to have 125 operating nuclear plants in the United States in the year 2000. There are almost 90 completed nuclear power plants and about 45 under construction in the United States, but several of those under construction will eventually be abandoned. About 20 % of the electricity in the United States will be generated by nuclear plants in 2000 as compared with 13 % supplied in the last year. Under the present regulatory and institutional arrangement, American electric utilities would not consider to order a new nuclear power plant. Post-TMI nuclear plants became very expensive, and there is also ideological opposition to nuclear power. Coal-firing plants are also in the similar situation. The uncertainty about electric power demand, the cost of money, the inflation of construction cost and regulation caused the situation. (Kako, I.)

Symmetrized density matrix renormalization group algorithm for low-lying excited states of conjugated carbon systems: Application to 1,12-benzoperylene and polychrysene

Science.gov (United States)

Prodhan, Suryoday; Ramasesha, S.

2018-05-01

The symmetry adapted density matrix renormalization group (SDMRG) technique has been an efficient method for studying low-lying eigenstates in one- and quasi-one-dimensional electronic systems. However, the SDMRG method had bottlenecks involving the construction of linearly independent symmetry adapted basis states as the symmetry matrices in the DMRG basis were not sparse. We have developed a modified algorithm to overcome this bottleneck. The new method incorporates end-to-end interchange symmetry (C2) , electron-hole symmetry (J ) , and parity or spin-flip symmetry (P ) in these calculations. The one-to-one correspondence between direct-product basis states in the DMRG Hilbert space for these symmetry operations renders the symmetry matrices in the new basis with maximum sparseness, just one nonzero matrix element per row. Using methods similar to those employed in the exact diagonalization technique for Pariser-Parr-Pople (PPP) models, developed in the 1980s, it is possible to construct orthogonal SDMRG basis states while bypassing the slow step of the Gram-Schmidt orthonormalization procedure. The method together with the PPP model which incorporates long-range electronic correlations is employed to study the correlated excited-state spectra of 1,12-benzoperylene and a narrow mixed graphene nanoribbon with a chrysene molecule as the building unit, comprising both zigzag and cove-edge structures.

Factors associated with low-lying intrauterine devices: a cross-sectional ultrasound study in a cohort of African-American women.

Science.gov (United States)

Moshesh, Malana; Saldana, Tina; Deans, Elizabeth; Cooper, Tracy; Baird, Donna

2018-03-14

The object of this study is to examine factors and symptoms associated with low-lying IUDs as defined by ultrasound. This is a cross-sectional sub-study of participants in the Study of Environment, Life-style, and Fibroids (SELF). SELF participants had screening ultrasounds for fibroids at study enrollment; those with an IUD in place are included in this sub-study. Low-lying IUDs were identified and localized. Logistic regression was used to identify factors and symptoms associated with low-lying IUDs. Among 168 women with IUDs at ultrasound, 28 (17%) had a low-lying IUD. Having a low-lying IUD was associated with low education level (≤high school: aOR 3.1 95% CI 1.14-8.55) and with increased BMI (p=.002). Women with a low-lying IUD were more likely to report a "big problem" with dysmenorrhea (the highest option of the Likert scale) as compared to women with a normally-positioned IUD (OR 3.2 95% CI 1.07-9.54). Our study found that women with a low-lying IUD are more likely to be of lower education and higher BMI, and to report more dysmenorrhea. Women who are obese may benefit from additional counseling and closer follow-up after IUD placement. Future research is warranted to investigate IUD placement and possible IUD migration among women who are obese. Copyright © 2018 Elsevier Inc. All rights reserved.

Low-lying (K ) states of gadolinium isotopes

Indian Academy of Sciences (India)

excitation on energy levels as possible as determined has become a research field ... exist and it is clearly interesting to determine how many such excitations ..... states may be common near and above the pairing gap in deformed nuclei.

Calculations of the Low-Lying Structures in the Even-Even Nd/Sm/Gd/Dy Isotopes

Science.gov (United States)

Lee, Su Youn; Lee, J. H.; Lee, Young Jun

2018-05-01

The nuclear structure of deformed nuclei has been studied using the interacting boson model (IBM). In this study, energy levels and E2 transition probabilities were determined for even nuclei in the Nd/Sm/Gd/Dy chains which have a transition characteristic between the rotational, SU(3) and vibrational, U(5) limits. The structure of the nuclei exhibits a slight breaking of the SU(3) symmetry in the direction of U(5), and therefore, we add the d-boson number operator n d , which is the main term of the U(5) symmetric Hamiltonian, to the SU(3) Hamiltonian of the IBM. The calculated results for low-lying energy levels and E2 transition rates in Nd/Sm/Gd/Dy isotopes are in reasonably good agreement with known experimental results.

Low-energy nuclear physics

International Nuclear Information System (INIS)

1985-01-01

The 1985 annual report of the Schuster Laboratory, Manchester University, England, on low-energy nuclear physics, is presented. The report includes experiments involving: high spin states, nuclei far from stability, reactions and fission, spectroscopy and related subjects. Technical developments are also described. (U.K.)

Lowest lying 2+ and 3- vibrational states in Pb, Sn, and Ni isotopes in relativistic quasiparticle random-phase approximation

International Nuclear Information System (INIS)

Ansari, A.; Ring, P.

2006-01-01

The excitation energies and electric multipole decay rates of the lowest lying 2 + and 3 - vibrational states in Pb, Sn, and Ni nuclei are calculated following relativistic quasiparticle random-phase approximation formalism based on the relativistic Hartree-Bogoliubov mean field. Two sets of Lagrangian parameters, NL1 and NL3, are used to investigate the effect of the nuclear force. Overall there is good agreement with the available experimental data for a wide range of mass numbers considered here, and the NL3 set seems to be a better choice. However, strictly speaking, these studies point toward the need of a new set of force parameters that could produce more realistic single-particle levels, at least in vicinity of the Fermi surface, of a wide range of nuclear masses

Systematics on the low-lying spectra in N = 78 ~ 80 isotones

International Nuclear Information System (INIS)

Cheng, Y.Y.; Zhang, S.Q.; Li, X.Q.

2014-01-01

Combining the new spectroscopy results of 144 Tb and previous spectroscopy studies of neighboring nuclei, a systematic investigation on the low-lying spectra in N = 78 ~ 80 isotones is performed. Good systematics have been found for the coupling patterns which couple the odd nucleon(s), such as πh 11/2 , νh 11/2 —1 , νh 11/2 2 , νh 11/2 —2 , νh 11/2 —1 , to the 2 + , 4 + , 6 + and 3 - core excitations. It is found that the relative excitation energies of the states formed by coupling h 11/2 proton(s) to the 2 + , 4 + core excitations are pushed up, in contrast with those formed by coupling h 11/2 neutron hole(s) to the 2 + , 4 + core excitations, which are pulled down. According to the systematics, the interpretation that the 17/2 + states observed in 141 Sm and 143 Gd are the fully aligned member of coupling the odd h 11/2 neutron hole to the octupole 3 - core excitation, is explored to the isotones 145 Dy, 142 Eu, and 144 Tb. (author)

Effects of pairing correlation on low-lying quasi-particle resonance in neutron drip-line nuclei

OpenAIRE

Kobayashi, Yoshihiko; Matsuo, Masayuki

2015-01-01

We discuss effects of pairing correlation on quasi-particle resonance. We analyze in detail how the width of low-lying quasi-particle resonance is governed by the pairing correlation in the neutron drip-line nuclei. We consider the 46Si + n system to discuss low-lying p wave quasi-particle resonance. Solving the Hartree-Fock-Bogoliubov equation in the coordinate space with scattering boundary condition, we calculate the phase shift, the elastic cross section, the resonance width and the reson...

Probing shape coexistence in neutron-deficient $^{72}$Se via low-energy Coulomb excitation

CERN Multimedia

We propose to study the evolution of nuclear structure in neutron-­deficient $^{72}$Se by performing a low-­energy Coulomb excitation measurement. Matrix elements will be determined for low-­lying excited states allowing for a full comparison with theoretical predictions. Furthermore, the intrinsic shape of the ground state, and the second 0$^{+}$ state, will be investigated using the quadrupole sum rules method.

All Electron ab initio Investigations of the Three Lowest Lying Electronic States of the RuC Molecule

DEFF Research Database (Denmark)

Shim, Irene; Gingerich, K. A.

2000-01-01

The three lowest-lying electronic states of RuC, (1)Sigma(+), (3)Delta, and (1)Delta, have been investigated by performing all-electron ab initio multi-configuration self-consistent-field (CASSCF) and multi-reference configuration interaction (MRCI) calculations including relativistic corrections....... The electronic ground state is derived as (1)Sigma(+) with the spectroscopic constants r(e) = 1.616 Angstrom and omega(e) = 1085 cm(-1). The lowest-lying excited state, (3)Delta, has r(e) = 1.632 Angstrom, omega(e) = 1063 cm(-1), and T-e = 912 cm(-1). These results are consistent with recent spectroscopic values....... The chemical bonds in all three lowest-lying states are triple bonds composed of one sigma and two pi bonds. (C) 2000 Elsevier Science B.V. All rights reserved....

Energies and electric dipole transitions for low-lying levels of protactinium IV and uranium V

Energy Technology Data Exchange (ETDEWEB)

Uerer, Gueldem; Oezdemir, Leyla [Sakarya Univ. (Turkey). Physics Dept.

2012-01-15

We have reported a relativistic multiconfiguration Dirac-Fock (MCDF) study on low-lying level structures of protactinium IV (Z = 91) and uranium V (Z = 92) ions. Excitation energies and electric dipole (E1) transition parameters (wavelengths, oscillator strengths, and transition rates) for these low-lying levels have been given. We have also investigated the influence of the transverse Breit and quantum electrodynamic (QED) contributions besides correlation effects on the level structure. A comparison has been made with a few available data for these ions in the literature. (orig.)

Microscopic description of low-lying M1 excitations in odd-mass actinide nuclei

Energy Technology Data Exchange (ETDEWEB)

Tabar, Emre, E-mail: etabar@sakarya.edu.tr [Physics Department, Sakarya University, 54187 Sakarya (Turkey); Biomedical, Magnetic and Semiconductor Materials Research Center (BIMAS-RC), Sakarya University, 54187 Sakarya (Turkey); Yakut, Hakan, E-mail: hyakut@sakarya.edu.tr [Physics Department, Sakarya University, 54187 Sakarya (Turkey); Biomedical, Magnetic and Semiconductor Materials Research Center (BIMAS-RC), Sakarya University, 54187 Sakarya (Turkey); Kuliev, Ali Akbar [Azerbaijan National Academy of Aviation, Baku (Azerbaijan)

2017-01-15

A restoration method of a broken symmetry which allows self-consistent determination of the separable effective restoration forces is now adapted to odd-mass nuclei in order to restore violated rotational invariance (RI-) of the Quasiparticle Phonon Nuclear Model (QPNM) Hamiltonian. Because of the self-consistency of the method, these effective forces contain no arbitrary parameters. Within RI-QPNM, the properties of the low-lying magnetic dipole excitations in odd-mass deformed {sup 229–233}Th and {sup 233–239}U nuclei have been investigated for the first time. It has been shown that computed fragmentation of the M1 strengths below 4 MeV in these nuclei is much stronger than that in neighboring doubly even {sup 228–232}Th and {sup 232–238}U nuclei. For {sup 235}U the summed M1 strength in the energy range 1.5–2.8 MeV is in agreement with the relevant experimental data where the missing strength was extracted by means of a fluctuation analysis.

Hierarchy of the low-lying excitations for the (2+1-dimensional q=3 Potts model in the ordered phase

Directory of Open Access Journals (Sweden)

Yoshihiro Nishiyama

2017-03-01

Full Text Available The (2+1-dimensional q=3 Potts model was simulated with the exact diagonalization method. In the ordered phase, the elementary excitations (magnons are attractive, forming a series of bound states in the low-energy spectrum. We investigate the low-lying spectrum through a dynamical susceptibility, which is readily tractable with the exact diagonalization method via the continued-fraction expansion. As a result, we estimate the series of (scaled mass gaps, m2,3,4/m1 (m1: single-magnon mass, in proximity to the transition point.

Study of the β{sup -} decay of {sup 116m1}In: A new interpretation of low-lying 0{sup +} states in {sup 116}Sn

Energy Technology Data Exchange (ETDEWEB)

Pore, J.L.; Cross, D.S.; Andreoiu, C.; Ashley, R.; Chester, A.S.; Noakes, B.; Starosta, K.; Voss, P.J. [Simon Fraser University, Department of Chemistry, Burnaby BC (Canada); Ball, G.C.; Bender, P.C.; Garnsworthy, A.B.; Hackman, G.; Rajabali, M.M. [TRIUMF, Vancouver BC (Canada); Diaz Varela, A.; Demand, G.A.; Dunlop, R.; Garrett, P.E.; Hadinia, B.; Jigmeddorj, B.; Laffoley, A.T.; Liblong, A.; Svensson, C.E. [University of Guelph, Department of Physics, Guelph ON (Canada); Kanungo, R. [Saint Mary' s University, Department of Astronomy and Physics, Halifax NS (Canada); Petrache, C.M. [Universite Paris-Saclay, CSNSM, CNRS-IN2P3, Orsay Cedex (France); Wang, Z.M. [Simon Fraser University, Department of Chemistry, Burnaby BC (Canada); TRIUMF, Vancouver BC (Canada); Wood, J.L. [Georgia Institute of Technology, School of Physics, Atlanta, GA (United States); Yates, S.W. [University of Kentucky, Departments of Chemistry and Physics and Astronomy, Lexington, KY (United States)

2017-02-15

The {sup 116}Sn nucleus contains a collective rotational band originating from proton π 2p-2h excitations across the proton Z = 50 shell gap. Even though this nucleus has been extensively investigated in the past, there was still missing information on the low-energy interband transitions connecting the intruder and normal structures. The low-lying structure of {sup 116}Sn was investigated through a high-statistics study of the β{sup -} decay of {sup 116m1}In with the 8π spectrometer and its ancillary detectors at TRIUMF. These measurements are critical in order to properly characterize the π 2p-2h rotational band. Weak γ-decay branches are observed utilizing γ-γ coincidence spectroscopy methods, leading to the first direct observation of the 85 keV 2{sub 2}{sup +} → 0{sub 3}{sup +} γ ray with a transition strength of B(E2) = 99.7(84) W.u. The analysis of these results strongly suggests that the 2027 keV 0{sub 3}{sup +} state should replace the previously assigned 1757 keV 0{sub 2}{sup +} state as the band-head of the π 2p-2h rotational band. (orig.)

Lie algebras and applications

CERN Document Server

Iachello, Francesco

2015-01-01

This course-based primer provides an introduction to Lie algebras and some of their applications to the spectroscopy of molecules, atoms, nuclei and hadrons. In the first part, it concisely presents the basic concepts of Lie algebras, their representations and their invariants. The second part includes a description of how Lie algebras are used in practice in the treatment of bosonic and fermionic systems. Physical applications considered include rotations and vibrations of molecules (vibron model), collective modes in nuclei (interacting boson model), the atomic shell model, the nuclear shell model, and the quark model of hadrons. One of the key concepts in the application of Lie algebraic methods in physics, that of spectrum generating algebras and their associated dynamic symmetries, is also discussed. The book highlights a number of examples that help to illustrate the abstract algebraic definitions and includes a summary of many formulas of practical interest, such as the eigenvalues of Casimir operators...

E0 and E2 decay of low-lying 0+ states in the even-even nuclei 206Pb, 208Po, 112-120 Sn and 112114Cd

International Nuclear Information System (INIS)

Julin, Rauno.

1979-04-01

Several new methods of in-beam conversion-electron and γ-ray spectrometry, applicable in the determination of E0 and E2 decay properties of low-lying 0 + states in even-mass nuclei, have been developed. The main attention has been paid to direct lifetime-measurement and coincidence methods based on the use of the natural pulsing of a cyclotron beam. With the aid of these methods, the similarity of the absolute decay rates of the two-neutron-hole 0 + 2 states in the N = 124 nuclei 206 Pb and 208 Po has been shown. A systematic investigation of the de-excitation of the 0 + 2 and 0 + 3 states in 112 , 11 4 , 116 , 118 , 120 Sn has been carried out. Twelve E0 transitions connecting the 0 + states have been observed, including very strong low-energy E0 transitions between the excited 0 + states, and several absolute transition probabilities have been determined. Furthermore, the new techniques have been applied successfully in determining the absolute E0 and E2 transition rates from the 0 + 2 and 0 + 3 states in 112 Cd and 114 Cd. The use of isotope-shift data in the calculation of the monopole strengths in 206 Pb and 208 Po is discussed. The results on even Sn and Cd nuclei are discussed within the framework of the coexistence of different shapes and of configuration mixing. (author)

Low- and high-density nuclear equation of state and the hyperon puzzle

Energy Technology Data Exchange (ETDEWEB)

Colucci, Giuseppe; Sedrakian, Armen [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik

2013-07-01

The measurements of the unusually high mass of the millisecond pulsar PSR J1614-2230 (1.97 ± 0.04 M {sub CircleDot}) imposes a strong constraint on the nuclear Equation of State (EoS), in particular for what concerns the finite density behaviour of nuclear and neutron matter. In my talk I first discuss a model for the low-density part of the EoS, based on chiral one-pion exchange. I consider a self-consistent approach at finite temperature and density and show that even in a fully-relativistic theory the one-pion exchange contribution is dominated by a contact interaction. Then, a relativistic mean-field approach is used to discuss the high-density part of the EoS, including the presence of hyperons. In the latter, a density dependent parametrization is used and a parameter study on the hyperon-scalar meson coupling is performed.

Excitation of higher lying energy states in a rubidium DPAL

Science.gov (United States)

Wallerstein, A. J.; Perram, Glen; Rice, Christopher A.

2018-02-01

The spontaneous emission in a cw rubidium diode dumped alkali laser (DPAL) system was analyzed. The fluorescence from higher lying states decreases with additional buffer gas. The intermediate states (7S, 6P, 5D) decay more slowly with buffer gas and scale super-linearly with alkali density. A detailed kinetic model has been constructed, where the dominant mechanisms are energy pooling and single photon ionization. It also includes pumping into the non-Lorentzian wings of absorption profiles, fine structure mixing, collisional de-excitation, and Penning ionization. Effects of ionization in a high powered CW rubidium DPAL were assessed.

D. C. electric field behavior of high lying states in atomic uranium

International Nuclear Information System (INIS)

Paisner, J.A.; Carlson, L.R.; Worden, E.F.; Johnson, S.A.; May, C.A.; Solarz, R.W.

1976-01-01

The effects of D. C. electric fields on high lying Rydberg and valence states in atomic uranium have been studied. Results of measurements of Stark shifts, lifetime lengthening via l-mixing, critical fields for ionization, barrier tunneling, and the appearance of zero-field parity forbidden transitions are presented for atomic uranium along with the observation of field induced autoionization of valence states. 3 figs

Going, Going, Gone: The Fate of Low-Lying Islands and Estuaries

OpenAIRE

Cairns, John

2009-01-01

Garrett Hardin s lifeboat metaphor is used to illustrate the problems of overpopulation and finite resources. Sea levels are rising due to excess atmospheric greenhouse gases that melt glaciers and warm the oceans. With anthropogenic greenhouse gas emissions continuing to increase, humankind has placed human culture and individuals at serious risk. Rising sea levels will soon make some low-lying islands uninhabitable.

Mass shift of charmonium states in p bar A collision

Science.gov (United States)

Wolf, György; Balassa, Gábor; Kovács, Péter; Zétényi, Miklós; Lee, Su Houng

2018-05-01

The masses of the low lying charmonium states, namely, the J / Ψ, Ψ (3686), and Ψ (3770) are shifted downwards due to the second order Stark effect. In p bar +Au collisions at 6-10 GeV we study their in-medium propagation. The time evolution of the spectral functions of these charmonium states is studied with a Boltzmann-Uehling-Uhlenbeck (BUU) type transport model. We show that their in-medium mass shift can be observed in the dilepton spectrum. Therefore, by observing the dileptonic decay channel of these low lying charmonium states, especially for Ψ (3686), we can gain information about the magnitude of the gluon condensate in nuclear matter. This measurement could be performed at the upcoming PANDA experiment at FAIR.

Nuclear molecular halo: the ubiquitous occurrence of van der Waals molecular states near threshold in molecular, nuclear and particle physics

International Nuclear Information System (INIS)

Gai, Moshe

1999-01-01

The observation of large E1 strength near threshold in the electromagnetic dissociation of 11 Li poses a fundamental question: Is the large E1 strength due to the threshold or is it due to a low lying E1 state? Such molecular cluster states were observed in 18 O and in several nuclei near the drip line. We discuss the nature of the threshold effect as well as review the situation in Molecular (and Particle Physics) where such Molecular States are observed near the dissociation limit. We suggest that the situation in 11 Li is reminiscent of the argon-benzene molecule where the argon atom is loosely bound by a polarization (van der Waals) mechanism and thus leads to a very extended object lying near the dissociation limit. Such states are also suggested to dominate the structure of mesons [α 0 (980), f 0 (975)] and baryons [λ(1405)] with proposed Kaon molecular structure (Dalitz) near threshold. The inspection of such states throughout Physics allows us to gain insight into this phenomenon and suggest that a new collective Molecular Dipole Degree of Freedom plays a major role in the structure of hadrons (halo nuclei, mesons and baryons), and that quantitative tools such as the E1 Molecular Sum Rule are useful for elucidating the nature of the observed low lying E1 strength in halo nuclei. (author)

Testing the tetraquark structure for the X resonances in the low-lying region

Energy Technology Data Exchange (ETDEWEB)

Kim, Hungchong [Kookmin University, Department of General Education, Seoul (Korea, Republic of); Kim, K.S. [Korea Aerospace University, School of Liberal Arts and Science, Goyang (Korea, Republic of); Cheoun, Myung-Ki [Soongsil University, Department of Physics, Seoul (Korea, Republic of); Jido, Daisuke [Tokyo Metropolitan University, Department of Physics, Hachioji, Tokyo (Japan); Oka, Makoto [Tokyo Institute of Technology, Department of Physics, Meguro (Japan); Japan Atomic Energy Agency, Advanced Science Research Center, Tokai, Ibaraki (Japan)

2016-07-15

Assuming the four-quark structure for the X resonances in the low-lying region, we calculate their masses using the color-spin interaction. Specifically, the hyperfine masses of the color-spin interaction are calculated for the possible states in spin-0, spin-1, spin-2 channels. The two states in spin-0 channel as well as the two states in spin-1 channel are diagonalized in order to generate the physical hyperfine masses. By matching the difference in hyperfine masses with the splitting in corresponding hadron masses and using the X(3872) mass as an input, we estimate the masses corresponding to the states J{sup PC} = 0{sup ++}, 1{sup +-}, 2{sup ++}. We find that the masses of two states in 1{sup +-} are close to those of X(3823), X(3900), and the mass of the 2{sup ++} state is close to that of X(3940). For them, the discrepancies are about ∝ 10 MeV. This may suggest that the quantum numbers of the controversial states are X(3823) = 1{sup +-}, X(3900) = 1{sup +-}, X(3940) = 2{sup ++}. In this work, we use the same inputs parameters, the constituent quark masses and the strength of the color-spin interaction, that have been adopted in the previous work on the D- or B-meson excited states. There, it was shown that the four-quark structure can be manifested in their excited states. Thus, our results in this work provide a consistent treatment on open- and hidden-charm mesons as far as the four-quark model is concerned. (orig.)

Low-lying (K π= 0+) states of gadolinium isotopes

Indian Academy of Sciences (India)

The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can be identified with the fully symmetric states in the sdf interacting boson approximation model. A systematic study of the sdf-IBA ...

Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability

International Nuclear Information System (INIS)

Dr. Norbert Pietralla

2006-01-01

The research project ''Nuclear Gamma-Ray Spectroscopy at the Limit of Particle Stability'' with sponsor ID ''DE-FG02-04ER41334'' started late-summer 2004 and aims at the investigation of highly excited low-spin states of selected key-nuclei in the vicinity of the particle separation threshold by means of high-resolution gamma-ray spectroscopy in electromagnetic excitation reactions. This work addresses nuclear structures with excitation energies close to the binding energy or highly excited off-yrast states in accordance with the NSAC milestones. In 2005 the program was extended towards additional use of virtual photons and theoretical description of the low-lying collective excitations in the well deformed nuclei

Fourteen international workshop on nuclear theory

International Nuclear Information System (INIS)

1995-01-01

This brochure contains the abstracts of reports delivered by 30 participants at the 14. International Workshop on Nuclear Theory organized by the Nuclear Theory Group in the Institute for Nuclear research and Nuclear Energy of the Bulgarian academy of Sciences. The main topics treated in the lectures were short-range nucleon-nucleon correlations in nuclei, relativistic scaling in nuclear matter and finite nuclei, hadron structure in chiral quark-meson theory, residual interaction strength and surface effects in the multistep reaction calculations, theoretical and experimental studies of heavy ion collisions, quantum algebraic approach to nuclear collective properties, description of low-lying states in even-even nuclei, deformed oscillator potentials, studies of solar neutrinos by I-127 detectors and gamma-ray astronomy of ultra-high energies. All reports are included in INIS separately

Dynamic polarizabilities for the low lying states of Ca+

International Nuclear Information System (INIS)

Tang, Yong-Bo; Shi, Ting-Yun; Qiao, Hao-Xue; Mitroy, J

2014-01-01

The dynamic polarizabilities of the 4s, 3d and 4p states of Ca + are calculated using a relativistic structure model. The wavelengths at which the Stark shifts between different pairs of transitions are zero are calculated. Experimental determination of the magic wavelengths could prove useful in developing better atomic structure models and in particular lead to improved values of the polarizabilities for the Ca + (3d) states

Excited state nuclear forces from the Tamm-Dancoff approximation to time-dependent density functional theory within the plane wave basis set framework

Science.gov (United States)

Hutter, Jürg

2003-03-01

An efficient formulation of time-dependent linear response density functional theory for the use within the plane wave basis set framework is presented. The method avoids the transformation of the Kohn-Sham matrix into the canonical basis and references virtual orbitals only through a projection operator. Using a Lagrangian formulation nuclear derivatives of excited state energies within the Tamm-Dancoff approximation are derived. The algorithms were implemented into a pseudo potential/plane wave code and applied to the calculation of adiabatic excitation energies, optimized geometries and vibrational frequencies of three low lying states of formaldehyde. An overall good agreement with other time-dependent density functional calculations, multireference configuration interaction calculations and experimental data was found.

Lie algebraic approach to valence bond theory of π-electron systems: a preliminary study of excited states

Science.gov (United States)

Paldus, J.; Li, X.

1992-10-01

Following a brief outline of various developments and exploitations of the unitary group approach (UGA), and its extension referred to as Clifford algebra UGA (CAUGA), in molecular electronic structure calculations, we present a summary of a recently introduced implementation of CAUGA for the valence bond (VB) method based on the Pariser-Parr-Pople (PPP)-type Hamiltonian. The existing applications of this PPP-VB approach have been limited to groundstates of various π-electron systems or, at any rate, to the lowest states of a given multiplicity. In this paper the method is applied to the low-lying excited states of several archetypal models, namely cyclobutadiene and benzene, representing antiaromatic and aromatic systems, hexatriene, representing linear polyenic systems and, finally, naphthalene, representing polyacenes.

Microscopic analysis of low-lying states in odd-A Tm isotopes

Czech Academy of Sciences Publication Activity Database

Alexa, P.; Hons, Zdeněk; Kvasil, J.

2009-01-01

Roč. 36, č. 4 (2009), 045103 /1-045103/16 ISSN 0954-3899 Institutional research plan: CEZ:AV0Z10480505 Keywords : RARE-EARTH * NUCLEI * EXCITATIONS Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 2.124, year: 2009

FMCT after South Asia's tests. A view from a nuclear-weapon state

International Nuclear Information System (INIS)

Dunn, L.A.

1998-01-01

Proposals to negotiate an international treaty to cutoff the production of plutonium and highly-enriched uranium for nuclear weapons have been on the international nuclear agenda for many decades. Hopes in the early 1990s that it would be possible finally to negotiate a FMCT, however, have not been borne out. Instead, a deadlock had ensued at the Geneva CD. It remains to be seen whether the recent nuclear tests by India and Pakistan will contribute to breaking that deadlock - or only to foreclosing any prospects for negotiating cutoff in the foreseeable future. The key lies in the attitudes of Delhi and Islamabad - influenced to the extent possible by the efforts of the international community to convince both countries' leaders to stop short of an escalating nuclear war in the region. Regardless, there are a variety of other initiatives aimed at heightening transparency and controls over the nuclear weapons materials in the five NPT nuclear weapon states that could be pursued as part of broader ongoing efforts to roll back the Cold War nuclear legacies

Collective vibrations as doorway states in the damping of nuclear motion

International Nuclear Information System (INIS)

Broglia, R.A.

1983-01-01

The damping of single-particle and giant resonances is studied. Doorway states containing low-lying surface vibrations are found to play a central role in this process. The coupling to these states lead to damping widths consistent with the empirical systematics. It is however not possible to directly relate these two quantities because of the central role played by the correlation between the particles and the hole in the vibration. (Auth.)

Nuclear structure studies at intermediate energies: Interim progress report, August 1987 through August 1988

International Nuclear Information System (INIS)

Hintz, N.M.

1988-08-01

This report contains papers on nuclear structure studies. The topics of some of the papers discussed in this report are: recoil free Δ production; low lying magnetic states; Coulomb-nuclear polarimeter; comparison of Dirac and non relativistic IA; measurements of A/sub LL/ in /rvec p//rvec p/ elastic; π + 208 Pb; /sup 206,207,208/Pb density differences; search for dibaryon resonances; and effective mass corrections to p + X

State nuclear initiatives in the United States

International Nuclear Information System (INIS)

Strauss, P.L.; Stoiber, C.R.

1977-01-01

The paper deals with State nuclear initiatives regarding the role of nuclear power in the energy future of the United States. The question of whether and under what circumstances nuclear facilities should be used to generate electricity was put to the popular vote in several States in 1976. Some general principles of Federal-State relations are discussed with specific reference to nuclear regulations. The initiative mechanism itself is described as well as its legal form and background. The parallel developments in the State and Federal legislative consideration of nuclear issues is reviewed and the suggested reasons for the defeat of the proposals in the seven States concerned are discussed. Finally, the author draws some conclusions on the effects of the 1976 initiatives on future decision-making in the US on energy policy in general and nuclear power in particular. (NEA) [fr

Quasi-Lie algebras and Lie groups

International Nuclear Information System (INIS)

Momo Bangoura

2006-07-01

In this work, we define the quasi-Poisson Lie quasigroups, dual objects to the quasi-Poisson Lie groups and we establish the correspondence between the local quasi-Poisson Lie quasigoups and quasi-Lie bialgebras (up to isomorphism). (author) [fr

Low-lying dipole response in the stable 40,48Ca nuclei within the second random-phase approximation

International Nuclear Information System (INIS)

Gambacurta, D.; Grasso, M.; Catara, F.

2012-01-01

The low-lying dipole strength distributions of 40 CaCa and 48 Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle −2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle −1 hole nature and its transition densities.

Low-lying dipole response in the stable 40,48Ca nuclei within the second random-phase approximation

Science.gov (United States)

Gambacurta, D.; Grasso, M.; Catara, F.

2012-10-01

The low-lying dipole strength distributions of 40CaCa and 48Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle -2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle -1 hole nature and its transition densities.

Combinatorial nuclear level-density model

International Nuclear Information System (INIS)

Uhrenholt, H.; Åberg, S.; Dobrowolski, A.; Døssing, Th.; Ichikawa, T.; Möller, P.

2013-01-01

A microscopic nuclear level-density model is presented. The model is a completely combinatorial (micro-canonical) model based on the folded-Yukawa single-particle potential and includes explicit treatment of pairing, rotational and vibrational states. The microscopic character of all states enables extraction of level-distribution functions with respect to pairing gaps, parity and angular momentum. The results of the model are compared to available experimental data: level spacings at neutron separation energy, data on total level-density functions from the Oslo method, cumulative level densities from low-lying discrete states, and data on parity ratios. Spherical and deformed nuclei follow basically different coupling schemes, and we focus on deformed nuclei

Theoretical study on the low-lying excited states of the phosphorus monoiodide (PI) including the spin-orbit coupling

Science.gov (United States)

Zhang, Xiaomei; Liu, Xiaoting; Liang, Guiying; Li, Rui; Xu, Haifeng; Yan, Bing

2016-01-01

The potential energy curves (PECs) of the 22 Λ-S states of the phosphorus monoiodide (PI) molecule have been calculated at the level of MRCI+Q method with correlation-consistent quadruple-ζ quality basis set. The spectroscopic constants of the bound states are determined, which well reproduce the available measurements. The metastable a1Δ state has been reported for the first time, which lies between the X3Σ- and b1Σ+ states and have much deeper well than the ground state. The R-dependent spin-orbit (SO) matrix elements are calculated with the full-electron Breit-Pauli operator. Based on the SO matrix elements, the perturbations that the 23Π state may suffer from are analyzed in detail. The SOC effect makes the original Λ-S states split into 51 Ω states. In the zero-field splitting of the ground state X3Σ-, the spin-spin coupling contribution (2.23 cm-1) is found to be much smaller compared to the spin-orbit coupling contribution (50 cm-1). The avoided crossings between the Ω states lead to much shallower potential wells and the change of dissociation relationships of the states. The Ω-state wavefunctions are analyzed depending on their Λ-S compositions, showing the strong interactions among several quasidegenerate Λ-S states of the same total SO symmetry. The transition properties including electric dipole (E1), magnetic dipole (M1), and electric quadrupole (E2) transition moments (TMs), the Franck-Condon factors, the transition probabilities and the radiative lifetimes are computed for the transitions between Ω components of a1Δ and b1Σ+ states and ground state. The transition probabilities induced by the E1, E2, and M1 transitions are evaluated. The E2 makes little effect on transition probabilities. In contrast, the E1 transition makes the main contribution to the transition probability and the M1 transition also brings the influence that cannot be neglected. Finally, the radiative lifetimes are determined with the transition moments including E

A collective model description of the low lying and giant dipole resonant properties of 40424446Ca

International Nuclear Information System (INIS)

Weise, J.I.

1982-01-01

The low-lying and giant dipole resonant properties of the even-even calcium isotopes are calculated within the framework of the Gneuss-Greiner model and compared with the experimental data. In the low energy region, comparison is also made with the predictions of a coexistence model

The group-theoretical approach to the description of nuclear states

International Nuclear Information System (INIS)

Baktybaev, K.

2001-01-01

Study of symmetrical environmental properties, including nuclei, nuclear particles, atoms and molecules has very important, and sometimes determinative meaning. The role of visible symmetry, in other words of the world beauty is generally known, and studied for a long time. The internal symmetry of material world (isotopic, angular, gauge, dynamic etc.), playing vitally important significance for its structure, creation and development has been widely studied for last years. The development of conception of dynamic symmetry and supersymmetry in the structure of nuclear system condition and their supplement under studies of specific nuclei properties is considered in the present article. The next section includes the summary of the main point of dynamic symmetry and its connection to corresponding Lie algebra and techniques of physical operators construction through generators of chosen algebra and its subalgebra. Section 3 states the dynamic-symmetric properties of atomic nuclei collective states, which are described by the model of interactive bosons. Section 4 is dedicated to conception of dynamic supersymmetry, its supplement under structure study of quasi-particle and collective states of nuclei and all interactions. In particular, the theory is applied for study of fermion and boson states in the even isotopes Pd, Dy and Er

Small reactors for low-temperature nuclear heat applications

International Nuclear Information System (INIS)

1988-06-01

In accordance with the Member States' calls for information exchange in the field of nuclear heat application (NHA) two IAEA meetings were organized already in 1976 and 1977. After this ''promising period'', the development of relevant programmes in IAEA Member States was slowed down and therefore only after several years interruption a new Technical Committee Meeting with a Workshop was organized in late 1983, to review the status of NHA, after a few new specific plans appeared in some IAEA Member States in the early 1980's for the use of heat from existing or constructed NPPs and for developing nuclear heating plants (NHP). In June 1987 an Advisory Group Meeting was convened in Winnipeg, Canada, to discuss and formulate a state-of-the-art review on ''Small Reactors for Low Temperature Nuclear Heat Application''. Information on this subject gained up to 1987 in the Member States whose experts attended this meeting is embodied in the present Technical Report. Figs and tabs

Real stabilization method for nuclear single-particle resonances

International Nuclear Information System (INIS)

Zhang Li; Zhou Shangui; Meng Jie; Zhao Enguang

2008-01-01

We develop the real stabilization method within the framework of the relativistic mean-field (RMF) model. With the self-consistent nuclear potentials from the RMF model, the real stabilization method is used to study single-particle resonant states in spherical nuclei. As examples, the energies, widths, and wave functions of low-lying neutron resonant states in 120 Sn are obtained. These results are compared with those from the scattering phase-shift method and the analytic continuation in the coupling constant approach and satisfactory agreements are found

Electromagnetic properties of low-spin states in 102,104Pd

International Nuclear Information System (INIS)

Luontama, M.; Julin, R.; Kantele, J.; Passoja, A.; Trzaska, W.; Baecklin, A.; Jonsson, N.G.; Westerberg, L.

1985-12-01

Electromagnetic transitions from low-lying 0 + , 2 + , 4 + and 3 - states in 102 , 104 Pd have been studied with (p,2n) and (p,p) reactions and with Coulomb excitation. The E2 transition probabilities from the 0 3 + state in 102 Pd (13 W.u.) and from the 0 2 + state in 104 Pd (14 W.u.) are somewhat low for two-phonon states. Generally, the E2 transition rates are reasonably well reproduced by the IBA-2 and by the boson-expansion description. The intruding 0 2 + state (tsub(1/2) = 14.3 ns) in 102 Pd is connected to the 2 2 + and 2 3 + states via strong E2 transitions: B(E2;0 2 + →2 2 + )=96+-40 W.u.; B(E2;2 3 + →0 2 + )=17+-8 W.u

Spectroscopic properties of the low-lying electronic states of RbHen (n = 1, 2) and their comparison with lighter alkali metal-helium systems

International Nuclear Information System (INIS)

Chattopadhyay, Anjan

2012-01-01

Ab initio-based configuration interaction studies on RbHe and He–Rb–He have explored some key features of the low-lying electronic states of these van der Waals systems. The radiative lifetime of the Rb*He exciplex has been calculated to be around 24.5 ns, which is slightly higher than the HeRb*He lifetime (∼20 ns) and lower than the atomic fluorescence lifetime of Rb, by roughly 3.5 ns. Better exciplex stability of the symmetric triatomic system is evidenced by its higher binding energy value in comparison to the diatomic system by a substantial margin. BSSE-corrected spin–orbit calculations of RbHe have predicted a potential barrier of the 1 2 Π 1/2 state with a height of 15 cm −1 and width of 2.57 Å. The 2 Π u state of the triatomic molecule shows a conical intersection of its Renner–Teller components (1 2 A 1 and 1 2 B 2 ) near a 99° bond angle along the bending path. Their unstable higher excited states (1 2 Σ + 1/2 or 1 2 Σ + g, 1/2 ) can trigger the pumping of the blue side of the ns 2 S 1/2 → np 2 P 3/2 transition, and this may eventually lead to the np 2 P 1/2 →ns 2 S 1/2 lasing transition. The broad fluorescence band with a peak near 11 900 cm −1 is found to arise from the 1 2 Π 3/2 –X 2 Σ + 1/2 transition of RbHe. (paper)

U(6)-phonon model of nuclear collective motion

International Nuclear Information System (INIS)

Ganev, H.G.

2015-01-01

The U(6)-phonon model of nuclear collective motion with the semi-direct product structure [HW(21)]U(6) is obtained as a hydrodynamic (macroscopic) limit of the fully microscopic proton–neutron symplectic model (PNSM) with Sp(12, R) dynamical group. The phonon structure of the [HW(21)]U(6) model enables it to simultaneously include the giant monopole and quadrupole, as well as dipole resonances and their coupling to the low-lying collective states. The U(6) intrinsic structure of the [HW(21)]U(6) model, from the other side, gives a framework for the simultaneous shell-model interpretation of the ground state band and the other excited low-lying collective bands. It follows then that the states of the whole nuclear Hilbert space which can be put into one-to-one correspondence with those of a 21-dimensional oscillator with an intrinsic (base) U(6) structure. The latter can be determined in such a way that it is compatible with the proton–neutron structure of the nucleus. The macroscopic limit of the Sp(12, R) algebra, therefore, provides a rigorous mechanism for implementing the unified model ideas of coupling the valence particles to the core collective degrees of freedom within a fully microscopic framework without introducing redundant variables or violating the Pauli principle. (author)

Using of germanium detectors in nuclear experiments with photon beams

International Nuclear Information System (INIS)

Kapitonov, I.M.; Tutin, I.A.

1995-01-01

Full text: The study of atomic nuclei with real photons is very important source of the information about nuclear structure. In such experiments the basic electromagnetic interaction between the photon and the target nuclei is well known. Experiments with photon beams become especially valuable when outcoming particles are also photons. In these cases completely model-independent information on nuclear structure can be extracted. The use of semiconductor Ge-spectrometers with excellent resolution and large sensitive volumes for recording outcoming photons gives us such an additional important advantage as possibility to observe individual closely spaced levels of the final nuclei. In the report an experience of using Ge-detectors in two types of nuclear experiments is described. Both of them - nuclear resonance fluorescence (NRF) and nuclear photodisintegration - are carried out in beams of bremsstrahlung gamma radiation. The central element of the setup recording gamma quanta in these experiments is germanium detector. NRF is unique method for studying low-lying excited nuclear states. The spins of the states can be determined easily from the measured angular distributions of scattered photons. Model independent parity assignments in NRF can be achieved by measuring polarization observables. There are two experimental possibilities: the use of linearly polarized photons (off-axis bremsstrahlung) in the entrance channel and the measurement of the linear polarization of the scattered photons using Compton polarimeters. For both methods several germanium detectors (3-5) must be used simultaneously. Nowadays Compton polarimeter can also be done from single large Ge-crystal by segmenting the outer electrode. Advantages and drawbacks of the methods and background conditions are discussed and requirements to Ge-crystals are formulated. The importance of using a new generation of electron accelerators with continuous wave (cw) beams for NRF-measurements is stressed. The

Theoretical study of the low lying states of AmO{sub 2}{sup n+}, n = 1, 2, 3

Energy Technology Data Exchange (ETDEWEB)

Notter, F.P.; Dubillard, S.; Bolvin, H. [Institut de Chimie de Strasbourg, (France)

2007-07-01

the valence space and when possible, Fock-space coupled-cluster method. For each molecule, equilibrium distance is evaluated and the spectrum of low lying excited states is calculated. Furthermore, the results are discussed in terms of ligand field theory. References [1] R. G. Denning, T.R. Snellgrove, and D.R. Woodwark. Molec. Phys., 37, 1109, (1979); [2] Z. Zhang and R.M. Pitzer. J. Phys. Chem. A, 103, 6880, (1999); [3] S. Matsika and R.M. Pitzer. J. Phys. Chem. A, 105, 637, (2001); [4] C. Clavaguera-Sarrio, V. Vallet, D. Maynau, and C.J. Marsden. J. Chem. Phys., 123, 204309, (2005); [5] L. Gagliardi, B.O. Roos, P.A. Malmqvist, and J. M. Dyke. J. Phys. Chem. A, 105, 10602, (2001); [6] S. Matsika and R. M. Pitzer. J. Phys. Chem. A, 104, 4064, (2000); [7] L. Maron, T. Leininger, B. Schimmelpfennig, V. Vallet, J.L. Heully, C. Teichtel, O. Gropen, and U. Wahlgren. Chem. Phys., 244, 195, (1999); [8] C. Clavaguera-Sarrio, V. Vallet, D. Maynau, and C.J. Marsden. J. Chem. Phys., 121, 5312, (2004); [9] I. Invante, A. Severo Perera Gomes, and L. Visscher. J. Chem. Phys., 125, 074301, (2006)

Low-lying dipole response in the stable {sup 40,48}Ca nuclei within the second random-phase approximation

Energy Technology Data Exchange (ETDEWEB)

Gambacurta, D.; Grasso, M.; Catara, F. [GANIL,CEA/DSM-CNRS/IN2P3, Caen (France); Institut de Physique Nucleaire, Universite Paris-Sud, IN2P3-CNRS, F-91406 Orsay Cedex (France); Dipartimento di Fisica e Astronomia dell' Universita di and INFN Catania (Italy)

2012-10-20

The low-lying dipole strength distributions of {sup 40}CaCa and {sup 48}Ca, in the energy region between 5 and 10 MeV, are studied within the second random phase approximation (RPA) with Skyrme interaction. Standard RPA models do not usually predict any presence of strength in this energy region, while experimentally a significant amount of strength is found. The inclusion of the 2 particle -2 hole configurations allows to obtain a description in a rather good agreement with the experimental data. The properties of the most collective state are analyzed in terms of its 1 particle -1 hole nature and its transition densities.

Earthquakes - a danger to deep-lying repositories?; erdbeben: eine gefahr fuer tiefenlager?

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-03-15

This booklet issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at geological factors concerning earthquakes and the safety of deep-lying repositories for nuclear waste. The geological processes involved in the occurrence of earthquakes are briefly looked at and the definitions for magnitude and intensity of earthquakes are discussed. Examples of damage caused by earthquakes are given. The earthquake situation in Switzerland is looked at and the effects of earthquakes on sub-surface structures and deep-lying repositories are discussed. Finally, the ideas proposed for deep-lying geological repositories for nuclear wastes are discussed.

Low-lying (K π= 0+) states of gadolinium isotopes

Indian Academy of Sciences (India)

The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science

TDHF and fluid dynamics of nuclear collective motions

International Nuclear Information System (INIS)

Di Nardo, M.; Di Toro, M.; Giansiracusa, G.; Lombardo, U.; Russo, G.

1983-01-01

The nuclear fluid dynamical equations are derived from a mean field description of the nuclear dynamics. Simple approximate solutions, corresponding to generalized scaling modes, are worked out for rotations and vibrations, with the evaluation of inertial parameters and flow patterns. Giant resonances are shown to be quite well described within an irrotational ansatz, which is equivalent to a lowest multipoles (up to lsub(max)=2) distortion of the momentum distribution. The physical meaning of a higher order truncation of the TDHF-Fluid-Dynamics chain is finally discussed with its implication on low lying states and on some description of the Landau damping. (author)

Classification and identification of Lie algebras

CERN Document Server

Snobl, Libor

2014-01-01

The purpose of this book is to serve as a tool for researchers and practitioners who apply Lie algebras and Lie groups to solve problems arising in science and engineering. The authors address the problem of expressing a Lie algebra obtained in some arbitrary basis in a more suitable basis in which all essential features of the Lie algebra are directly visible. This includes algorithms accomplishing decomposition into a direct sum, identification of the radical and the Levi decomposition, and the computation of the nilradical and of the Casimir invariants. Examples are given for each algorithm. For low-dimensional Lie algebras this makes it possible to identify the given Lie algebra completely. The authors provide a representative list of all Lie algebras of dimension less or equal to 6 together with their important properties, including their Casimir invariants. The list is ordered in a way to make identification easy, using only basis independent properties of the Lie algebras. They also describe certain cl...

A novel experimental technique of nuclear lifetime measurements

International Nuclear Information System (INIS)

Yuminov, O.A.; D'Arrigo, A.; Giardina, G.; Taccone, A.; Vannini, G.; Moroni, A.; Ricci, R.A.; Vannucci, L.

1995-01-01

In the present paper a new experimental method to measure nuclear reaction time in the 10 -15 -10 -10 s region is presented. Measurements of the lifetimes of low-lying and long-lived states of 19 F and 20 Ne decaying via α-channel were carried out with the aim of checking the feasibility of the method. The results obtained in this way are compared with the lifetimes known from different techniques. ((orig.))

Novel Solution for Low-Lying Land Areas Safe from Natural Hazards—Toward Reconstruction of Lost Coastal Areas in Northeast Japan

Directory of Open Access Journals (Sweden)

Toshio Nakajima

2015-07-01

Full Text Available The imminent fear of water-related hazards such as flooding hangs over low-lying areas, in particular now because climate changes have led to increased hazards, like storm surges, that could result in serious harm. This paper aims to provide a novel solution—namely “the floating platform”—that can transform dangerous low-lying areas into those safeguarded against potential hazards. Additionally, by utilizing this solution as a secure base for society to build atop this new artificial reservoir, we offer a better future role for such areas. Meanwhile, we propose adoption of our concept soon at two low-lying areas in northeast Japan hard-hit by the huge 11 March 2011 tsunami: Sendai’s Arahama coastal district and the still-devastated residential harbor area of Kesennuma, both cities in need of a fresh perspective.

Theoretical description of high-lying two-electrons states

International Nuclear Information System (INIS)

Greene, C.H.; Cavagnero, M.; Sadeghpour, H.R.

1993-01-01

Within the past two years, experiments on high-lying doubly-excited states in He and H- have shown spectra at energies near excited hydrogenic thresholds having principal quantum numbers in the range N=5--9. While they display some nontrivial complexities, the spectra are tremendously simpler than might be anticipated on the basis of independent electron models, in that only a small fraction of the total number of anticipated resonances are observed experimentally. Moreover, for principal quantum number N that are not too high, specifically N - , the resonance positions are described accurately by adiabatic calculations using hyperspherical coordinates and can be parametrized by a remarkably simple two-electron Rydberg formula. The observed propensity for excitation of only a small subset of the possible resonance states has been codified by several groups into approximate selection rules based on alternative (but apparently equivalent) classification schemes. Comparatively few attempts have been made at quantitative tests of the validity of these rules. The present review describes recent efforts to quantify their accuracy and limitations using R-matrix and quantum defect techniques, and Smith's delay-time matrix. Prospensity rules for exciting different degrees of freedom are found to differ greatly in their degree of validity

Towards a shell-model description of intruder states and the onset of deformation

International Nuclear Information System (INIS)

Heyde, K.; Van Isacker, P.; Casten, R.F.; Wood, J.L.

1985-01-01

Basing on the nuclear shell-model and concentrating on the monopole, pairing and quadrupole corrections originating from the nucleon-nucleon force, both the appearance of low-lying 0 + intruder states near major closed shells (Z = 50, 82) and sub-shell regions (Z = 40, 64) can be described. Moreover, a number of new facets related to the study of intruder states are presented. 19 refs., 3 figs

Lie groups and Lie algebras for physicists

CERN Document Server

Das, Ashok

2015-01-01

The book is intended for graduate students of theoretical physics (with a background in quantum mechanics) as well as researchers interested in applications of Lie group theory and Lie algebras in physics. The emphasis is on the inter-relations of representation theories of Lie groups and the corresponding Lie algebras.

FMCT after South Asia's tests. A view from a nuclear-weapon state

Energy Technology Data Exchange (ETDEWEB)

Dunn, L.A. [Science Applications Int. Corp. (United States)

1998-07-01

Proposals to negotiate an international treaty to cutoff the production of plutonium and highly-enriched uranium for nuclear weapons have been on the international nuclear agenda for many decades. Hopes in the early 1990s that it would be possible finally to negotiate a FMCT, however, have not been borne out. Instead, a deadlock had ensued at the Geneva CD. It remains to be seen whether the recent nuclear tests by India and Pakistan will contribute to breaking that deadlock - or only to foreclosing any prospects for negotiating cutoff in the foreseeable future. The key lies in the attitudes of Delhi and Islamabad - influenced to the extent possible by the efforts of the international community to convince both countries' leaders to stop short of an escalating nuclear war in the region. Regardless, there are a variety of other initiatives aimed at heightening transparency and controls over the nuclear weapons materials in the five NPT nuclear weapon states that could be pursued as part of broader ongoing efforts to roll back the Cold War nuclear legacies.

Nuclear orientation experiments concerning odd-A gold isotopes

International Nuclear Information System (INIS)

Ligthart, H.J.

1982-01-01

This thesis describes nuclear spectroscopy aspects of nuclear orientation in the odd-A gold isotopes 191 Au, 193 Au, 195 Au and 197 Au. These isotopes lie in a transitional region between the spherical nuclei in the lead region and the strongly deformed rare earth isotopes. Following a general introduction to nuclear orientation, the experimental arrangement is described. A new technique is presented that applies in-beam recoil implantation inside the refrigerator itself and this was applied to the case of 191 Au. The three other gold isotopes were oriented using a conventional dilution refrigerator. The nuclear orientation experiments concerning 11/2 - isomers of the isotopes are described. The long-lived isomeric states were oriented using the large hyperfine field of gold in iron. Higher lying levels were studied by nuclear orientation of the Hg parent states. (Auth./C.F.)

Nuclear hadrodynamics

International Nuclear Information System (INIS)

Geesaman, D.F.

1984-01-01

The role of hadron dynamics in the nucleus is illustrated to show the importance of nuclear medium effects in hadron interactions. The low lying hadron spectrum is considered to provide the natural collective variables for nuclear systems. Recent studies of nucleon-nucleon and delta-nucleon interactions are reviewed, with emphasis on the type of experimental phenomena which signal the importance of the many-body dynamics. 28 references

Rydberg phases of Hydrogen and low energy nuclear reactions

Science.gov (United States)

Olafsson, Sveinn; Holmlid, Leif

2016-03-01

For over the last 26 years the science of cold fusion/LENR has been researched around the world with slow pace of progress. Modest quantity of excess heat and signatures of nuclear transmutation and helium production have been confirmed in experiments and theoretical work has only resulted in a large flora of inadequate theoretical scenarios. Here we review current state of research in Rydberg matter of Hydrogen that is showing strong signature of nuclear processes. In the presentation experimental behavior of Rydberg matter of hydrogen is described. An extensive collaboration effort of surface physics, catalysis, atomic physics, solid state physics, nuclear physics and quantum information is need to tackle the surprising experimental results that have so far been obtained. Rydberg matter of Hydrogen is the only known state of matter that is able to bring huge collection of protons to so short distances and for so long time that tunneling becomes a reasonable process for making low energy nuclear reactions. Nuclear quantum entanglement can also become realistic process at theses conditions.

Microscopic study of low-lying yrast spectra and deformation systematics of even-even barium isotopes

International Nuclear Information System (INIS)

Sarswat, S.P.; Bharti, Arun; Khosa, S.K.

1996-01-01

The yrast spectra has been obtained in the variation-after-projection framework using pairing-plus-quadrupole- quadrupole model for the two body interaction. Besides the low-lying yrast spectra, the calculated values of intrinsic quadrupole moments of some of the barium isotopes i.e. 124-134 Ba are presented

Ground state correlations and structure of odd spherical nuclei

International Nuclear Information System (INIS)

Mishev, S.; Voronov, V.V.

2008-01-01

It is well known that the Pauli principle plays a substantial role at low energies because the phonon operators are not ideal boson operators. Calculating the exact commutators between the quasiparticle and phonon operators one can take into account the Pauli principle corrections. Besides, the ground state correlations due to the quasiparticle interaction in the ground state influence the single-particle fragmentation as well. In this paper, we generalize the basic equations of the quasiparticle-phonon nuclear model to account for both effects mentioned. As an illustration of our approach, calculations on the structure of the low-lying states in 133 Ba have been performed

Study of the high lying states of 12C by inelastic scattering of hadrons

International Nuclear Information System (INIS)

Buenerd, M.; Martin, P.; Saintignon, P. de; Loiseaux, J.-M.

1977-03-01

Beams of 45MeV and 155MeV protons and 60MeV alphas have been used to investigate the high lying continuum of 12 C. Various multipolarities and strengths have been located between 15MeV and 30MeV excitation energy. Isovector E1 states have been located at excitation energies between 20 and 30MeV; E2 states at 15.3, 18.4MeV (T=0); E3 state at 21.65MeV (T=0); E4 state at 19.6MeV (T=0); M2 state at 19.2MeV (T=1). The results are analyzed in terms of both collective and microscopic model calculations

Recent applications of nuclear orientation to solid state physics

International Nuclear Information System (INIS)

Turrell, B.G.

1985-01-01

The author reviews how certain problems in solid state physics have been clarified by low temperature nuclear orientation and nuclear magnetic resonance of oriented nuclei. The advantages of these techniques, a brief survey of recent progress in traditional applications, and new developments are discussed, and, finally, future trends are suggested. (Auth.)

1989 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites: National Low-Level Waste Management Program

International Nuclear Information System (INIS)

Fuchs, R.L.; Culbertson-Arendts, K.

1990-12-01

The National Low-Level Waste Management Program has published eleven annual state-by-state assessment reports. These reports provide both national and state-specific disposal data on low-level radioactive wastes. Data in this report are divided into generator category, waste class, volume, and activity. Included in this report are tables showing a distribution of wastes by state for 1989 and a comparison of waste volumes by state for 1985 through 1989; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1989. In this year's report, a distinction has been made between low-level radioactive waste shipped directly for disposal by generators and that handled by an intermediary. 7 refs., 4 tabs

Theoretical studies of multistep processes, isospin effects in nuclear scattering, and meson and baryon interactions in nuclear physics: Annual progess report, 1 May 1988--30 April 1989

International Nuclear Information System (INIS)

Landau, R.H.; Madsen, V.A.

1988-01-01

A progress report is presented for DOE grant FG06-86ER40283 supporting theoretical studies in nuclear and particle physics at Oregon State University. The research was led by Professors Landau and Madsen, and carried out in collaboration with graduate students in Corvallis, and scientists at LLNL-Livermore, TRIUMF, KFA-Juelich, Purdue University, and Florida State University. The studies include meson-exchange-current effects, quark effects, and relativistic (Dirac) effects deduced from spin observables in p- 3 He scattering, atomic and nuclear Gamow states in momentum space of kaons and antiprotons, and charge-symmetry violation in pion scattering. Additional studies include microscopic optical potential calculations, multiple step processes, and differences in neutron and proton multipole matrix elements and transition densities in low lying collective states and in giant resonances. 13 refs

On Deformations and Contractions of Lie Algebras

Directory of Open Access Journals (Sweden)

Marc de Montigny

2006-05-01

Full Text Available In this contributed presentation, we discuss and compare the mutually opposite procedures of deformations and contractions of Lie algebras. We suggest that with appropriate combinations of both procedures one may construct new Lie algebras. We first discuss low-dimensional Lie algebras and illustrate thereby that whereas for every contraction there exists a reverse deformation, the converse is not true in general. Also we note that some Lie algebras belonging to parameterized families are singled out by the irreversibility of deformations and contractions. After reminding that global deformations of the Witt, Virasoro, and affine Kac-Moody algebras allow one to retrieve Lie algebras of Krichever-Novikov type, we contract the latter to find new infinite dimensional Lie algebras.

Theoretical study of the lowest-lying electronic states of Aluminium monoiodide

International Nuclear Information System (INIS)

Taher, F.; Kabbani, A.; Ani-El Houte, W.

2004-01-01

Full text.The spectroscopic study of Aluminium monohalides, especially the Aluminium monoiodide, is important for monitoring such species in high temperature fast-flow reactors. Theoretical calculations of AlI are not available, whereas several studies have been done for the other aluminium monohalides. In this work, CAS-SCF/MRCI calculations are performed for the lowest-lying electronic states of AlI in a range of internuclear distance between 2.30 A and 2.80 A. Ab-initio calculations have been effectuated by using the computational chemistry program Molpro. The basis set used in this study for aluminium atom is that used by Langhoff for aluminium monohalides, of contractions using atomic natural orbitals and a pseudopotential is used for iode. Accurate theoretical spectroscopic constants and potential curves are obtained for the ground state X 1 Σ + and the first excited states a 3 Π and A 1 Π. The calculated values of Te, ωe, ωexe and re of these states are compatible with the experimental results. An ordering of states is represented for the lowest five predicted singlet and lowest five predicted triplet states. These results provide a big support to determine the analogy in the ordering of the electronic states in AlF, AlBr and AlI respectively at lower energies. These theoretical results identify a set of electronic singlet and triplet states unobserved experimentally

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

Lying to patients with dementia: Attitudes versus behaviours in nurses.

Science.gov (United States)

Cantone, Daniela; Attena, Francesco; Cerrone, Sabrina; Fabozzi, Antonio; Rossiello, Riccardo; Spagnoli, Laura; Pelullo, Concetta Paola

2017-01-01

Using lies, in dementia care, reveals a common practice far beyond the diagnosis and prognosis, extending to the entire care process. In this article, we report results about the attitude and the behaviour of nurses towards the use of lies to patients with dementia. An epidemiological cross-sectional study was conducted between September 2016 and February 2017 in 12 elderly residential facilities and in the geriatric, psychiatric and neurological wards of six specialised hospitals of Italy's Campania Region. In all, 106 nurses compiled an attitude questionnaire (A) where the main question was 'Do you think it is ethically acceptable to use lies to patients with dementia?', instead 106 nurses compiled a behaviour questionnaire (B), where the main question was 'Have you ever used lies to patients with dementia?' Ethical considerations: Using lies in dementia care, although topic ethically still controversial, reveals a common practice far beyond the diagnosis and prognosis, extending to the entire care process. Only a small percentage of the interviewed nurses stated that they never used lies/that it is never acceptable to use lies (behaviour 10.4% and attitude 12.3%; p = 0.66). The situation in which nurses were more oriented to use lies was 'to prevent or reduce aggressive behaviors'. Indeed, only the 6.7% in the attitude group and 3.8% in the behaviour group were against using lies. On the contrary, the case in which the nurses were less oriented to use lies was 'to avoid wasting time giving explanations', in this situation were against using lies the 51.0% of the behaviour group and the 44.6% of the attitude group. Our results, according to other studies, support the hypothesis of a low propensity of nurses to ethical reflection about use of lies. In our country, the implementation of guidelines about a correct use of lie in the relationship between health operators and patients would be desirable.

Lie Quasi-Bialgebras and Cohomology of Lie algebra

International Nuclear Information System (INIS)

Bangoura, Momo

2010-05-01

Lie quasi-bialgebras are natural generalisations of Lie bialgebras introduced by Drinfeld. To any Lie quasi-bialgebra structure of finite-dimensional (G, μ, γ, φ), corresponds one Lie algebra structure on D = G + G*, called the double of the given Lie quasi-bialgebra. We show that there exist on ΛG, the exterior algebra of G, a D-module structure and we establish an isomorphism of D-modules between ΛD and End(ΛG), D acting on ΛD by the adjoint action. (author) [fr

Variational Monte Carlo calculations of nuclear ground states

International Nuclear Information System (INIS)

Wiringa, R.B.

1990-01-01

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 nucleons. We start with realistic nucleon-nucleon potentials, supplemented with consistent three-nucleon potentials and two-body electroweak current operators, and try to predict nuclear ground properties, such as the binding energy, density and momentum distributions, and electromagnetic form factors. We also seek to predict other properties of nuclei such as excited states and low-energy reactions. 21 refs., 14 figs., 5 tabs

Influence of the Pauli principle on the one-quasiparticle states in odd spherical nuclei

International Nuclear Information System (INIS)

Chan Zuy Khuong

1980-01-01

The effect of the Pauli principle on the fragmentation of one-quasiparticle states in odd spherical nuclei is studied within the quasiparticle-phonon nuclear model. It is shown that the Pauli principle influences considerably the position and structure of a few low-lying states. The fragmentation of one-quasiparticle states at intermediate and high excitation energies is slightly affected by the Pauli principle, and the calculations can be performed by taking the Pauli principle into account roughly. (author)

Constraining nuclear photon strength functions by the decay properties of photo-excited states

Science.gov (United States)

Isaak, J.; Savran, D.; Krtička, M.; Ahmed, M. W.; Beller, J.; Fiori, E.; Glorius, J.; Kelley, J. H.; Löher, B.; Pietralla, N.; Romig, C.; Rusev, G.; Scheck, M.; Schnorrenberger, L.; Silva, J.; Sonnabend, K.; Tonchev, A. P.; Tornow, W.; Weller, H. R.; Zweidinger, M.

2013-12-01

A new approach for constraining the low-energy part of the electric dipole Photon Strength Function (E1-PSF) is presented. Experiments at the Darmstadt High-Intensity Photon Setup and the High Intensity γ→-Ray Source have been performed to investigate the decay properties of 130Te between 5.50 and 8.15 MeV excitation energy. In particular, the average γ-ray branching ratio to the ground state and the population intensity of low-lying excited states have been studied. A comparison to the statistical model shows that the latter is sensitive to the low-energy behavior of the E1-PSF, while the average ground state branching ratio cannot be described by the statistical model in the energy range between 5.5 and 6.5 MeV.

Compatible Lie Bialgebras

International Nuclear Information System (INIS)

Wu Ming-Zhong; Bai Cheng-Ming

2015-01-01

A compatible Lie algebra is a pair of Lie algebras such that any linear combination of the two Lie brackets is a Lie bracket. We construct a bialgebra theory of compatible Lie algebras as an analogue of a Lie bialgebra. They can also be regarded as a “compatible version” of Lie bialgebras, that is, a pair of Lie bialgebras such that any linear combination of the two Lie bialgebras is still a Lie bialgebra. Many properties of compatible Lie bialgebras as the “compatible version” of the corresponding properties of Lie bialgebras are presented. In particular, there is a coboundary compatible Lie bialgebra theory with a construction from the classical Yang–Baxter equation in compatible Lie algebras as a combination of two classical Yang–Baxter equations in Lie algebras. Furthermore, a notion of compatible pre-Lie algebra is introduced with an interpretation of its close relation with the classical Yang–Baxter equation in compatible Lie algebras which leads to a construction of the solutions of the latter. As a byproduct, the compatible Lie bialgebras fit into the framework to construct non-constant solutions of the classical Yang–Baxter equation given by Golubchik and Sokolov. (paper)

Lie groups, lie algebras, and representations an elementary introduction

CERN Document Server

Hall, Brian

2015-01-01

This textbook treats Lie groups, Lie algebras and their representations in an elementary but fully rigorous fashion requiring minimal prerequisites. In particular, the theory of matrix Lie groups and their Lie algebras is developed using only linear algebra, and more motivation and intuition for proofs is provided than in most classic texts on the subject. In addition to its accessible treatment of the basic theory of Lie groups and Lie algebras, the book is also noteworthy for including: a treatment of the Baker–Campbell–Hausdorff formula and its use in place of the Frobenius theorem to establish deeper results about the relationship between Lie groups and Lie algebras motivation for the machinery of roots, weights and the Weyl group via a concrete and detailed exposition of the representation theory of sl(3;C) an unconventional definition of semisimplicity that allows for a rapid development of the structure theory of semisimple Lie algebras a self-contained construction of the representations of compac...

Calculation of nuclear level density parameters of some light deformed medical radionuclides using collective excitation modes of observed nuclear spectra

International Nuclear Information System (INIS)

Okuducu, S.; Sarac, H.; Akti, N. N.; Boeluekdemir, M. H.; Tel, E.

2010-01-01

In this study the nuclear energy level density based on nuclear collective excitation mechanism has been identified in terms of the low-lying collective level bands at near the neutron binding energy. Nuclear level density parameters of some light deformed medical radionuclides used widely in medical applications have been calculated by using different collective excitation modes of observed nuclear spectra. The calculated parameters have been used successfully in estimation of the neutron-capture cross section basic data for the production of new medical radionuclides. The investigated radionuclides have been considered in the region of mass number 40< A< 100. The method used in the present work assumes equidistance spacing of the collective coupled state bands of the interest radionuclides. The present calculated results have been compared with the compiled values from the literatures for s-wave neutron resonance data.

Observation of a low-lying neutron-unbound state in 19C

International Nuclear Information System (INIS)

Thoennessen, M.; Mosby, S.; Badger, N.S.; Baumann, T.; Bazin, D.; Bennett, M.; Brown, J.; Christian, G.; DeYoung, P.A.; Finck, J.E.; Gardner, M.; Hook, E.A.; Luther, B.; Meyer, D.A.; Mosby, M.; Rogers, W.F.

2013-01-01

Proton removal reactions from a secondary 22 N beam were utilized to populate unbound states in neutron-rich carbon isotopes. Neutrons were measured with the Modular Neutron Array (MoNA) in coincidence with carbon fragments. A resonance with a decay energy of 76(14) keV was observed in the system 18 C+n corresponding to a state in 19 C at an excitation energy of 653(95) keV. This resonance could correspond to the first 5/2 + state which was recently speculated to be unbound in order to describe 1n and 2n removal cross section measurements from 20 C

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.

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.

Effect translational invariance in low-lying electric dipole excitations in 236U and 238U

International Nuclear Information System (INIS)

Ertugral, F.

2005-01-01

In this paper the translational invariant QRPA approach suggested by Pyatov [1] for the spherical nuclei has been extended to describe the 1 - states in deformed nuclei. The role of spurious centre-of-motion state on the Pygmy dipole resonance (PDR) has been investigated in the deformed 236 U and 238 U nuclei. It has been shown that the effect of taking into account the translational invariance of the Hamiltonians in the QRPA with separation of zero energy spurious solutions are noticeable in both the low energy density of 1 - states and in the PDR. Present investigation demonstrates the advantage of the translational invariant QRPA over the non translational invariant one. Within the translational invariant model the effect of removing spurious states on the E1 strength distribution is stronger than in none invariant QRPA (∼20%) for the states up to the neutron binding energy. It is found that the spurious state is spread over many levels, the largest admixture being situated in the region of the energy spacing between nuclear shells o w h . The giant resonance states contain, as a rule, very small admixtures of the spurious state

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

Low-lying eigenmodes of the Wilson-Dirac operator and correlations with topological objects

International Nuclear Information System (INIS)

Kusterer, Daniel-Jens; Hedditch, John; Kamleh, Waseem; Leinweber, D.B.; Williams, Anthony G.

2002-01-01

The probability density of low-lying eigenvectors of the hermitian Wilson-Dirac operator H(κ)=γ 5 D W (κ) is examined. Comparisons in position and size between eigenvectors, topological charge and action density are made. We do this for standard Monte-Carlo generated SU(3) background fields and for single instanton background fields. Both hot and cooled SU(3) background fields are considered. An instanton model is fitted to eigenmodes and topological charge density and the sizes and positions of these are compared

Proceedings of the symposium on nuclear physics: Invited talks/Seminars. Vol. 34A(1991)

International Nuclear Information System (INIS)

Kailas, S.; Singh, P.

1992-01-01

The proceedings volume contains the invited talks delivered at the Symposium on Nuclear Physics held at Bombay during 26-30 December 1991. These talks dealt with the some of the front line areas of nuclear physics. They are: influence of nuclear dynamics on measurements of the fission fragment angular distribution in heavy ion induced fusion-fission reactions, stability of hot nuclei formed in violent nuclear collisions limited mainly by temperature, resonant behaviour in heavy ion reactions and the structural connection of high-lying states with the specific low-lying states initiated through particle decay, co-existence of different shapes in the same nuclei, evidence for deformed nucleons, pre-fission measurements in heavy ion induced fusion-fission experiments and influence of these neutrons in slowing down fission process, leptodermous expansion techniques for explaining various physical properties of nuclei, and giant resonances in hot rotating nuclei. Two seminars were also held in the symposium. One was on heavy ion reactions below and near the Coulomb barrier and the other one was on quark-gluon plasma. The papers presented at these seminars are also included in the book. The above mentioned invited talks and seminar papers have been processed separately for inclusion in the INIS Database. (N.B.)

Enhancement mechanisms of low energy nuclear reactions

Energy Technology Data Exchange (ETDEWEB)

Gareev, F. A.; Zhidkova, I.E.; Ratis, Yu.L. [Joint Institute for Nuclear Research, JINR, 6 Joliot Curie Street, Dubna, Moscow Region 141980 (Russian Federation)

2006-07-01

The full review of Russian low energy nuclear reactors is represented. We have concluded that transmutation of nuclei at low energies, LENR, is possible in the framework of the modern physical theory - excitation and ionization of atoms and universal resonance synchronization principle are responsible for it. Investigation of this phenomenon requires knowledge of different branches of science: nuclear and atomic physics, chemistry and electrochemistry, condensed matter and solid state physics. The results of this research field can provide a new source of energy, substances and technologies. The puzzle of poor reproducibility of experimental data is due to the fact that LENR occurs in open systems and it is extremely sensitive to parameters of external fields and systems. Classical reproducibility principle should be reconsidered for LENR experiments. Poor reproducibility and unexplained results do not means that the experiment is wrong.

Enhancement mechanisms of low energy nuclear reactions

International Nuclear Information System (INIS)

Gareev, F. A.; Zhidkova, I.E.; Ratis, Yu.L.

2006-01-01

The full review of Russian low energy nuclear reactors is represented. We have concluded that transmutation of nuclei at low energies, LENR, is possible in the framework of the modern physical theory - excitation and ionization of atoms and universal resonance synchronization principle are responsible for it. Investigation of this phenomenon requires knowledge of different branches of science: nuclear and atomic physics, chemistry and electrochemistry, condensed matter and solid state physics. The results of this research field can provide a new source of energy, substances and technologies. The puzzle of poor reproducibility of experimental data is due to the fact that LENR occurs in open systems and it is extremely sensitive to parameters of external fields and systems. Classical reproducibility principle should be reconsidered for LENR experiments. Poor reproducibility and unexplained results do not means that the experiment is wrong

State and Federal activities on low-level waste

International Nuclear Information System (INIS)

1983-01-01

With the passage of the Low-Level Waste Policy Act in December 1980, the states have assumed the management responsibility and the federal government has become a facilitator. State and Federal roles in regulation have not altered. This paper reviews the developments over the last two years to point out the progress made and critical steps that lie ahead. Both technological and political aspects are covered, and a conclusion is presented with a look to the future. Since compact development in the tool chosen by the politicans for low-level waste management, the author reviews the present status starting with the northwest compact which has been introduced into the House and Senate and is subject to hearings. The past two years have seen real progress in technology in the broadest sense. An information development and dissemination system was established in 1978 wih the state-by-state assessment of low-level waste disposal. Annual examinations have been made through 1981 which enables one to understand the generation of low-level wastes. Policy level planning by states can be supported by the base level of information available. Incineration of dry active waste and other non-fuel cycle waste is ready to be fully accepted. Much work has been done on volume reduction of liquids. The increased understanding of the ways to make a disposal site work represents a major technolological improvement. Within the DOE system, there is beginning to be a real understanding of the critical parameters in disposal site performance in the East

Lie algebras

CERN Document Server

Jacobson, Nathan

1979-01-01

Lie group theory, developed by M. Sophus Lie in the 19th century, ranks among the more important developments in modern mathematics. Lie algebras comprise a significant part of Lie group theory and are being actively studied today. This book, by Professor Nathan Jacobson of Yale, is the definitive treatment of the subject and can be used as a textbook for graduate courses.Chapter I introduces basic concepts that are necessary for an understanding of structure theory, while the following three chapters present the theory itself: solvable and nilpotent Lie algebras, Carlan's criterion and its

Introducing nuclear power into currently non-nuclear states

International Nuclear Information System (INIS)

Claassen, Gert

2007-01-01

As the nuclear renaissance gains momentum, many countries that currently have no nuclear power plants will begin to consider introducing them. It is anticipated that smaller reactors such as the Pebble Bed Modulator Reactor (PBMR) will not only be sold to current nuclear states to also to states where there is currently no nuclear experience. A range of issues would have to be considered for nuclear plants to be solid to non-nuclear states, such as the appropriate regulatory environment, standardization and codes, non-proliferation, security of supply, obtaining experienced merchant operators, appropriate financial structures and education and training. The paper considers nine major issues that need to be addressed by governments and vendors alike. International cooperation by organisations such as the IAEA, financial institutions and international suppliers will be required to ensure that developing countries as well as developed ones share the benefits of the nuclear renaissance. The opportunities that the nuclear industry affords to develop local skills, create job opportunities and to develop local manufacturing industries are among the important reasons that the South African Government has decided to support and fund the development of the Pebble Bed Modular Reactor project. These considerations are included in the paper. (author)

The effect of the Pauli principle on the fragmentation of one-quasiparticle states in spherical nuclei

International Nuclear Information System (INIS)

Khuong, C.Z.; Soloviev, V.G.; Voronov, V.V.

1981-01-01

The effect of the Pauli principle on the fragmentation of one-quasiparticle states in spherical nuclei is studied within the quasiparticle-phonon nuclear model. It is shown that the Pauli principle influences considerably the position and structure of a few low-lying states, the fragmentation of one-quasiparticle states at intermediate and high excitation energies is slightly affected by the Pauli principle, and the calculations can be performed by taking the Pauli principle roughly into account. (author)

Nuclear reactions video (knowledge base on low energy nuclear physics)

International Nuclear Information System (INIS)

Zagrebaev, V.; Kozhin, A.

1999-01-01

The NRV (nuclear reactions video) is an open and permanently extended global system of management and graphical representation of nuclear data and video-graphic computer simulation of low energy nuclear dynamics. It consists of a complete and renewed nuclear database and well known theoretical models of low energy nuclear reactions altogether forming the 'low energy nuclear knowledge base'. The NRV solves two main problems: 1) fast and visualized obtaining and processing experimental data on nuclear structure and nuclear reactions; 2) possibility for any inexperienced user to analyze experimental data within reliable commonly used models of nuclear dynamics. The system is based on the realization of the following principal things: the net and code compatibility with the main existing nuclear databases; maximal simplicity in handling: extended menu, friendly graphical interface, hypertext description of the models, and so on; maximal visualization of input data, dynamics of studied processes and final results by means of real three-dimensional images, plots, tables and formulas and a three-dimensional animation. All the codes are composed as the real Windows applications and work under Windows 95/NT

1995 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

Energy Technology Data Exchange (ETDEWEB)

Fuchs, R.L.

1996-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in US. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included are tables showing the distribution of waste by state for 1995 and a comparison of waste volumes and radioactivity by state for 1991 through 1995; also included is a list of all commercial nuclear power reactors in US as of Dec. 31, 1994. This report distinguishes low-level radioactive waste shipped directly for disposal by generators and waste handled by an intermediary.

New development of the projected shell model and description of low-lying collective states in transitional nuclei

International Nuclear Information System (INIS)

Chen, F. Q.; Sun, Y.

2013-01-01

Description of the interplay between different nuclear shapes is an interesting but challenging problem. The original projected shell model (PSM) is applicable to nuclei with fixed shapes. We extend the PSM by superimposing (angular-momentum- and particle-number-) projected product wave functions in the spirit of the generate coordinate method. With this development, the Gd isotopes across the N = 90 region are studied, and the results indicate spectroscopic features of shape phase transition with varying neutron number. In order to illustrate the shape distribution in microscopic wave functions, we introduce a deformation representation and show that the collectively excited K π = 0 + states in the Gd isotopes have characters of shape vibration. (authors)

The Lie algebra of the N=2-string

International Nuclear Information System (INIS)

Kugel, K.

2006-01-01

The theory of generalized Kac-Moody algebras is a generalization of the theory of finite dimensional simple Lie algebras. The physical states of some compactified strings give realizations of generalized Kac-Moody algebras. For example the physical states of a bosonic string moving on a 26 dimensional torus form a generalized Kac-Moody algebra and the physical states of a N=1 string moving on a 10 dimensional torus form a generalized Kac-Moody superalgebra. A natural question is whether the physical states of the compactified N=2-string also realize such an algebra. In this thesis we construct the Lie algebra of the compactified N=2-string, study its properties and show that it is not a generalized Kac-Moody algebra. The Fock space of a N=2-string moving on a 4 dimensional torus can be described by a vertex algebra constructed from a rational lattice of signature (8,4). Here 6 coordinates with signature (4,2) come from the matter part and 6 coordinates with signature (4,2) come from the ghost part. The physical states are represented by the cohomology of the BRST-operator. The vertex algebra induces a product on the vector space of physical states that defines the structure of a Lie algebra on this space. This Lie algebra shares many properties with generalized Kac-Moody algebra but we will show that it is not a generalized Kac-Moody algebra. (orig.)

The Lie algebra of the N=2-string

Energy Technology Data Exchange (ETDEWEB)

Kugel, K

2006-07-01

The theory of generalized Kac-Moody algebras is a generalization of the theory of finite dimensional simple Lie algebras. The physical states of some compactified strings give realizations of generalized Kac-Moody algebras. For example the physical states of a bosonic string moving on a 26 dimensional torus form a generalized Kac-Moody algebra and the physical states of a N=1 string moving on a 10 dimensional torus form a generalized Kac-Moody superalgebra. A natural question is whether the physical states of the compactified N=2-string also realize such an algebra. In this thesis we construct the Lie algebra of the compactified N=2-string, study its properties and show that it is not a generalized Kac-Moody algebra. The Fock space of a N=2-string moving on a 4 dimensional torus can be described by a vertex algebra constructed from a rational lattice of signature (8,4). Here 6 coordinates with signature (4,2) come from the matter part and 6 coordinates with signature (4,2) come from the ghost part. The physical states are represented by the cohomology of the BRST-operator. The vertex algebra induces a product on the vector space of physical states that defines the structure of a Lie algebra on this space. This Lie algebra shares many properties with generalized Kac-Moody algebra but we will show that it is not a generalized Kac-Moody algebra. (orig.)

1997 State-by-State Assessment of Low-Level Radioactive Wastes Received at Commercial Disposal Sites

International Nuclear Information System (INIS)

Fuchs, R. L.

1998-01-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the United States. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1997 and a comparison of waste volumes and radioactivity by state for 1993 through 1997; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1997

Effects of low doses at the operation of nuclear power plants

International Nuclear Information System (INIS)

Mueck, K.; Wawra, E.

1978-07-01

In connexion with the debate on nuclear energy again and again attempts are found to threaten the public with incorrect or dramatically exaggerated statements about the effect of low-level-radiation by nuclear technology. Thereby a wrong impression in parts of the population about the dangers of low-level-radiaton doses arose. This paper shall help to clarify some of the misunderstandings and describe the present state of knowledge in this field in a way also understandable by the interested layman. (author)

The nuclear state

International Nuclear Information System (INIS)

Jungk, R.

1979-01-01

A general picture is given of the technical and sociological problems which it is said arise in the 'nuclear state'. Separate chapters are entitled: radiation fodder; the gamblers; the atomic man; the intimidated; the proliferators; atomic terrorists; the supervised. The Foreword, entitled 'the hard path' (i.e. with nuclear power) is contrasted with a final chapter entitled 'Prospect: the soft path' (i.e. without nuclear power). (U.K.)

Prospects for sub-micron solid state nuclear magnetic resonance imaging with low-temperature dynamic nuclear polarization.

Science.gov (United States)

Thurber, Kent R; Tycko, Robert

2010-06-14

We evaluate the feasibility of (1)H nuclear magnetic resonance (NMR) imaging with sub-micron voxel dimensions using a combination of low temperatures and dynamic nuclear polarization (DNP). Experiments are performed on nitroxide-doped glycerol-water at 9.4 T and temperatures below 40 K, using a 30 mW tunable microwave source for DNP. With DNP at 7 K, a 0.5 microL sample yields a (1)H NMR signal-to-noise ratio of 770 in two scans with pulsed spin-lock detection and after 80 db signal attenuation. With reasonable extrapolations, we infer that (1)H NMR signals from 1 microm(3) voxel volumes should be readily detectable, and voxels as small as 0.03 microm(3) may eventually be detectable. Through homonuclear decoupling with a frequency-switched Lee-Goldburg spin echo technique, we obtain 830 Hz (1)H NMR linewidths at low temperatures, implying that pulsed field gradients equal to 0.4 G/d or less would be required during spatial encoding dimensions of an imaging sequence, where d is the resolution in each dimension.

1996 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

Energy Technology Data Exchange (ETDEWEB)

Fuchs, R.L.

1997-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the US. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1996 and a comparison of waste volumes and radioactivity by state for 1992 through 1996; also included is a list of all commercial nuclear power reactors in the US as of December 31, 1996. This report distinguishes between low-level radioactive waste shipped directly for disposal by generators and waste that was handled by an intermediary, a reporting change introduced in the 1988 state-by-state report.

Introducing nuclear power into currently non-nuclear states

International Nuclear Information System (INIS)

Gert, Claassen

2007-01-01

As the nuclear renaissance gains momentum, many countries that currently have no nuclear power plants will begin to consider introducing them. It is anticipated that smaller reactors such as the Pebble Bed Modular Reactor (PBMR) will not only be sold to current nuclear states to also to states where there is currently no nuclear experience. A range of issues would have to be considered for nuclear plants to be sold to non-nuclear states, such as the appropriate regulatory environment, standardization and codes, non-proliferation, security of supply, obtaining experienced merchant operators, appropriate financial structures and education and training. The paper considers nine major issues that need to be addressed by governments and vendors alike: 1) political enabling framework, 2) regulatory framework, 3) responsible owner, 4) responsible operator, 5) finance, 6) contact management, 7) fuel supply and waste management framework, 8) training and education, and 9) industrial infrastructure. International cooperation by organisations such as the IAEA, financial institutions and international suppliers will be required to ensure that developing countries as well as developed ones share the benefits of the nuclear renaissance. The opportunities that the nuclear industry affords to develop local skills, create job opportunities and to develop local manufacturing industries are among the important reasons that the South African Government has decided to support and fund the development of the Pebble Bed Modular Reactor project. (author)

1992 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

International Nuclear Information System (INIS)

Fuchs, R.L.; McDonald, S.D.

1993-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the United States. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1992 and a comparison of waste volumes and radioactivity by state for 1988 through 1992; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1992. This report distinguishes between low-level radioactive waste shipped directly for disposal by generators and waste that was handled by an intermediary, a reporting change introduced in the 1988 state-by-state report

1994 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the United States. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1994 and a comparison of waste volumes and radioactivity by state for 1990 through 1994; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1994. This report distinguishes between low-level radioactive waste shipped directly for disposal by generators and waste that was handled by an intermediary, a reporting change introduced in the 1988 state-by-state report.

Low Dimensional Vessiot-Guldberg-Lie Algebras of Second-Order Ordinary Differential Equations

Directory of Open Access Journals (Sweden)

Rutwig Campoamor-Stursberg

2016-03-01

Full Text Available A direct approach to non-linear second-order ordinary differential equations admitting a superposition principle is developed by means of Vessiot-Guldberg-Lie algebras of a dimension not exceeding three. This procedure allows us to describe generic types of second-order ordinary differential equations subjected to some constraints and admitting a given Lie algebra as Vessiot-Guldberg-Lie algebra. In particular, well-known types, such as the Milne-Pinney or Kummer-Schwarz equations, are recovered as special cases of this classification. The analogous problem for systems of second-order differential equations in the real plane is considered for a special case that enlarges the generalized Ermakov systems.

Role of Electronic Structure In Ion Band State Theory of Low Energy Nuclear Reactions

Science.gov (United States)

Chubb, Scott

2004-03-01

The Nuts and Bolts of our Ion Band State (IBS) theory of low energy nuclear reactions (LENR's) in palladium-deuteride (PdD) and palladium-hydride (PdH) are the electrons that hold together or tear apart the bonds (or lack of bonds) between deuterons (d's) or protons (p's) and the host material. In PdDx and PdH_x, this bonding is strongly correlated with loading: in ambient loading conditions (x< 0. 6), the bonding in hibits IBS occupation. As x arrow 1, slight increases and decreases in loading can lead to vibrations (which have conventionally been thought to occur from phonons) that can induce potential losses or increases of p/d. Naive assumptions about phonons fail to include these losses and increases. These effects can occur because neither H or D has core electrons and because in either PdD or PdH, the electrons near the Fermi Energy have negligible overlap with the nucleus of either D or H. I use these ideas to develop a formal justification, based on a generalization of conventional band theory (Scott Chubb, "Semi-Classical Conduction of Charged and Neutral Particles in Finite Lattices," 2004 March Meeting."), for the idea that occupation of IBS's can occur and that this can lead to nuclear reactions.

Multi-project, multi-national, geographically dispersed: Challenges for the Nuclear Renaissance in the United States

International Nuclear Information System (INIS)

Mathews, T.A.

2007-01-01

The nuclear renaissance in the United States is moving at a rapid pace due to the incentives in the Energy Policy Act of 2005, recognition of the environmental benefits of nuclear energy, and the need for stable, reliable, and diverse sources of energy. The U.S. is looking externally to capitalize on French, German, Japanese, and other worldwide experience. A number of challenges to the resurgence of nuclear power are common worldwide, including project management, workforce and supplier availability and large-project construction management experience. For example, AREVA's new plant project teams are comprised of resources drawn from various U.S. centers of technical expertise and backed up by AREVA's worldwide capabilities. However, the challenge lies in having the information infrastructure in place to integrate that expertise and share information across working groups. In another example, the U.S. regulatory process has changed significantly for the better, but the new streamlined combined license process has not been tested. Reactor vendors and utilities have injected new thinking into the process by pursuing Design Certification, Early Site Permit, and Combined License approval in parallel rather than in series. This paper will discuss these and other challenges to licensing and building new nuclear plants, and the approaches being used by AREVA to lead the Nuclear Renaissance in the United States. (author)

Microscopic boson approach to nuclear collective motion

International Nuclear Information System (INIS)

Kuchta, R.

1989-01-01

A quantum mechanical approach to the maximally decoupled nuclear collective motion is proposed. The essential idea is to transcribe the original shell-model Hamiltonian in terms of boson operators, then to isolate the collective one-boson eigenstates of the mapped Hamiltonian and to perform a canonical transformation which eliminates (up to the two-body terms) the coupling between the collective and noncollective bosons. Unphysical states arising due to the violtion of the Pauli principle in the boson space are identified and removed within a suitable approximation. The method is applied to study the low-lying collective states of nuclei which are successfully described by the exactly solvable multilevel pairing Hamiltonian (Sn, Ni, Pb). 75 refs.; 8 figs

Iran: the next nuclear threshold state?

OpenAIRE

Maurer, Christopher L.

2014-01-01

Approved for public release; distribution is unlimited A nuclear threshold state is one that could quickly operationalize its peaceful nuclear program into one capable of producing a nuclear weapon. This thesis compares two known threshold states, Japan and Brazil, with Iran to determine if the Islamic Republic could also be labeled a threshold state. Furthermore, it highlights the implications such a status could have on U.S. nonproliferation policy. Although Iran's nuclear program is mir...

Study of the Neutron Deficient Pb and Bi Isotopes by Simultaneous Atomic- and Nuclear-Spectroscopy

CERN Multimedia

Kessler, T

2002-01-01

We propose to study systematically nuclear properties of the neutron deficient lead $^{183-189}$Pb, $^{191g}$Pb, $^{193g}$Pb and bismuth isotopes $^{188-200}$Bi by atomic spectroscopy with the ISOLDE resonance ionisation laser ion source (RILIS) combined with simultaneous nuclear spectroscopy at the detection set-up. The main focus is the determination of the mean square charge radii of $^{183-190}$Pb and $^{188-193}$Bi from which the influence of low-lying intruder states should become obvious. Also the nuclear spin and magnetic moments of ground-states and long-lived isomers will be determined unambiguously through evaluation of the hyperfine structure, and new isomers could be discovered. The decay properties of these nuclei can be measured by $\\alpha$-$\\gamma$ and $\\beta$-$\\gamma$ spectroscopy. With this data at hand, possible shape transitions around mid-shell at N$\\sim$104 will be studied. This data is crucial for the direct test of nuclear theory in the context of intruder state influence (e.g. energy ...

The Prevalence and Role of Low Lying Peroneus Brevis Muscle Belly in Patients with Peroneal Tendon Pathologies: A Potential Source for Tendon Subluxation

OpenAIRE

Mirmiran, Roya; Squire, Chad; Wassell, Daniel

2015-01-01

A low lying peroneus brevis muscle belly is a rare anomaly. There are few published studies that support presence of this anomaly as an etiology for peroneal tendon tear. However, the association between a low lying peroneus muscle belly (LLMB) and tendon subluxation is not well explored. In this retrospective study, the magnetic resonance imaging (MRI) and intraoperative findings of 50 consecutive patients undergoing a primary peroneal tendon surgery, in a five year period, were assessed. Th...

1990 State-by-State assessment of low-level radioactive wastes received at commercial disposal sites

International Nuclear Information System (INIS)

Fuchs, R.L.; Culbertson-Arendts, K.

1991-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This annual report provides both national and state-specific disposal data on low-level radioactive wastes. Data in this report are categorized according to disposal site, generator category, waste class, volume, and activity. Included in this report are tables showing a distribution of wastes by state for 1990 and a comparison of waste volumes by state for 1986 through 1990; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1990. In this year's report, a distinction has been made between low-level radioactive waste shipped directly by generators for disposal and that which was handled by an intermediary. 5 refs., 4 tabs

1990 State-by-State assessment of low-level radioactive wastes received at commercial disposal sites

Energy Technology Data Exchange (ETDEWEB)

Fuchs, R.L.; Culbertson-Arendts, K.

1991-09-01

Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This annual report provides both national and state-specific disposal data on low-level radioactive wastes. Data in this report are categorized according to disposal site, generator category, waste class, volume, and activity. Included in this report are tables showing a distribution of wastes by state for 1990 and a comparison of waste volumes by state for 1986 through 1990; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1990. In this year's report, a distinction has been made between low-level radioactive waste shipped directly by generators for disposal and that which was handled by an intermediary. 5 refs., 4 tabs.

Oscillator strengths and lifetimes for low-lying terms in the Al isoelectronic sequence

International Nuclear Information System (INIS)

Hjort-Jensen, M.; Aashamar, K.

1988-11-01

Using the Multiconfiguration Optimized Potential Model, calculations of oscillator strengths in the length, and velocity formulation for a large number of transitions in the Aluminium isoelectronic sequence from Si II through K VII, have been performed. The results have been used to determine the lifetimes of 14 low-lying excited terms along the sequence. Comparison is made with experiment and with other theory where results are available. The agreement between the obtained values and other theoretical results is generally good, although deviations do occur near level crossings. Some significant discrepancies between theory and experiment persist concerning lifetimes for S IV

Evolution of the low-lying dipole strength in deformed nuclei with extreme neutron excess with the Relativistic QRPA

International Nuclear Information System (INIS)

Pena Arteaga, D.; Khan, E.; Ring, P.

2009-01-01

Covariant density functional theory, in the framework of self-consistent Relativistic Hartree Bogoliubov (HFB) and Relativistic Quasiparticle Random Phase approximation (RQRPA), is for the first time applied to axially deformed nuclei [1]. The fully self-consistent RHB+RQRPA equations are posed for the case of axial symmetry and different energy functionals, and solved with the help of a new parallel code. As a sample application, the El strength is systematically analyzed in very neutron-rich Sn nuclei, beyond 1 32S n until 1 66S n [2]. The great neutron excess favors the appearance of a deformed ground state for 1 42-162S n. The evolution of the low-lying strength in deformed nuclei is discussed, and in particular its dependence on the interplay of two major and competing factors, isospin asymmetry and deformation.(author)

Deformed nuclear state as a quasiparticle-pair

International Nuclear Information System (INIS)

Dobaczewski, J.; Skalski, J.

1988-01-01

The deformed nuclear states, obtained in terms of the Hartree-Fock plus BCS method with the Skyrme SIII interaction, are approximated by condensates of the low-angular-momentum quasiparticle and particle pairs. The optimal pairs are determined by the variation after truncation method. The influence of the truncation on the deformation energy and the importance of the core-polarization effects are investigated

Grupos de Lie

OpenAIRE

Rubio Martí, Vicente

2016-01-01

En el presente proyecto definimos lo que es un grupo de Lie, así como su respectiva álgebra de Lie canónica como aproximación lineal a dicho grupo de Lie. El proceso de linealización, que es hallar el algebra de Lie de un grupo de Lie dado, tiene su

The state of nuclear forensics

International Nuclear Information System (INIS)

Kristo, Michael J.; Tumey, Scott J.

2013-01-01

Nuclear terrorism has been identified as one of the most serious security threats facing the world today. Many countries, including the United States, have incorporated nuclear forensic analysis as a component of their strategy to prevent nuclear terrorism. Nuclear forensics involves the laboratory analysis of seized illicit nuclear materials or debris from a nuclear detonation to identify the origins of the material or weapon. Over the years, a number of forensic signatures have been developed to improve the confidence with which forensic analysts can draw conclusions. These signatures are validated and new signatures are discovered through research and development programs and in round-robin exercises among nuclear forensic laboratories. The recent Nuclear Smuggling International Technical Working Group Third Round Robin Exercise and an on-going program focused on attribution of uranium ore concentrate provide prime examples of the current state of nuclear forensics. These case studies will be examined and the opportunities for accelerator mass spectrometry to play a role in nuclear forensics will be discussed.

The state of nuclear forensics

Energy Technology Data Exchange (ETDEWEB)

Kristo, Michael J. [Chemical Sciences Division, Lawrence Livermore National Laboratory, P.O. Box 808, L-186, Livermore, CA 94551 (United States); Tumey, Scott J., E-mail: tumey2@llnl.gov [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, P.O. Box 808, L-397, Livermore, CA 94551 (United States)

2013-01-15

Nuclear terrorism has been identified as one of the most serious security threats facing the world today. Many countries, including the United States, have incorporated nuclear forensic analysis as a component of their strategy to prevent nuclear terrorism. Nuclear forensics involves the laboratory analysis of seized illicit nuclear materials or debris from a nuclear detonation to identify the origins of the material or weapon. Over the years, a number of forensic signatures have been developed to improve the confidence with which forensic analysts can draw conclusions. These signatures are validated and new signatures are discovered through research and development programs and in round-robin exercises among nuclear forensic laboratories. The recent Nuclear Smuggling International Technical Working Group Third Round Robin Exercise and an on-going program focused on attribution of uranium ore concentrate provide prime examples of the current state of nuclear forensics. These case studies will be examined and the opportunities for accelerator mass spectrometry to play a role in nuclear forensics will be discussed.

Generator Coordinate Method Analysis of Xe and Ba Isotopes

Science.gov (United States)

Higashiyama, Koji; Yoshinaga, Naotaka; Teruya, Eri

Nuclear structure of Xe and Ba isotopes is studied in terms of the quantum-number projected generator coordinate method (GCM). The GCM reproduces well the energy levels of high-spin states as well as low-lying states. The structure of the low-lying states is analyzed through the GCM wave functions.

Right Inferior Frontal Gyrus Activation as a Neural Marker of Successful Lying

Directory of Open Access Journals (Sweden)

Oshin eVartanian

2013-10-01

Full Text Available There is evidence to suggest that successful lying necessitates cognitive effort. We tested this hypothesis by instructing participants to lie or tell the truth under conditions of high and low working memory (WM load. The task required participants to register a response on 80 trials of identical structure within a 2 (WM Load: high, low × 2 (Instruction: truth or lie repeated-measures design. Participants were less accurate and responded more slowly when WM load was high, and also when they lied. High WM load activated the fronto-parietal WM network including dorsolateral prefrontal cortex (PFC, middle frontal gyrus, precuneus, and intraparietal cortex. Lying activated areas previously shown to underlie deception, including middle and superior frontal gyrus and precuneus. Critically, successful lying in the high vs. low WM load condition was associated with longer response latency, and it activated the right inferior frontal gyrus—a key brain region regulating inhibition. The same pattern of activation in the inferior frontal gyrus was absent when participants told the truth. These findings demonstrate that lying under high cognitive load places a burden on inhibition, and that the right inferior frontal gyrus may provide a neural marker for successful lying.

Right inferior frontal gyrus activation as a neural marker of successful lying.

Science.gov (United States)

Vartanian, Oshin; Kwantes, Peter J; Mandel, David R; Bouak, Fethi; Nakashima, Ann; Smith, Ingrid; Lam, Quan

2013-01-01

There is evidence to suggest that successful lying necessitates cognitive effort. We tested this hypothesis by instructing participants to lie or tell the truth under conditions of high and low working memory (WM) load. The task required participants to register a response on 80 trials of identical structure within a 2 (WM Load: high, low) × 2 (Instruction: truth or lie) repeated-measures design. Participants were less accurate and responded more slowly when WM load was high, and also when they lied. High WM load activated the fronto-parietal WM network including dorsolateral prefrontal cortex (PFC), middle frontal gyrus, precuneus, and intraparietal cortex. Lying activated areas previously shown to underlie deception, including middle and superior frontal gyrus and precuneus. Critically, successful lying in the high vs. low WM load condition was associated with longer response latency, and it activated the right inferior frontal gyrus-a key brain region regulating inhibition. The same pattern of activation in the inferior frontal gyrus was absent when participants told the truth. These findings demonstrate that lying under high cognitive load places a burden on inhibition, and that the right inferior frontal gyrus may provide a neural marker for successful lying.

M1 transitions between low-lying states in the sdg-IBM-2

Science.gov (United States)

Casperson, Robert; Werner, Volker

2006-10-01

The interplay between collective and single-particle degrees of freedom for nuclei in the A=90 region have recently been under investigation. In Molybdenum and Ruthenium nuclei, collective symmetric and mixed-symmetric structures have been identified, while in Zirconium, underlying shell-structure plays an enhanced role. Collective symmetric structures appear when protons and neutrons are in phase, whereas mixed-symmetric structures occur when they are not. The one-phonon 2^+ mixed-symmetric state was identified from strong M1 transitions to the 2^+1 state. Similar transitions were observed between higher-spin states, and are predicted by the shell model. These phenomena will be investigated within the sdg Interacting Boson Model 2 in order to obtain a better understanding about the structure of the states involved, and results from first model calculations will be presented. Work supported by US DOE under grant number DE-FG02-91ER-40609.

Intruder states at the N=20 shell closure

International Nuclear Information System (INIS)

Heyde, K.

1991-01-01

It is indicated that mp-mh (multiple) excitations across closed shells can occur at low energy throughout the nuclear mass region. Besides the 4p-4h, 8p-8h configurations, that are deformed, coexisting low-lying excitations are mainly observed for light N=Z nuclei. A new class of 2p-2h intruder O + state is shown to exist in nuclei where a neutron excess is present. In the latter cases, the proton-neutron interaction energy between the excited 2p-2h configuration and the open shell accounts for a very specific mass dependence in the intruder excitation energy. The experimental evidence that corroborates the idea of intruder states will be given. (G.P.) 28 refs.; 13 figs

Hot metastable state of abnormal matter in relativistic nuclear field theory

International Nuclear Information System (INIS)

Glendenning, N.K.

1987-01-01

Because of their non-linearity, the field equations of relativistic nuclear field theory admit of additional solutions besides the normal state of matter. One of these is a finite-temperature abnormal phase. Over a narrow range in temperature, matter can exist in the abnormal phase at zero pressure. This is a hot metastable state, for which there is a barrier against decay, because the field configuration is different than in the normal state, the baryon masses are far removed from their vacuum masses, there is an abundance of pairs also far removed from their vacuum masses, and a correspondingly high entropy. The abundance of baryon-antibaryon pairs is the glue that holds this matter together. The signals associated with this novel state are quite unusual. A fragment of such matter will cool by emitting a spectrum of black-body radiation, consisting principally of photons, lepton pairs and pions, rather than by baryon emission, because the latter are far removed from their vacuum masses. If produced at the upper end of its temperature range, a large fraction of the original energy, more than half in the examples studied here, is radiated in this way. The baryons and light elements produced in the eventual decay, after the abnormal matter has cooled to a domain where its pressure becomes positive, will account for only a fraction of the original energy. The energy domain of this state depends sensitively on the coupling constants, and within a reasonable range as determined by nuclear matter properties, can lie in the range of GeV to tens of GeV per nucleon. (orig.)

Systematics of ground state multiplets of atomic nuclei in the delta-interaction approach

Energy Technology Data Exchange (ETDEWEB)

Imasheva, L. T.; Ishkhanov, B. S.; Stepanov, M. E., E-mail: stepanov@depni.sinp.msu.ru [Moscow State University, Faculty of Physics (Russian Federation); Tretyakova, T. Yu. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

2015-12-15

Pairing forces between nucleons in an atomic nucleus strongly influence its structure. One of the manifestations of pair interaction is the ground state multiplet (GSM) formation in the spectrum of low-lying excited states of even–even nuclei. The value of GSM splitting is determined by the value of pair interaction of nucleons; for each isotope, it can be estimated on the basis of experimental nuclear masses. The quality of this estimate is characterized by the degree of reproduction of GSM levels in the nucleus. The GSM systematics in even–even nuclei with a pair of identical nucleons in addition to the filled nuclear core is considered on the basis of delta interaction.

Low-lying isomeric states in Ga-80 from the beta(-) decay of Zn-80

Czech Academy of Sciences Publication Activity Database

Lica, R.; Marginean, N.; Ghita, D. G.; Mach, H.; Simpson, G. S.; Aprahamian, A.; Bernards, C.; Briz, J. A.; Bucher, B.; Chiara, C. J.; Dlouhý, Zdeněk; Gheorghe, I.; Hoff, P.; Jolie, J.; Koster, U.; Kurcewicz, W.; Marginean, R.; Olaizola, B.; Paziy, V.; Regis, J. M.; Rudigier, M.; Sava, T.; Stanoiu, M.; Stroe, L.; Walters, W. B.

2014-01-01

Roč. 90, č. 1 (2014), 014320 ISSN 0556-2813 Institutional support: RVO:61389005 Keywords : picosecond lifetime measurements * neutron-rich nuclei * Zn Subject RIV: BG - Nuclear, Atomic and Molecular Physics , Colliders Impact factor: 3.733, year: 2014

Low-energy nuclear physics with high-segmentation silicon arrays

International Nuclear Information System (INIS)

Betts, R.R.; Univ. of Illinois, Chicago, IL

1994-01-01

A brief history is given of silicon detectors leading up to the development of ion-implanted strip detectors. Two examples of their use in low energy nuclear physics are discussed; the search for exotic alpha-chain states in 24 Mg and studies of anomalous positron-electron pairs produced in collisions of very heavy ions

Nuclear electric power and the proliferation of nuclear weapon states

International Nuclear Information System (INIS)

Walske, C.

1977-01-01

Control and elimination of the strategic nuclear weapons held by the nuclear weapon states remains the central problem in the arms control and disarmament field. Whether the proliferation of nations with nuclear weapons can be stopped is dubious. A sovereign nation will launch a nuclear weapons program if it has the motivation and resource. Motivation depends on military and political considerations. The necessary resources are economic and technological. Conditions in some sovereign states explain this issue. A survey of commercial nuclear power programs outside the USA lists 45 countries using or planning to use nuclear reactors for power generation. There are currently 112 reactors now operating outside the United States, 117 more under construction, 60 on order, and 180 planned. The U. S. as of December 1976 has 64 operating reactors, 72 under construction, 84 on order, and 8 planned. Nuclear trade and export policies are discussed. In this article, Mr. Walske says that American industry is convinced that the need for nuclear energy abroad is more urgent than in the United States; that in the long run, the breeder reactor must be developed to enable the supply of nuclear fuel to last for centuries; and that the experience of American industry abroad has convinced it that emphasis on restrictive, denial type policies will almost certainly fail--a collapse of what has been gained through the test ban treaty and the nonproliferation treaty

Nuclear energy for a low-carbon France

International Nuclear Information System (INIS)

Faudon, Valerie; Jouette, Isabelle; Le Ngoc, Boris

2015-01-01

This publication states the opinion of the SFEN (the French Society of Nuclear Energy) about the implementation of the French Multi-year Energy Programming (PPE). The authors first outline that the PPE must firstly aim at reducing greenhouse gas emissions. As a second point, they outline that the PPE must remain flexible in order to be able to face uncertainties related to supply (growth of renewable energies) and demand (economic recovery, pace of energetic installation renewal), and to guard against energy-related events (oil shocks, Russian-Ukrainian crisis, and so on) through a right planning of the energy mix diversification with taking the improvement of economic and technological performance of renewable energies into account. As a third point, they outline that nuclear energy is the base of a low-carbon France. They finally discuss perspectives to strengthen this base by a sustained investment in the nuclear fleet, in the fuel recycling sector, and in research for the development of a new generation of reactors

Nucleon-pair approximation to the nuclear shell model

Energy Technology Data Exchange (ETDEWEB)

Zhao, Y.M., E-mail: ymzhao@sjtu.edu.cn [Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Arima, A. [Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Musashi Gakuen, 1-26-1 Toyotamakami Nerima-ku, Tokyo 176-8533 (Japan)

2014-12-01

Atomic nuclei are complex systems of nucleons–protons and neutrons. Nucleons interact with each other via an attractive and short-range force. This feature of the interaction leads to a pattern of dominantly monopole and quadrupole correlations between like particles (i.e., proton–proton and neutron–neutron correlations) in low-lying states of atomic nuclei. As a consequence, among dozens or even hundreds of possible types of nucleon pairs, very few nucleon pairs such as proton and neutron pairs with spin zero, two (in some cases spin four), and occasionally isoscalar spin-aligned proton–neutron pairs, play important roles in low-energy nuclear structure. The nucleon-pair approximation therefore provides us with an efficient truncation scheme of the full shell model configurations which are otherwise too large to handle for medium and heavy nuclei in foreseeable future. Furthermore, the nucleon-pair approximation leads to simple pictures in physics, as the dimension of nucleon-pair subspace is always small. The present paper aims at a sound review of its history, formulation, validity, applications, as well as its link to previous approaches, with the focus on the new developments in the last two decades. The applicability of the nucleon-pair approximation and numerical calculations of low-lying states for realistic atomic nuclei are demonstrated with examples. Applications of pair approximations to other problems are also discussed.

Clustering and Symmetry Energy in a Low Density Nuclear Gas

International Nuclear Information System (INIS)

Kowalski, S.; Natowitz, J.B.; Shlomo, S.; Wada, R.; Hagel, K.; Wang, J.; Materna, T.; Chen, Z.; Ma, Y.G.; Qin, L.; Botvina, A.S.; Fabris, D.; Lunardon, M.; Moretto, S.; Nebbia, G.; Pesente, S.; Rizzi, V.; Viesti, G.; Cinausero, M.; Prete, G.; Keutgen, T.; El Masri, Y.; Majka, Z.; Ono, A.

2007-01-01

Temperature and density dependent symmetry energy coefficients have been derived from isoscaling analyses of the yields of nuclei with A= 64 Zn projectiles with 92 Mo and 197 Au target nuclei. The symmetry energies at low density are larger than those obtained in mean field calculations, reflecting the clustering of low density nuclear matter. They are in quite good agreement with results of a recently proposed Virial Equation of State calculation

Statement at NRC International Regulators Conference on Nuclear Security, 4 December 2012, Washington, United States

International Nuclear Information System (INIS)

Amano, Y.

2012-01-01

I would like to begin by thanking NRC Chairman Allison Macfarlane for hosting this first regulatory Conference on nuclear security involving regulators, law enforcement agencies and the IAEA. The United States has been a very important partner in the IAEA's nuclear security activities right from the start. It is by far the largest donor to our Nuclear Security Fund. It has actively supported our programmes and has been generous in providing funding, equipment and training to other Member States. When President Obama hosted the first Nuclear Security Summit in April 2010, he said it was important that that event should be part of a ''serious and sustained effort'' to improve nuclear security throughout the world. Since then, a growing number of governments have given high-level attention to this vitally important issue. This is very encouraging. Today, I am especially pleased to see regulators coming together to focus on this subject. I am confident that your meeting will make a valuable contribution to strengthening global nuclear security. I would like to share with you some important recent milestones in the IAEA's nuclear security work. As you know, primary responsibility for ensuring nuclear security lies with national governments. However, governments have recognized that international cooperation is vital. Terrorists and other criminals do not respect international borders and no country can respond effectively on its own to the threat which they pose. In September, our Member States - there are now 158 - reaffirmed the central role of the IAEA in e nsuring coordination of international activities in the field of nuclear security, while avoiding duplication and overlap . Our central role reflects the Agency's extensive membership, our mandate, our unique expertise and our long experience of providing technical assistance and specialist, practical guidance to countries. To put it simply, our work focuses on helping to minimize the risk of nuclear and other

Predictors of children's prosocial lie-telling: Motivation, socialization variables, and moral understanding.

Science.gov (United States)

Popliger, Mina; Talwar, Victoria; Crossman, Angela

2011-11-01

Children tell prosocial lies for self- and other-oriented reasons. However, it is unclear how motivational and socialization factors affect their lying. Furthermore, it is unclear whether children's moral understanding and evaluations of prosocial lie scenarios (including perceptions of vignette characters' feelings) predict their actual prosocial behaviors. These were explored in two studies. In Study 1, 72 children (36 second graders and 36 fourth graders) participated in a disappointing gift paradigm in either a high-cost condition (lost a good gift for a disappointing one) or a low-cost condition (received a disappointing gift). More children lied in the low-cost condition (94%) than in the high-cost condition (72%), with no age difference. In Study 2, 117 children (42 preschoolers, 41 early elementary school age, and 34 late elementary school age) participated in either a high- or low-cost disappointing gift paradigm and responded to prosocial vignette scenarios. Parents reported on their parenting practices and family emotional expressivity. Again, more children lied in the low-cost condition (68%) than in the high-cost condition (40%); however, there was an age effect among children in the high-cost condition. Preschoolers were less likely than older children to lie when there was a high personal cost. In addition, compared with truth-tellers, prosocial liars had parents who were more authoritative but expressed less positive emotion within the family. Finally, there was an interaction between children's prosocial lie-telling behavior and their evaluations of the protagonist's and recipient's feelings. Findings contribute to understanding the trajectory of children's prosocial lie-telling, their reasons for telling such lies, and their knowledge about interpersonal communication. Copyright © 2011 Elsevier Inc. All rights reserved.

A comparison of the nuclear options for greenhouse gas mitigation in China and in the United States

Energy Technology Data Exchange (ETDEWEB)

Yang, Chi-Jen, E-mail: cj.y@duke.edu [Center on Global Change, Box 90658, Duke University, Durham, NC 27708 (United States)

2011-06-15

China is quickly building up its nuclear power capacity while the hailed nuclear renaissance in the United States has been largely stagnant. The political and industrial structures explain the divergent paths. This paper draws lessons from the French experiences in deploying nuclear power and uses the lessons in comparing Chinese and U.S. policies. An authoritative political system and state-owned utility industry allow China to emulate the French approaches such as government-backed financing and broad-scale deployment with standardized design. The democratic political system and fragmented utility industry, and the laissez-faire ideology in the United States, on the other hand, are unfavorable to a nuclear renaissance. The prospect of a nuclear revival in the United States remains highly uncertain. As China builds up its nuclear industry, it will be able to reduce carbon emissions without a carbon price through a national plan to deploy low-carbon nuclear electricity, while the United States cannot implement a climate policy without a carbon price. American politicians should stop using China's lack of carbon cap as an excuse for postponing the legislation of a carbon price. - Highlights: > The Chinese government and Chinese state-owned companies are indigenizing nuclear power technologies, establishing nuclear manufacturing capacity, and gradually scaling up nuclear power deployment. > China is likely on a path to the biggest nuclear buildup in human history. > The hailed nuclear renaissance in the United States has been largely stagnant. > The underlying causes of U.S. Nuclear stagnation is rooted in the democratic political system and fragmented utility industry, and the laissez-faire ideology, which are unlikely to change in the foreseeable future. > China can move toward a low-carbon electricity system without a carbon price. The United States needs a carbon price to implement a climate policy.

A comparison of the nuclear options for greenhouse gas mitigation in China and in the United States

International Nuclear Information System (INIS)

Yang, Chi-Jen

2011-01-01

China is quickly building up its nuclear power capacity while the hailed nuclear renaissance in the United States has been largely stagnant. The political and industrial structures explain the divergent paths. This paper draws lessons from the French experiences in deploying nuclear power and uses the lessons in comparing Chinese and U.S. policies. An authoritative political system and state-owned utility industry allow China to emulate the French approaches such as government-backed financing and broad-scale deployment with standardized design. The democratic political system and fragmented utility industry, and the laissez-faire ideology in the United States, on the other hand, are unfavorable to a nuclear renaissance. The prospect of a nuclear revival in the United States remains highly uncertain. As China builds up its nuclear industry, it will be able to reduce carbon emissions without a carbon price through a national plan to deploy low-carbon nuclear electricity, while the United States cannot implement a climate policy without a carbon price. American politicians should stop using China's lack of carbon cap as an excuse for postponing the legislation of a carbon price. - Highlights: → The Chinese government and Chinese state-owned companies are indigenizing nuclear power technologies, establishing nuclear manufacturing capacity, and gradually scaling up nuclear power deployment. → China is likely on a path to the biggest nuclear buildup in human history. → The hailed nuclear renaissance in the United States has been largely stagnant. → The underlying causes of U.S. Nuclear stagnation is rooted in the democratic political system and fragmented utility industry, and the laissez-faire ideology, which are unlikely to change in the foreseeable future. → China can move toward a low-carbon electricity system without a carbon price. The United States needs a carbon price to implement a climate policy.

Lie superalgebras

International Nuclear Information System (INIS)

Berezin, F.A.

1977-01-01

Generalization of the Laplace-Casimir operator theory on the Lie supergroups is considered. The main result is the formula for radial parts of the Laplace operators under some general assumptions about the Lie supergroup. In particular these assumptions are valid for the Lie suppergroups U(p,g) and C (m,n). The first one is the analogue of the unitary group, the second one is the analogue of the linear group of canonical transformations

"Lie to me"-Oxytocin impairs lie detection between sexes.

Science.gov (United States)

Pfundmair, Michaela; Erk, Wiebke; Reinelt, Annika

2017-10-01

The hormone oxytocin modulates various aspects of social behaviors and even seems to lead to a tendency for gullibility. The aim of the current study was to investigate the effect of oxytocin on lie detection. We hypothesized that people under oxytocin would be particularly susceptible to lies told by people of the opposite sex. After administration of oxytocin or a placebo, male and female participants were asked to judge the veracity of statements from same- vs. other-sex actors who either lied or told the truth. Results showed that oxytocin decreased the ability of both male and female participants to correctly classify other-sex statements as truths or lies compared to placebo. This effect was based on a lower ability to detect lies and not a stronger bias to regard truth statements as false. Revealing a new effect of oxytocin, the findings may support assumptions about the hormone working as a catalyst for social adaption. Copyright © 2017. Published by Elsevier Ltd.

Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals

International Nuclear Information System (INIS)

2013-01-01

The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

Embedded random matrix ensembles from nuclear structure and their recent applications

Science.gov (United States)

Kota, V. K. B.; Chavda, N. D.

Embedded random matrix ensembles generated by random interactions (of low body rank and usually two-body) in the presence of a one-body mean field, introduced in nuclear structure physics, are now established to be indispensable in describing statistical properties of a large number of isolated finite quantum many-particle systems. Lie algebra symmetries of the interactions, as identified from nuclear shell model and the interacting boson model, led to the introduction of a variety of embedded ensembles (EEs). These ensembles with a mean field and chaos generating two-body interaction generate in three different stages, delocalization of wave functions in the Fock space of the mean-field basis states. The last stage corresponds to what one may call thermalization and complex nuclei, as seen from many shell model calculations, lie in this region. Besides briefly describing them, their recent applications to nuclear structure are presented and they are (i) nuclear level densities with interactions; (ii) orbit occupancies; (iii) neutrinoless double beta decay nuclear transition matrix elements as transition strengths. In addition, their applications are also presented briefly that go beyond nuclear structure and they are (i) fidelity, decoherence, entanglement and thermalization in isolated finite quantum systems with interactions; (ii) quantum transport in disordered networks connected by many-body interactions with centrosymmetry; (iii) semicircle to Gaussian transition in eigenvalue densities with k-body random interactions and its relation to the Sachdev-Ye-Kitaev (SYK) model for majorana fermions.

Three-body hadronic structure of low-lying 1/2+ Σ and Λ resonances

International Nuclear Information System (INIS)

Martinez Torres, A.; Khemchandani, K.P.; Oset, E.

2008-01-01

We discuss the dynamical generation of some low-lying 1/2 + Σ's and Λ's in two-meson one-baryon systems. These systems have been constructed by adding a pion in the S-wave to the anti KN pair and its coupled channels, where the 1/2 - Λ(1405)-resonance gets dynamically generated. We solve Faddeev equations in the coupled-channel approach to calculate the T-matrix for these systems as a function of the total energy and the invariant mass of one of the meson-baryon pairs. This squared T-matrix shows peaks at the energies very close to the masses of the strangeness -1,1/2 + resonances listed in the particle data book. (orig.)

Lie construction affects information storage under high memory load condition.

Directory of Open Access Journals (Sweden)

Yuqiu Liu

Full Text Available Previous studies indicate that lying consumes cognitive resources, especially working memory (WM resources. Considering the dual functions that WM might play in lying: holding the truth-related information and turning the truth into lies, the present study examined the relationship between the information storage and processing in the lie construction. To achieve that goal, a deception task based on the old/new recognition paradigm was designed, which could manipulate two levels of WM load (low-load task using 4 items and high-load task using 6 items during the deception process. The analyses based on the amplitude of the contralateral delay activity (CDA, a proved index of the number of representations being held in WM, showed that the CDA amplitude was lower in the deception process than that in the truth telling process under the high-load condition. In contrast, under the low-load condition, no CDA difference was found between the deception and truth telling processes. Therefore, we deduced that the lie construction and information storage compete for WM resources; when the available WM resources cannot meet this cognitive demand, the WM resources occupied by the information storage would be consumed by the lie construction.

Lie construction affects information storage under high memory load condition.

Science.gov (United States)

Liu, Yuqiu; Wang, Chunjie; Jiang, Haibo; He, Hongjian; Chen, Feiyan

2017-01-01

Previous studies indicate that lying consumes cognitive resources, especially working memory (WM) resources. Considering the dual functions that WM might play in lying: holding the truth-related information and turning the truth into lies, the present study examined the relationship between the information storage and processing in the lie construction. To achieve that goal, a deception task based on the old/new recognition paradigm was designed, which could manipulate two levels of WM load (low-load task using 4 items and high-load task using 6 items) during the deception process. The analyses based on the amplitude of the contralateral delay activity (CDA), a proved index of the number of representations being held in WM, showed that the CDA amplitude was lower in the deception process than that in the truth telling process under the high-load condition. In contrast, under the low-load condition, no CDA difference was found between the deception and truth telling processes. Therefore, we deduced that the lie construction and information storage compete for WM resources; when the available WM resources cannot meet this cognitive demand, the WM resources occupied by the information storage would be consumed by the lie construction.

The 1988 state-by-state assessment of Low-Level Radioactive Wastes received at commercial disposal sites

International Nuclear Information System (INIS)

Fuchs, R.L.; Culbertson-Arendts, K.

1989-12-01

This report provides both national and state-specific disposal data on low-level radioactive wastes. Data in this report are divided into generator categories, waste classes, volumes, and activities. Included in this report are tables showing a distribution of wastes by state for 1988 and a comparison of waste volumes by state for 1984 through 1988; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1988. In this year's report, a distinction has been made between low-level radioactive waste shipped directly for disposal by generators and that which was handled by an intermediary. 8 refs., 3 tabs

Key technologies for the current and future challenges of the nuclear industry

International Nuclear Information System (INIS)

Martinez-Sancho, Lou; Roulleaux Dugage, Martin

2017-01-01

The current challenges of the nuclear industry are the result of too many uncertainties: low GDP growth of OECD countries, booming state debts, deregulated electricity markets, growing safety regulation and diminishing public support. As a result, nuclear technology companies tend to entrench in their current installed base, while attempting to develop global partnerships to market their products to new nuclear countries, along with viable financing schemes. But new opportunities are lying ahead. In a future context of effective and global climate policies, nuclear energy will have to play a key role in a new energy ecosystem aside the two other clean air energy production technologies: renewable energies and electricity storage. And still, the perspective of long-term sustainability of nuclear energy is still high. This paper explores the opportunity for key innovative technologies to shift the way we think about nuclear in the future energy system while addressing these major challenges. (author)

Energy spectra of vibron and cluster models in molecular and nuclear systems

Science.gov (United States)

Jalili Majarshin, A.; Sabri, H.; Jafarizadeh, M. A.

2018-03-01

The relation of the algebraic cluster model, i.e., of the vibron model and its extension, to the collective structure, is discussed. In the first section of the paper, we study the energy spectra of vibron model, for diatomic molecule then we derive the rotation-vibration spectrum of 2α, 3α and 4α configuration in the low-lying spectrum of 8Be, 12C and 16O nuclei. All vibrational and rotational states with ground and excited A, E and F states appear to have been observed, moreover the transitional descriptions of the vibron model and α-cluster model were considered by using an infinite-dimensional algebraic method based on the affine \\widehat{SU(1,1)} Lie algebra. The calculated energy spectra are compared with experimental data. Applications to the rotation-vibration spectrum for the diatomic molecule and many-body nuclear clusters indicate that there are solvable models and they can be approximated very well using the transitional theory.

2. International workshop Solid state nuclear track detectors and their applications

International Nuclear Information System (INIS)

Perelygin, V.P.

1992-01-01

The 2. Workshop on Solid state nuclear track detectors (SSNTD) held in Dubna, 24-26 Mar 1992. Possibilities of SSNTD applications in the fields of high and low energy physics, dosimetry and radioecology were discussed

Nuclear development in the United States

International Nuclear Information System (INIS)

Brewer, S.

1983-01-01

The history of the nuclear development in the United States has been one of international cooperation relations so far. The United States is to offer the technical information on atomic energy utilization to foreign countries in exchange for the guarantee that they never attempt to have or develop nuclear weapons. Actually, the United States has supplied the technologies on nuclear fuel cycle and other related fields to enable other countries to achieve economical and social progress. The Department of Energy clarified the public promise of the United States regarding the idea of international energy community. The ratio of nuclear power generation to total electric power supply in the United States exceeded 12%, and will exceed 20% by 1990. Since 1978, new nuclear power station has not been ordered, and some of the contracted power stations were canceled. The atomic energy industry in the United States prospered at the beginning of 1970s, but lost the spirit now, mainly due to the institutional problems rather than the technical ones. As the policy of the government to eliminate the obstacles, the improvement of the procedure for the permission and approval, the establishment of waste disposal capability, the verification of fast breeder reactor technology and the promotion of commercial fuel reprocessing were proposed. The re-establishment of the United States as the reliable supplier of atomic energy service is the final aim. (Kako, I.)

Lie Superalgebras

CERN Document Server

Papi, Paolo; Advances in Lie Superalgebras

2014-01-01

The volume is the outcome of the conference "Lie superalgebras," which was held at the Istituto Nazionale di Alta Matematica, in 2012. The conference gathered many specialists in the subject, and the talks held provided comprehensive insights into the newest trends in research on Lie superalgebras (and related topics like vertex algebras, representation theory and supergeometry). The book contains contributions of many leading esperts in the field and provides a complete account of the newest trends in research on Lie Superalgebras.

Impact parameter selected nuclear temperatures of hot nuclei from excited state populations for 40Ar+197Au reactions at E/A=25MeV

International Nuclear Information System (INIS)

Li Zuyu; He Zhiyong; Duan Limin; Jin Genming; Wu Heyu; Zhang Baoguo; Wen Wanxin; Qi Yujin; Luo Qingzheng; Dai Guangxi; Wang Hongwei

1997-01-01

Nuclear temperatures extracted from excited state populations were measured as a function of linear momentum transfer (LMT) for 40 Ar+ 197 Au reactions at 25MeV/nucleon. The emission temperatures increased slightly with increasing linear momentum transfer or decreasing impact parameter. Taking into account the corrections of detection efficiency and sequential feeding from higher-lying states, a temperature of T∼4MeV was deduced for central collisions. For peripheral collisions the extracted temperatures increased with the energy of the particles. (orig.)

Vibrational circular dichroism spectroscopy of a spin-triplet bis-(biuretato) cobaltate(III) coordination compound with low-lying electronic transitions

DEFF Research Database (Denmark)

Johannessen, Christian; Thulstrup, Peter W.

2007-01-01

. The spectroscopic results were compared to measurements performed on the free ligand and to theoretical calculations using density functional theory (B3LYP/TZVP). The results of the VCD analysis of the coordination compound identified an electronic, dipole-forbidden, magnetic dipole-allowed low-lying d-d transition...

Nuclear phenomena in low-energy nuclear reaction research.

Science.gov (United States)

Krivit, Steven B

2013-09-01

This is a comment on Storms E (2010) Status of Cold Fusion, Naturwissenschaften 97:861-881. This comment provides the following remarks to other nuclear phenomena observed in low-energy nuclear reactions aside from helium-4 make significant contributions to the overall energy balance; and normal hydrogen, not just heavy hydrogen, produces excess heat.

Effect of the ground state correlations in the density distribution and zero point fluctuations

International Nuclear Information System (INIS)

Barranco, F.; Broglia, R.A.

1985-01-01

The existence of collective vibrations in the spectrum implies that the description of the ground state in an independent particle model must be corrected. This is because of the zero point fluctuations induced by the collective vibrations, so that ground state correlations have to be included. These are taken into account via the diagrammatic expansion of the Nuclear Field Theory, giving place to a renormalization in the different properties of the ground state. As far as the density distribution is concerned, in a NFT consistent calculation, the largest contributions arise from diagrams that cannot be expressed in terms of backward going amplitudes of the phonon RPA wave function. For a given multipolarity the main correction comes from the low lying state. The giant resonance is of smaller relevance since it lies at larger energies in the response function. The octupole modes give the dominant contribution, and the effect in average becomes smaller as the multipolarity increases. These results agree quite well with those obtained taking into account the zero point fluctuations of the nuclear surface in the collective model with the Esbensen and Bertsch prescription, which the authors use to explain the anomalous behaviour of the mean square radii of the Calcium isotopes

Motivation and Consequences of Lying. A Qualitative Analysis of Everyday Lying

Directory of Open Access Journals (Sweden)

Beata Arcimowicz

2015-09-01

Full Text Available This article presents findings of qualitative analysis of semi-structured interviews with a group of "frequent liars" and another of "rare liars" who provided their subjective perspectives on the phenomenon of lying. Participants in this study previously had maintained a diary of their social interactions and lies over the course of one week, which allowed to assign them to one of the two groups: frequent or rare liars. Thematic analysis of the material followed by elements of theory formulation resulted in an extended lying typology that includes not only the target of the lie (the liar vs. other but also the motivation (protection vs. bringing benefits. We offer an analysis of what prevents from telling the truth, i.e. penalties, relationship losses, distress of the lied-to, and anticipated lack of criticism for telling the truth. We also focus on understanding moderatorsof consequences of lying (significance of the area of life, the type of lie and capacity to understand the liar that can be useful in future studies. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1503318

Chiral SU(3) dynamics and antikaon-nuclear quasibound states

International Nuclear Information System (INIS)

Weise, W.; Haertle, R.

2008-01-01

Recent developments are summarised concerning low-energy K-bar N interactions as they relate to the possible existence of antikaon-nuclear quasibound states. An exploratory study of antikaons bound to finite nuclei is performed, with emphasis on the evolution of such states from light to heavy nuclei (A = 16-208). The energy dependent, driving attractive K-bar N interactions are constructed using the s-wave coupled-channel amplitudes involving the Λ(1405) and resulting from chiral SU(3) dynamics, plus p-wave amplitudes dominated by the Σ(1385). Effects of Pauli and short-range correlations are discussed. The decay width induced by K - NN two-body absorption is estimated and found to be substantial. It is concluded that K-bar-nuclear quasibound states can possibly exist with binding energies ranging from 60 to 100 MeV, but with short life times corresponding to decay widths of similar magnitudes

The GSAM software: A global search algorithm of minima exploration for the investigation of low lying isomers of clusters

Energy Technology Data Exchange (ETDEWEB)

Marchal, Rémi; Carbonnière, Philippe; Pouchan, Claude [Université de Pau et des Pays de l' Adour, IPREM/ECP, UMR CNRS 5254 (France)

2015-01-22

The study of atomic clusters has become an increasingly active area of research in the recent years because of the fundamental interest in studying a completely new area that can bridge the gap between atomic and solid state physics. Due to their specific properties, such compounds are of great interest in the field of nanotechnology [1,2]. Here, we would present our GSAM algorithm based on a DFT exploration of the PES to find the low lying isomers of such compounds. This algorithm includes the generation of an intial set of structure from which the most relevant are selected. Moreover, an optimization process, called raking optimization, able to discard step by step all the non physically reasonnable configurations have been implemented to reduce the computational cost of this algorithm. Structural properties of Ga{sub n}Asm clusters will be presented as an illustration of the method.

Numerical study of ground state and low lying excitations of quantum antiferromagnets

International Nuclear Information System (INIS)

Trivedi, N.; Ceperley, D.M.

1989-01-01

The authors have studied, via Green function Monte Carlo (GFMC), the S = 1/2 Heisenberg quantum antiferromagnet in two dimensions on a square lattice. They obtain the ground state energy with only statistical errors E 0 /J = -0.6692(2), the staggered magnetization m † = 0.31(2), and from the long wave length behavior of the structure factor, the spin wave velocity c/c o = 1.14(5). They show that the ground state wave function has long range pair correlations arising from the zero point motion of spin waves

Nuclear spin state-resolved cavity ring-down spectroscopy diagnostics of a low-temperature H3+ -dominated plasma

International Nuclear Information System (INIS)

Hejduk, Michal; Dohnal, Petr; Varju, Jozef; Rubovič, Peter; Plašil, Radek; Glosík, Juraj

2012-01-01

We have applied a continuous-wave near-infrared cavity ring-down spectroscopy method to study the parameters of a H 3 + -dominated plasma at temperatures in the range 77–200 K. We monitor populations of three rotational states of the ground vibrational state corresponding to para and ortho nuclear spin states in the discharge and the afterglow plasma in time and conclude that abundances of para and ortho states and rotational temperatures are well defined and stable. The non-trivial dependence of a relative population of para- H 3 + on a relative population of para-H 2 in a source H 2 gas is described. The results described in this paper are valuable for studies of state-selective dissociative recombination of H 3 + ions with electrons in the afterglow plasma and for the design of sources of H 3 + ions in a specific nuclear spin state. (paper)

Nuclear spin state-resolved cavity ring-down spectroscopy diagnostics of a low-temperature H_3^+ -dominated plasma

Science.gov (United States)

Hejduk, Michal; Dohnal, Petr; Varju, Jozef; Rubovič, Peter; Plašil, Radek; Glosík, Juraj

2012-04-01

We have applied a continuous-wave near-infrared cavity ring-down spectroscopy method to study the parameters of a H_3^+ -dominated plasma at temperatures in the range 77-200 K. We monitor populations of three rotational states of the ground vibrational state corresponding to para and ortho nuclear spin states in the discharge and the afterglow plasma in time and conclude that abundances of para and ortho states and rotational temperatures are well defined and stable. The non-trivial dependence of a relative population of para- H_3^+ on a relative population of para-H2 in a source H2 gas is described. The results described in this paper are valuable for studies of state-selective dissociative recombination of H_3^+ ions with electrons in the afterglow plasma and for the design of sources of H_3^+ ions in a specific nuclear spin state.

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

Lie-Nambu and Lie-Poisson structures in linear and nonlinear quantum mechanics

International Nuclear Information System (INIS)

Czachor, M.

1996-01-01

Space of density matrices in quantum mechanics can be regarded as a Poisson manifold with the dynamics given by certain Lie-Poisson bracket corresponding to an infinite dimensional Lie algebra. The metric structure associated with this Lie algebra is given by a metric tensor which is not equivalent to the Cartan-Killing metric. The Lie-Poisson bracket can be written in a form involving a generalized (Lie-)Nambu bracket. This bracket can be used to generate a generalized, nonlinear and completely integrable dynamics of density matrices. (author)

Systematics of gamma decay through low-lying vibrational levels of even--even nuclei excited by (p,p') and (n,n') reactions

International Nuclear Information System (INIS)

Koopman, R.P.

1977-01-01

A series of experiments was performed in which gamma-ray spectra were measured, using a Ge(Li) detector, for incident 7 to 26-MeV protons on the even-even vibrational nuclei 56 Fe, 62 Ni, 64 Zn, 108 Pd, 110 Cd, 114 Cd, 116 Cd, 116 Sn, 120 Sn, and 206 Pb, and for incident 14-MeV neutrons on natural Fe, Ni, Zn, Cd, Sn, and Pb. These measurements yielded gamma-ray cross sections from which it was inferred that almost all of the gamma cascades from (p,p') and (n,n') reactions passed down through the first 2 + levels. Consequently, the strength of the 2 + → 0 + gamma transitions were found to be an indirect measure of the (p,p') or (n,n') cross sections. Several types of nuclear model calculations were performed and compared with experimental results. These calculations included coupled-channel calculations to reproduce the direct, collective excitation of the low-lying levels, and statistical plus pre-equilibrium model calculations to reproduce the (p,p') and the (n,n') cross sections for comparison with the 2 + → 0 + gamma measurements. The agreement between calculation and experiment was generally good except at high energies, where pre-equilibrium processes dominate (i.e. around 26-MeV). Here discrepancies between calculations from the two different pre-equilibrium models and between the data and the calculations were found. Significant isospin mixing of T/sub greater than/ into T/sub less than/ states was necessary in order to have the calculations match the data for the (p,p') reactions, up to about 18-MeV

Fukushima, the sacrificed of nuclear

International Nuclear Information System (INIS)

Deleage, Jean-Paul

2011-01-01

After having briefly recalled the circumstances of the Fukushima accident, the author outlines some weaknesses in the reactor vessels (these weaknesses had been hidden), and some lies in the initial communication about the accident. He also presents the underside of Tepco: dis-information campaigns, lies, falsifications, and so on. Then, he notices that nobody has been able to state that hydrogen explosions were unavoidable whereas this issue has been well documented by the Three Mile Island case where these explosions have been prevented to avoid a release of radioactive products in the atmosphere. As it appears that the extent of these releases has been under-assessed (some said that they have been 25 times higher that stated), consequences for the health of Japanese people could be severe. In the next part, the author notices and comments the extension of protest against nuclear in different countries (Germany, Italy, India). This means the French nuclear empire is put into question again, in its various dimensions (energetic, environmental, economic, political, geographical and social). In this respect, the author discusses the content of an issue of Global Chance which addresses the situation of the world nuclear sector, the position of the French nuclear sector (which appears not to be the self-appointed leader), and the issue of risks and safety. In the last part, the author briefly addresses the need, means, and modalities of phasing nuclear within a generation

Advantages of being a nuclear state

International Nuclear Information System (INIS)

Ahmadova, S.

2012-01-01

Full text : Despite of some progress in the field of nuclear non-proliferation regime at the end of the last century, de-facto nuclear countries, and the issues such as Iran's uranium enrichment activities, the nuclear program of the North Korea proves the regime is in deep crisis. Besides, as a result of rapid scientific and technological development the number of enterprises processing raw material is increasing, the import of materials containing uranium and plutonium is becoming easier and reserves and facilities are widely spread in the black market. Unimpeded access to the information and scientific literature on production of nuclear weapons becomes available, organization and purposeful participation in the events related to the nuclear technology increase, the fact of involvement of scholars and engineers from the developed countries is observed. The growth of nuclear reactors amount with the purpose of energy supply increase the demand for enriched uranium and plutonium, and this hampers the protection these substances. Furthermore, the existence of local natural reserves, the state attention to the staff training able to create nuclear weapons, the staff aware of the work with radioactive substances, the programs considering military preparation on the application of nuclear weapons and so on problems directly threaten the non-proliferation regime. Despite the concern on non-proliferation of nuclear weapons expressed by many scholars and officials, the interest and attempts of states in becoming nuclear states always increase. These interests are stipulated by objective and subjective reasons

Lie groups, Lie algebras, and some of their applications

CERN Document Server

Gilmore, Robert

1974-01-01

Lie group theory plays an increasingly important role in modern physical theories. Many of its calculations remain fundamentally unchanged from one field of physics to another, altering only in terms of symbols and the language. Using the theory of Lie groups as a unifying vehicle, concepts and results from several fields of physics can be expressed in an extremely economical way. With rigor and clarity, this text introduces upper-level undergraduate students to Lie group theory and its physical applications.An opening discussion of introductory concepts leads to explorations of the classical

The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

International Nuclear Information System (INIS)

Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H.

2002-01-01

The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H 2 O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction

Role of nuclear couplings in the inelastic excitation of weakly-bound neutron-rich nuclei

Energy Technology Data Exchange (ETDEWEB)

Dasso, C.H. [Niels Bohr Institute, Copenhagen (Denmark); Lenzi, S.M.; Vitturi, A. [Universita di Padova (Italy)

1996-12-31

Much effort is presently devoted to the study of nuclear systems far from the stability line. Particular emphasis has been placed in light systems such as {sup 11}Li, {sup 8}B and others, where the very small binding energy of the last particles causes their density distribution to extend considerably outside of the remaining nuclear core. Some of the properties associated with this feature are expected to characterize also heavier systems in the vicinity of the proton or neutron drip lines. It is by now well established that low-lying concentrations of multipole strength arise from pure configurations in which a peculiar matching between the wavelength of the continuum wavefunction of the particles and the range of the weakly-bound hole states occurs. To this end the authors consider the break-up of a weakly-bound system in a heavy-ion collision and focus attention in the inelastic excitation of the low-lying part of the continuum. They make use of the fact that previous investigations have shown that the multipole response in this region is not of a collective nature and describe their excited states as pure particle-hole configurations. Since the relevant parameter determining the strength distributions is the binding energy of the last bound orbital they find it most convenient to use single-particle wavefunctions generated by a sperical square-well potential with characteristic nuclear dimensions and whose depth has been adjusted to give rise to a situation in which the last occupied neutron orbital is loosely-bound. Spin-orbit couplings are, for the present purpose, ignored. The results of this investigation clearly indicate that nuclear couplings have the predominant role in causing projectile dissociation in many circumstances, even at bombarding energies remarkably below the Coulomb barrier.

Nuclear methods and the nuclear equation of state

CERN Document Server

1999-01-01

The theoretical study of the nuclear equation of state (EOS) is a field of research which deals with most of the fundamental problems of nuclear physics. This book gives an overview of the present status of the microscopic theory of the nuclear EOS. Its aim is essentially twofold: first, to serve as a textbook for students entering the field, by covering the different subjects as exhaustively and didactically as possible; second, to be a reference book for all researchers active in the theory of nuclear matter, by providing a report on the latest developments. Special emphasis is given to the

Report of the State Office for Nuclear Safety on state supervision of nuclear safety of nuclear facilities and radiation protection in 1998

International Nuclear Information System (INIS)

1999-05-01

The legislative basis of the authority of the State Office for Nuclear Safety as the Czech national regulatory body is outlined, its organizational scheme is presented, and the responsibilities of the various departments are highlighted. The operation of major Czech nuclear facilities, including the Dukovany NPP which is in operation and the Temelin NPP which is under construction, is described with respect to nuclear safety. Since the Office's responsibilities also cover radiation protection in the Czech Republic, a survey of ionizing radiation sources and their supervision is given. Other topics include, among other things, nuclear material transport, the state system for nuclear materials accountancy and control, central registries for radiation protection, nuclear waste management, the National Radiation Monitoring Network, personnel qualification and training, emergency planning, legislative activities, international cooperation, and public information. (P.A.)

Theoretical studies of multistep processes, isospin effects in nuclear scattering, and meson and baryon interactions in nuclear physics: [Annual] progress report, May 1, 1986 to April 30, 1987

International Nuclear Information System (INIS)

Madsen, V.A.; Landau, R.H.

1987-01-01

A progress report on a grant from the DOE supporting theoretical studies in nuclear physics at Oregon State University in 1986, 1987 is presented. The research was led by Professors Landau and Madsen and carried out in collaboration with graduate students in Corvallis and scientists at LLNL-Livermore, KFA-Juelich, Purdue University, Florida State University and TRIUMF. The studies included meson exchange current effects deduced from spin observables in p- 3 He scattering, coupled bound and continuum eigenstates in momentum space for kaons and antiprotons, and charge symmetry violation in π scattering from trinucleons. Additional studies included microscopic optical potential calculations, multiple step processes, and differences in neutron and proton multipole matrix elements and transition densities in low lying collective states and in giant resonances

Properties of the low-lying negative parity states in 45Sc

International Nuclear Information System (INIS)

Chevallier, J.; Haas, B.; Schulz, N.; Toulemonde, M.

1975-01-01

The electromagnetic decay of negative parity states in 45 Sc up to an excitation energy of 2107keV have been investigated via the 42 Ca(α,pγ) 45 Sc reaction at a bombarding energy of 10.5MeV. Spin and lifetime of the levels as well as branching and mixing ratios of their decay γ-rays have been obtained from proton-gamma angular correlation measurements. Calculations based on the strong coupling model have been performed. The results are compared with experiment [fr

Strategy of nuclear power in Korea, non-nuclear-weapon state and peaceful use of nuclear power

International Nuclear Information System (INIS)

Nagasaki, Takao

2005-01-01

The nuclear power plant started at Kori in Korea in April, 1978. Korea has carried out development of nuclear power as a national policy. The present capacity of nuclear power plants takes the sixes place in the world. It supplies 42% total power generation. The present state of nuclear power plant, nuclear fuel cycle facility, strategy of domestic production of nuclear power generation, development of next generation reactor and SMART, strategy of export in corporation with industry, government and research organization, export of nuclear power generation in Japan, nuclear power improvement project with Japan, Korea and Asia, development of nuclear power system with nuclear diffusion resistance, Hybrid Power Extraction Reactor System, radioactive waste management and construction of joint management and treatment system of spent fuel in Asia are stated. (S.Y.)

Lectures on Lie groups

CERN Document Server

Hsiang, Wu-Yi

2017-01-01

This volume consists of nine lectures on selected topics of Lie group theory. We provide the readers a concise introduction as well as a comprehensive 'tour of revisiting' the remarkable achievements of S Lie, W Killing, É Cartan and H Weyl on structural and classification theory of semi-simple Lie groups, Lie algebras and their representations; and also the wonderful duet of Cartans' theory on Lie groups and symmetric spaces.With the benefit of retrospective hindsight, mainly inspired by the outstanding contribution of H Weyl in the special case of compact connected Lie groups, we develop the above theory via a route quite different from the original methods engaged by most other books.We begin our revisiting with the compact theory which is much simpler than that of the general semi-simple Lie theory; mainly due to the well fittings between the Frobenius-Schur character theory and the maximal tori theorem of É Cartan together with Weyl's reduction (cf. Lectures 1-4). It is a wonderful reality of the Lie t...

Low temperature nuclear heat

Energy Technology Data Exchange (ETDEWEB)

Kotakorpi, J.; Tarjanne, R. [comps.

1977-08-01

The meeting was concerned with the use of low grade nuclear heat for district heating, desalination, process heat, and agriculture and aquaculture. The sessions covered applications and demand, heat sources, and economics.

Vermont State Briefing Book on low-level radioactive waste management

International Nuclear Information System (INIS)

1981-07-01

The Vermont State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Vermont. The profile is the result of a survey of Nuclear Regulatory Commission licensees in Vermont. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may affect waste management practices in Vermont

Vermont State Briefing Book on low-level radioactive waste management

Energy Technology Data Exchange (ETDEWEB)

1981-07-01

The Vermont State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Vermont. The profile is the result of a survey of Nuclear Regulatory Commission licensees in Vermont. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may affect waste management practices in Vermont.

Connecticut State Briefing Book for low-level radioactive-waste management

International Nuclear Information System (INIS)

1981-06-01

The Connecticut State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Connecticut. The profile is the result of a survey of Nuclear Regulatory Commission licensees in Connecticut. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may affect waste management practices in Connecticut

Low-lying baryon spectrum with two dynamical twisted mass fermions

Energy Technology Data Exchange (ETDEWEB)

Alexandrou, C. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Computation-based Science and Technology Research Center, Cyprus Institute, Nicosia (Cyprus); Baron, R.; Guichon, P. [CEA-Saclay, IRFU/Service de Physique Nucleaire, Gif-sur-Yvette (France); Carbonell, J.; Drach, V. [UJF/CNRS/IN2P3, Grenoble (France). Lab. de Physique Subatomique et Cosmologie; Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Korzec, T. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Pene, O. [Paris-11 Univ., 91 - Orsay (France). Lab. de Physique Theorique

2009-10-15

The masses of the low lying baryons are evaluated using two degenerate flavors of twisted mass sea quarks corresponding to pseudo scalar masses in the range of about 270 MeV to 500 MeV. The strange valence quark mass is tuned to reproduce the mass of the kaon in the physical limit. The tree-level Symanzik improved gauge action is employed. We use lattices of spatial size 2.1 fm and 2.7 fm at two values of the lattice spacing with r{sub 0}/a=5.22(2) and r{sub 0}/a=6.61(3). We check for both finite volume and cut-off effects on the baryon masses. We performed a detailed study of the chiral extrapolation of the octet and decuplet masses using SU(2) {chi}PT. The lattice spacings determined using the nucleon mass at the physical point are consistent with the values extracted using the pion decay constant. We examine the issue of isospin symmetry breaking for the octet and decuplet baryons and its dependence on the lattice spacing. We show that in the continuum limit isospin breaking is consistent with zero, as expected. The baryon masses that we find after taking the continuum limit and extrapolating to the physical limit are in good agreement with experiment. (orig.)

Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Chinese Edition)

International Nuclear Information System (INIS)

2014-01-01

The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Arabic Edition)

International Nuclear Information System (INIS)

2014-01-01

The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (Spanish Edition)

International Nuclear Information System (INIS)

2014-01-01

The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objeurity Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit

Objective and Essential Elements of a State's Nuclear Security Regime. Nuclear Security Fundamentals (French Edition)

International Nuclear Information System (INIS)

2014-01-01

The possibility that nuclear material or other radioactive material could be used for criminal purposes or intentionally used in an unauthorized manner cannot be ruled out in the current global situation. States have responded to this risk by engaging in a collective commitment to strengthen the protection and control of such material and to respond effectively to nuclear security events. States have agreed to strengthen existing instruments and have established new international legal instruments to enhance nuclear security worldwide. Nuclear security is fundamental in the management of nuclear technologies and in applications where nuclear material or other radioactive material is used or transported. Through its nuclear security programme, the IAEA supports States to establish, maintain and sustain an effective nuclear security regime. The IAEA has adopted a comprehensive approach to nuclear security. This recognizes that an effective national nuclear security regime builds on: the implementation of relevant international legal instruments; information protection; physical protection; material accounting and control; detection of and response to trafficking in such material; national response plans; and contingency measures. With its Nuclear Security Series, the IAEA aims to assist States in implementing and sustaining such a regime in a coherent and integrated manner. The IAEA Nuclear Security Series comprises: Nuclear Security Fundamentals, which include the objective and essential elements of a State's nuclear security regime; Recommendations; Implementing Guides; and Technical Guidance. Each State carries the full responsibility for nuclear security. Specifically, each State has the responsibility to provide for the security of nuclear material and other radioactive material and their associated facilities and activities; to ensure the security of such material in use, storage, or in transport; to combat illicit trafficking and the inadvertent movement of

A Nuclear Third Party Liability Regime of a Multilateral Nuclear Approaches Framework in the Asian Region

Directory of Open Access Journals (Sweden)

Makiko Tazaki

2014-01-01

Full Text Available There are two primary challenges for establishing nuclear third party liability (TPL regimes within multilateral nuclear approaches (MNA to nuclear fuel cycle facilities in the Asian region. The first challenge is to ensure secure and prompt compensation, especially for transboundary damages, which is also a challenge for a nation-based facility. One possible solution is that in order to share common nuclear TPL principles, all states in the region participate in the same international nuclear TPL convention, such as the Convention on Supplementary Compensation for Nuclear Damage (CSC, with a view to its entry into force in the future. One problem with this approach is that many states in the Asian region need to raise their amount of financial security in order to be able to participate in the CSC. The second challenge lies with the multiple MNA member states and encompasses the question of how decisions are to be made and responsabilities of an installation state are to be shared in case of a nuclear incident. Principally, a host state of the MNA facility takes on this responsibility. However, in certain situations and in agreement with all MNA member states, such responsibilities can be indirectly shared among all MNA member states. This can be done through internal arrangements within the MNA framework, such as reimbursement to a host state based on pre-agreed shares in accordance with investment and/or making deposits on such reimbursements in case of an incident.

The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

Energy Technology Data Exchange (ETDEWEB)

Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H. [The University of Illinois, Urbana (United States)

2002-05-01

The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H{sub 2}O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction.

Nuclear Legislation in OECD and NEA Countries. Regulatory and Institutional Framework for Nuclear Activities - United States

International Nuclear Information System (INIS)

2015-01-01

This country profile provide comprehensive information on the regulatory and Institutional Framework governing nuclear activities as well as a detailed review of a full range of nuclear law topics, including: mining regime; radioactive substances; nuclear installations; trade in nuclear materials and equipment; radiation protection; radioactive waste management; non-proliferation and physical protection; transport; and nuclear third party liability. The profile is complemented by reproductions of the primary legislation regulating nuclear activities in the country. Content: I. General Regulatory Regime: 1. Introduction; 2. Mining regime; 3. Radioactive substances, nuclear fuel and equipment (Special nuclear material; Source material; By-product material; Agreement state programmes); 4. Nuclear installations (Initial licensing; Operation and inspection, including nuclear safety; Operating licence renewal; Decommissioning; Emergency response); 5. Radiological protection (Protection of workers; Protection of the public); 6. Radioactive waste management (High-level waste; Low-level waste; Disposal at sea; Uranium mill tailings; Formerly Utilized Sites Remedial Action Program - FUSRAP); 7. Non-proliferation and exports (Exports of source material, special nuclear material, production or utilisation facilities and sensitive nuclear technology; Exports of components; Exports of by-product material; Exports and imports of radiation sources; Conduct resulting in the termination of exports or economic assistance; Subsequent arrangements; Technology exports; Information and restricted data); 8. Nuclear security; 9. Transport; 10. Nuclear third party liability; II. Institutional Framework: 1. Regulatory and supervisory authorities (Nuclear Regulatory Commission - NRC; Department of Energy - DOE; Department of Labor - DOL; Department of Transportation - DOT; Environmental Protection Agency - EPA); 2. Public and semi-public agencies: A. Cabinet-level departments (Department of

Lie-admissible structure of Hamilton's original equations with external terms

International Nuclear Information System (INIS)

Santilli, R.M.

1991-09-01

As a necessary additional step in preparation of our operator studies of closed nonhamiltonian systems, in this note we consider the algebraic structure of the original equations proposed by Lagrange and Hamilton, those with external terms representing precisely the contact nonpotential forces of the interior dynamical problem. We show that the brackets of the theory violate the conditions to characterize any algebra. Nevertheless, when properly written, they characterize a covering of the Lie-isotopic algebras called Lie-admissible algebras. It is indicated that a similar occurrence exists for conventional operator treatments, e.g. for nonconservative nuclear cases characterized by nonhermitean Hamiltonians. This occurrence then prevents a rigorous treatment of basic notions, such as that of angular momentum and spin spin, which are centrally dependent on the existence of a consistent algebraic structure. The emergence of the Lie-admissible algebras is therefore expected to be unavoidable for any rigorous operator treatment of open systems with nonlinear, nonlocal and nonhamiltonian external forces. (author). 14 refs, 1 fig

On the intersection of irreducible components of the space of finite-dimensional Lie algebras

International Nuclear Information System (INIS)

Gorbatsevich, Vladimir V

2012-01-01

The irreducible components of the space of n-dimensional Lie algebras are investigated. The properties of Lie algebras belonging to the intersection of all the irreducible components of this kind are studied (these Lie algebras are said to be basic or founding Lie algebras). It is proved that all Lie algebras of this kind are nilpotent and each of these Lie algebras has an Abelian ideal of codimension one. Specific examples of founding Lie algebras of arbitrary dimension are described and, to describe the Lie algebras in general, we state a conjecture. The concept of spectrum of a Lie algebra is considered and some of the most elementary properties of the spectrum are studied. Bibliography: 6 titles.

State of Nevada, Agency for Nuclear Projects/Nuclear Waste Project Office narrative report, January 1992

International Nuclear Information System (INIS)

1992-01-01

The Agency for Nuclear Projects/Nuclear Waste Project Office (NWPO) is the State of Nevada agency designated by State law to monitor and oversee US Department of Energy (DOE) activities relative to the possible siting, construction, operation and closure of a high-level nuclear waste repository at Yucca Mountain and to carry out the State of Nevada's responsibilities under the Nuclear Waste Policy Act of 1982. During the reporting period the NWPO continued to work toward the five objectives designed to implement the Agency's oversight responsibilities: (1) Assure that the health and safety of Nevada's citizens are adequately protected with regard to any federal high-level radioactive waste program within the State; (2) Take the responsibilities and perform the duties of the State of Nevada as described in the Nuclear Waste Policy Act of 1982 (Public Law 97-425) and the Nuclear Waste Policy Amendments Act of 1987; (3) Advise the Governor, the State Commission on Nuclear Projects and the Nevada State Legislature on matters concerning the potential disposal of high-level radioactive waste in the State; (4) Work closely and consult with affected local governments and State agencies; (5) Monitor and evaluate federal planning and activities regarding high-level radioactive waste disposal. Plan and conduct independent State studies regarding the proposed repository

Theoretical studies of multistep processes, isospin effects in nuclear scattering, and meson and baryon interactions in nuclear physics. Final technical report, 1 September 1979-30 April 1986

International Nuclear Information System (INIS)

Madsen, V.A.; Landau, R.H.

1986-01-01

Final technical report on a contract supporting theoretical studies in nuclear physics at Oregon State University is presented. The research was led by Professors Landau and Madsen and carried out in collaboration with graduate students in Corvallis and scientists at LLNL-Livermore, KFA-Julich, Purdue University-West Lafayette, University of Oregon-Eugene, Florida State University-Talahasie, and TRIUMF-Vancouver. The studies included meson exchange current effects, quark effects,and relativistic/Dirac effects deduced from spin observables in p- 3 He scattering, coupled bound and continuum eigenstates in momentum space for kaons and antiprotons, and charge symmetry violation in π scattering from trinucleons. Additional studies included microscopic optical potential calculations, multiple step processes, and differences in neutron and proton multipole matrix elements in low lying collective states and in giant resonances. 45 refs

Minnesota State Briefing Book on low-level radioactive waste management

International Nuclear Information System (INIS)

1981-07-01

The Minnesota State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Minnesota. The profile is the result of a survey of Nuclear Regulatory Commission licensees in Minnesota conducted by the Minnesota Department of Health. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may affect waste management practices in Minnesota

Low Energy Nuclear Reactions: 2007 Update

Science.gov (United States)

Krivit, Steven B.

2007-03-01

This paper presents an overview of low energy nuclear reactions, a subset of the field of condensed matter nuclear science. Condensed matter nuclear science studies nuclear effects in and/or on condensed matter, including low energy nuclear reactions, an entirely new branch of science that gained widespread attention and notoriety beginning in 1989 with the announcement of a previously unrecognized source of energy by Martin Fleischmann and Stanley Pons that came to be known as cold fusion. Two branches of LENR are recognized. The first includes a set of reactions like those observed by Fleischmann and Pons that use palladium and deuterium and yield excess heat and helium-4. Numerous mechanisms have been proposed to explain these reactions, however there is no consensus for, or general acceptance of, any of the theories. The claim of fusion is still considered speculative and, as such, is not an ideal term for this work. The other branch is a wide assortment of nuclear reactions that may occur with either hydrogen or deuterium. Anomalous nuclear transmutations are reported that involve light as well as heavy elements. The significant questions that face this field of research are: 1) Are LENRs a genuine nuclear reaction? 2) If so, is there a release of excess energy? 3) If there is, is the energy release cost-effective?

Lying in business : Insights from Hanna Arendt's 'Lying in Politics'

NARCIS (Netherlands)

Eenkhoorn, P.; Graafland, J.J.

2011-01-01

The political philosopher Hannah Arendt develops several arguments regarding why truthfulness cannot be counted among the political virtues. This article shows that similar arguments apply to lying in business. Based on Hannah Arendt's theory, we distinguish five reasons why lying is a structural

Experimental efforts at NIST towards one-electron ions in circular Rydberg states

International Nuclear Information System (INIS)

Tan, Joseph N; Guise, Nicholas D; Brewer, Samuel M

2011-01-01

Experimental effort is underway at NIST to enable tests of theory with one-electron ions synthesized in circular Rydberg states from captured bare nuclei. Problematic effects that limit the accuracy of predicted energy levels for low-lying states are vanishingly small for high-angular-momentum (high-L) states; in particular, the nuclear size correction for high-L states is completely negligible for any foreseeable improvement of measurement precision. As an initial step towards realizing such states, highly charged ions are extracted from the NIST electron beam ion trap (EBIT) and steered through the electrodes of a Penning trap. The goal is to capture bare nuclei in the Penning trap for experiments to make one-electron atoms in circular Rydberg states with dipole (E1) transitions in the optical domain accessible to a frequency comb.

Statistical methods in nuclear theory

International Nuclear Information System (INIS)

Shubin, Yu.N.

1974-01-01

The paper outlines statistical methods which are widely used for describing properties of excited states of nuclei and nuclear reactions. It discusses physical assumptions lying at the basis of known distributions between levels (Wigner, Poisson distributions) and of widths of highly excited states (Porter-Thomas distribution, as well as assumptions used in the statistical theory of nuclear reactions and in the fluctuation analysis. The author considers the random matrix method, which consists in replacing the matrix elements of a residual interaction by random variables with a simple statistical distribution. Experimental data are compared with results of calculations using the statistical model. The superfluid nucleus model is considered with regard to superconducting-type pair correlations

Nuclear equation of state for core-collapse supernova simulations with realistic nuclear forces

Energy Technology Data Exchange (ETDEWEB)

Togashi, H., E-mail: hajime.togashi@riken.jp [Nishina Center for Accelerator-Based Science, Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Nakazato, K. [Faculty of Arts and Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Takehara, Y.; Yamamuro, S.; Suzuki, H. [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda, Chiba 278-8510 (Japan); Takano, M. [Research Institute for Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Department of Pure and Applied Physics, Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan)

2017-05-15

A new table of the nuclear equation of state (EOS) based on realistic nuclear potentials is constructed for core-collapse supernova numerical simulations. Adopting the EOS of uniform nuclear matter constructed by two of the present authors with the cluster variational method starting from the Argonne v18 and Urbana IX nuclear potentials, the Thomas–Fermi calculation is performed to obtain the minimized free energy of a Wigner–Seitz cell in non-uniform nuclear matter. As a preparation for the Thomas–Fermi calculation, the EOS of uniform nuclear matter is modified so as to remove the effects of deuteron cluster formation in uniform matter at low densities. Mixing of alpha particles is also taken into account following the procedure used by Shen et al. (1998, 2011). The critical densities with respect to the phase transition from non-uniform to uniform phase with the present EOS are slightly higher than those with the Shen EOS at small proton fractions. The critical temperature with respect to the liquid–gas phase transition decreases with the proton fraction in a more gradual manner than in the Shen EOS. Furthermore, the mass and proton numbers of nuclides appearing in non-uniform nuclear matter with small proton fractions are larger than those of the Shen EOS. These results are consequences of the fact that the density derivative coefficient of the symmetry energy of our EOS is smaller than that of the Shen EOS.

Nuclear ground state

International Nuclear Information System (INIS)

Negele, J.W.

1975-01-01

The nuclear ground state is surveyed theoretically, and specific suggestions are given on how to critically test the theory experimentally. Detailed results on 208 Pb are discussed, isolating several features of the charge density distributions. Analyses of 208 Pb electron scattering and muonic data are also considered. 14 figures

IAEA Completes Nuclear Security Review Mission in United States

International Nuclear Information System (INIS)

2013-01-01

Full text: A team of nuclear security experts led by the International Atomic Energy Agency (IAEA) today completed a mission to review nuclear security practices of civil nuclear facilities licensed by the United States Nuclear Regulatory Commission (NRC). Conducted at the U.S. Government's request, the two-week International Physical Protection Advisory Service (IPPAS) mission reviewed the United States' nuclear security-related legislative and regulatory framework. As part of this work, the IPPAS team, led by John O'Dacre of Canada and comprising nine experts from eight IAEA Member States, met with NRC officials and reviewed the physical protection systems at the Center for Neutron Research (NCNR) at the National Institute of Standards and Technology. The IPPAS team concluded that nuclear security within the U.S. civil nuclear sector is robust and sustainable and has been significantly enhanced in recent years. The team identified a number of good practices in the nation's nuclear security regime and at the NCNR. The IPPAS team also made a recommendation and some suggestions for the continuing improvement of nuclear security overall. The mission in the United States was the 60th IPPAS mission organized by the IAEA. 'Independent international peer reviews such as IAEA IPPAS missions are increasingly being recognized for their value as a key component for exchanges of views and advice on nuclear security measures', said Khammar Mrabit, Director of the IAEA Office of Nuclear Security. 'The good practices identified during this mission will contribute to the continuous improvements of nuclear security in other Member States'. The IPPAS team provided a draft report to the NRC and will submit a final report soon. Because it contains security-related information about a specific nuclear site, IPPAS reports are not made public. 'The IPPAS programme gives us a chance to learn from the experience and perspective of our international partners', said NRC Chairman Allison M

Politicians lie, so do I.

Science.gov (United States)

Celse, Jérémy; Chang, Kirk

2017-11-30

This research analyzed whether political leaders make people lie via priming experiments. Priming is a non-conscious and implicit memory effect in which exposure to one stimulus affects the response to another. Following priming theories, we proposed an innovative concept that people who perceive leaders to be dishonest (such as liars) are likely to lie themselves. We designed three experiments to analyze and critically discussed the potential influence of prime effect on lying behavior, through the prime effect of French political leaders (including general politicians, presidents and parties). Experiment 1 discovered that participants with non-politician-prime were less likely to lie (compared to politician-prime). Experiment 2A discovered that, compared to Hollande-prime, Sarkozy-prime led to lying behavior both in gravity (i.e., bigger lies) and frequency (i.e., lying more frequently). Experiment 2B discovered that Republicans-prime yielded an impact on more lying behavior, and Sarkozy-prime made such impact even stronger. Overall, the research findings suggest that lying can be triggered by external influencers such as leaders, presidents and politicians in the organizations. Our findings have provided valuable insights into organizational leaders and managers in their personnel management practice, especially in the intervention of lying behavior. Our findings also have offered new insights to explain non-conscious lying behavior.

Extension of responsibilities of the State Office for Nuclear Safety

International Nuclear Information System (INIS)

Hrehor, M.

1995-01-01

The responsibilities of the State Office for Nuclear Safety have been extended by Act No. 85/1995 to cover protection against ionizing radiation. The following responsibilities of the State Office for Nuclear Safety are defined by the Act: a) state surveillance over nuclear safety of nuclear facilities, and over radioactive waste and spent fuel management; b) state surveillance over nuclear materials, their record-keeping and accountancy; c) state surveillance over the safeguarding of nuclear facilities and nuclear materials; d) state surveillance over selected materials, facilities and technologies used in the nuclear field, as well as dual-purpose materials and facilities; e) state surveillance over protection against ionizing radiation; f) coordination of the performance of the Radiation Monitoring Network over the Czech Republic and responsibility for international exchange of data on the radiological situation. The Act is reproduced in full, and the organizational structure of the Office is shown in a chart. (J.B.)

Study of the γ decay of high-lying states in 208Pb via inelastic scattering of 17O ions

Directory of Open Access Journals (Sweden)

Crespi F.C.L.

2014-03-01

Full Text Available A measurement of the high-lying states in 208Pb has been made using 17O beams at 20 MeV/u. The gamma decay following inelastic excitation was measured with the detector system AGATA Demonstrator based on segmented HPGe detectors, coupled to an array of large volume LaBr3:Ce scintillators and to an array of Si detectors. Preliminary results in comparison with (γ,γ’ data, for states in the 5-8 MeV energy interval, are presented.

Relativistic configuration interaction calculation on the ground and excited states of iridium monoxide

International Nuclear Information System (INIS)

Suo, Bingbing; Yu, Yan-Mei; Han, Huixian

2015-01-01

We present the fully relativistic multi-reference configuration interaction calculations of the ground and low-lying excited electronic states of IrO for individual spin-orbit component. The lowest-lying state is calculated for Ω = 1/2, 3/2, 5/2, and 7/2 in order to clarify the ground state of IrO. Our calculation suggests that the ground state is of Ω = 1/2, which is highly mixed with 4 Σ − and 2 Π states in Λ − S notation. The two low-lying states 5/2 and 7/2 are nearly degenerate with the ground state and locate only 234 and 260 cm −1 above, respectively. The equilibrium bond length 1.712 Å and the harmonic vibrational frequency 903 cm −1 of the 5/2 state are close to the experimental measurement of 1.724 Å and 909 cm −1 , which suggests that the 5/2 state should be the low-lying state that contributes to the experimental spectra. Moreover, the electronic states that give rise to the observed transition bands are assigned for Ω = 5/2 and 7/2 in terms of the obtained excited energies and oscillator strengths

Study of special challenges for NDT-methods on nuclear structures

Energy Technology Data Exchange (ETDEWEB)

Maack, Stefan; Wiggenhauser, Herbert [BAM Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany); Thunell, Bjoern [Scanscot Technology AB, Lund (Sweden)

2015-07-01

The special design of buildings, constructed for nuclear power plants is a particular challenge for the nondestructive testing in the building industry. In particular the major component thicknesses, the degree of reinforcement and surface coating systems make the application of NDT methods difficult. The studies first steps were undertaken to determine to which extent established applications of these techniques are useable in the field of infrastructure buildings. Methods have been evaluated that are already state of the art. So for example the ground penetrating radar was used for locating metallic mounting parts. Furthermore, the low-lying internal structure of the containment was investigated with the ultrasonic method.

Simple configurations in the capture state and the general picture of nuclear state complications

International Nuclear Information System (INIS)

Soloviev, V.G.

1975-01-01

It is asserted that the effective nuclear forces and the methods of solving the many-body problem may serve as a basis for describing states of low, intermediate and high excitation energy. It is indicated that it is important to study nuclear structure complications with increasing excitation energy and fragmentation of single particle and many-particle states. The foundations of the model for describing fragmentation which is based on the account of the quadiparticle-phonon interaction are presented. The results of calculations of fragmentation for the (631)(spin down),(620)(spin up), (640)(spin up) and (600)(spin up) one-quasiparticle states in 239 U are given. It is shown that the state strength is distributed over a wide energy interval, the distribution maximum is shifted down with respect to the single-particle energy. The degree of fragmentation is shown to depend strongly on the position of the single-particle level with respect to the Fermi level. A modified version of the model is given for treating highly excited states of the type of giant resonances and for studying their influence on the structure of states of intermediate excitation energy. The general assumptions of the approach based on the operator form of the wave function of highly excited states are presented, and the contribution of individual simple configurations to the neutron resonance wave functions is estimated. It is shown in which case the valence neutron can be employed. The compound-state structure is discussed. (Auth.)

Low-level radioactive waste disposal technologies used outside the United States

International Nuclear Information System (INIS)

Templeton, K.J.; Mitchell, S.J.; Molton, P.M.; Leigh, I.W.

1994-01-01

Low-level radioactive waste (LLW) disposal technologies are an integral part of the waste management process. In the United States, commercial LLW disposal is the responsibility of the State or groups of States (compact regions). The United States defines LLW as all radioactive waste that is not classified as spent nuclear fuel, high- level radioactive waste, transuranic waste, or by-product material as defined in Section II(e)(2) of the Atomic Energy Act. LLW may contain some long-lived components in very low concentrations. Countries outside the United States, however, may define LLW differently and may use different disposal technologies. This paper outlines the LLW disposal technologies that are planned or being used in Canada, China, Finland, France, Germany, Japan, Sweden, Taiwan, and the United Kingdom (UK)

Assessing the optimism-pessimism debate: Nuclear proliferation, nuclear risks, and theories of state action

International Nuclear Information System (INIS)

Busch, Nathan Edward

2001-01-01

This dissertation focuses on the current debate in international relations literature over the risks associated with the proliferation of nuclear weapons. On this subject, IR scholars are divided into roughly two schools: proliferation 'optimists,' who argue that proliferation can be beneficial and that its associated hazards are at least surmountable, and proliferation 'pessimists,' who believe the opposite. This debate centers upon a theoretical disagreement about how best to explain and predict the behavior of states. Optimists generally ground their arguments on rational deterrence theory and maintain that nuclear weapons can actually increase stability among states, while pessimists often ground their arguments on 'organization theory,' which contends that organizational, bureaucratic, and other factors prevent states from acting rationally. A major difficulty with the proliferation debate, however, is that both sides tend to advance their respective theoretical positions without adequately supporting them with solid empirical evidence. This dissertation detailed analyses of the nuclear programs in the United States, Russia, China, India, and Pakistan to determine whether countries with nuclear weapons have adequate controls over their nuclear arsenals and tissue material stockpiles (such as highly enriched uranium and plutonium). These case studies identify the strengths and weaknesses of different systems of nuclear controls and help predict what types of controls proliferating states are likely to employ. On the basis of the evidence gathered from these cases, this dissertation concludes that a further spread of nuclear weapons would tend to have seriously negative effects on international stability by increasing risks of accidental, unauthorized, or inadvertent use of nuclear weapons and risks of thefts of fissile materials for use in nuclear or radiological devices by aspiring nuclear states or terrorist groups. (author)

Low-temperature nuclear orientation

International Nuclear Information System (INIS)

Stone, N.J.; Postma, H.

1986-01-01

This book comprehensively surveys the many aspects of the low temperature nuclear orientation method. The angular distribution of radioactive emissions from nuclei oriented by hyperfine interactions in solids, is treated experimentally and theoretically. A general introductory chapter is followed by formal development of the theory of the orientation process and the anisotropic emission of decay products from oriented nuclei, applied to radioactive decay and to reactions. Five chapters on applications to nuclear physics cover experimental studies of alpha, beta and gamma emission, nuclear moment measurement and level structure information. Nuclear orientation studies of parity non-conservation and time reversal asymmetry are fully described. Seven chapters cover aspects of hyperfine interactions, magnetic and electric, in metals, alloys and insulating crystals, including ordered systems. Relaxation phenomena and the combined technique of NMR detection using oriented nuclei are treated at length. Chapters on the major recent development of on-line facilities, giving access to short lived nuclei far from stability, on the use of nuclear orientation for thermometry below 1 Kelvin and on technical aspects of the method complete the main text. Extensive appendices, table of relevant parameters and over 1000 references are included to assist the design of future experiments. (Auth.)

Shutdown and low-power operation at commercial nuclear power plants in the United States

International Nuclear Information System (INIS)

1993-09-01

The report contains the results of the NRC Staff's evaluation of shutdown and low-power operations at US commercial nuclear power plants. The report describes studies conducted by the staff in the following areas: Operating experience related to shutdown and low-power operations, probabilistic risk assessment of shutdown and low-power conditions and utility programs for planning and conducting activities during periods the plant is shut down. The report also documents evaluations of a number of technical issues regarding shutdown and low-power operations performed by the staff, including the principal findings and conclusions. Potential new regulatory requirements are discussed, as well as potential changes in NRC programs. A draft report was issued for comment in February 1992. This report is the final version and includes the responses to the comments along with the staff regulatory analysis of potential new requirements

Spectroscopic Parameter and Molecular Constant Investigations on Low-Lying States of BeF Radical

Directory of Open Access Journals (Sweden)

Jin Feng Sun

2012-02-01

Full Text Available The potential energy curves (PECs of X2Σ+, A2Πr and B2Σ+ states of BeF radical have been investigated using the complete active space self-consistent-field (CASSCF method, followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI approach at the correlation-consistent basis sets, cc-pV5Z for Be and aug-cc-pV6Z for F. Based on the PECs of X2Σ+, A2Πr and B2Σ+ states, the spectroscopic parameters (De, Re, ωe, ωeχe, αe and Be have also been determined in the present work. With the PECs determined at the present level of theory, vibrational states have been predicted for each state when the rotational quantum number J equals zero (J = 0. The vibrational levels, inertial rotation and centrifugal distortion constants are determined for the three states, and the classical turning points are also calculated for the X2Σ+ state. Compared with the available experiments and other theories, it can be seen that the present spectroscopic parameter and molecular constant results are more fully in agreement with the experimental findings.

Development of Risk Assessment Methodology for State's Nuclear Security Regime

International Nuclear Information System (INIS)

Jang, Sung Soon; Seo, Hyung Min; Lee, Jung Ho; Kwak, Sung Woo

2011-01-01

Threats of nuclear terrorism are increasing after 9/11 terrorist attack. Treats include nuclear explosive device (NED) made by terrorist groups, radiological damage caused by a sabotage aiming nuclear facilities, and radiological dispersion device (RDD), which is also called 'dirty bomb'. In 9/11, Al Qaeda planed to cause radiological consequences by the crash of a nuclear power plant and the captured airplane. The evidence of a dirty bomb experiment was found in Afganistan by the UK intelligence agency. Thus, the international communities including the IAEA work substantial efforts. The leaders of 47 nations attended the 2010 nuclear security summit hosted by President Obama, while the next global nuclear summit will be held in Seoul, 2012. Most states established and are maintaining state's nuclear security regime because of the increasing threat and the international obligations. However, each state's nuclear security regime is different and depends on the state's environment. The methodology for the assessment of state's nuclear security regime is necessary to design and implement an efficient nuclear security regime, and to figure out weak points. The IAEA's INPRO project suggests a checklist method for State's nuclear security regime. The IAEA is now researching more quantitative methods cooperatively with several countries including Korea. In this abstract, methodologies to evaluate state's nuclear security regime by risk assessment are addressed

Preliminary development of thermal nuclear cell homogenization code

International Nuclear Information System (INIS)

Su'ud, Z.; Shafii, M. A.; Yudha, S. P.; Waris, A.; Rijal, K.

2012-01-01

Nuclear fuel cell homogenization for thermal reactors usually include three main parts, i.e., fast energy resonance part which usually adopt narrow resonance approximation to treat the resonance, low (intermediate) energy region in which the resonance can not be treated accurately using NR approximation and therefore we should use intermediate resonance treatment, and thermal energy region (very low) in which the effect of thermal must be treated properly. In n this study the application of the intermediate resonance approximation treatment for low energy nuclear resonance is discussed. The method is iterative based. As a sample the method is applied in U-235 low lying resonance and the result is presented and discussed.

The nuclear equation of state

International Nuclear Information System (INIS)

Kahana, S.

1986-01-01

The role of the nuclear equation of state in determining the fate of the collapsing cores of massive stars is examined in light of both recent theoretical advances in this subject and recent experimental measurements with relativistic heavy ions. The difficulties existing in attempts to bring the softer nuclear matter apparently required by the theory of Type II supernovae into consonance with the heavy ion data are discussed. Relativistic mean field theory is introduced as a candidate for derivation of the equation of state, and a simple form for the saturation compressibility is obtained. 28 refs., 4 figs., 1 tab

The nuclear equation of state

Energy Technology Data Exchange (ETDEWEB)

Kahana, S.

1986-01-01

The role of the nuclear equation of state in determining the fate of the collapsing cores of massive stars is examined in light of both recent theoretical advances in this subject and recent experimental measurements with relativistic heavy ions. The difficulties existing in attempts to bring the softer nuclear matter apparently required by the theory of Type II supernovae into consonance with the heavy ion data are discussed. Relativistic mean field theory is introduced as a candidate for derivation of the equation of state, and a simple form for the saturation compressibility is obtained. 28 refs., 4 figs., 1 tab.

Nuclear lifetimes and the slowing down of heavy ions in solids

International Nuclear Information System (INIS)

Scherpenzeel, D.E.C.

1981-01-01

Nuclear lifetime measurements by means of the Doppler Shift Attenuation (DSA) method at low recoil velocities (β approximately less than 0.01) are notoriously difficult due to the observed strong dependence of the extracted lifetimes on the slowing-down material at low initial velocities. This is mainly caused by the lack of reliable stopping power data for these velocities and the absence of an adequate theory to compensate for that. This problem of the determination of the correct mean life for the lowest Jsup(π) = 4 + state of 22 Ne is solved by measurements with the coincident high-velocity DSA method. Excited nuclei of high initial velocity [β(0) approximately 0.05] are generated by the bombardment of light targets, such as 1 H, 2 H, 3 H and 4 He, with beams of heavy ions. The combination of high initial velocity and coincidence restriction offers many advantages over the conventional techniques. The coincident high-velocity DSA method is also used to determine mean lives of low-lying excited states of the silicon isotopes 28 29 30 Si. The observed Doppler patterns are analyzed with experimental stopping powers and the resulting mean lives range from about 25 fs to 4 ps. The mean lives of the first excited state of 18 O and some low-lying levels of 35 S are determined from Doppler patterns analyzed with experimental stopping powers. The present stopping results for O, Si and S ions in Mg are also analyzed in terms of the effective charge concept. It is concluded that at the present level of accuracy of about 5 % the obtained results are consistent with this concept. (Auth.)

Nuclear data and low energy nuclear research in Israel

International Nuclear Information System (INIS)

Yiftah, S.

1977-04-01

The Israel Nuclear Data and Low Energy Nuclear Research relevant to the International Nuclear Data Committee was continued in various institutions. The major experimental facilities consist of: A 5 Megawatt swimming pool enriched uranium reactor at the Soreq Nuclear Research Centre; A 26 Megawatt heavy water tank-type natural uranium reactor at the Negev Research Centre; A 6-million volt EN tandem accelerator at the Weizmann Institute of Science, Rehovot; The new most modern high energy 14 UD pelletron accelerator manufactured by the National Electrostatic Corporation of Middleton, Wisconsin, installed inside the Koffler Accelerator Tower at the Weizmann Institute of Science, Rehovot. Brief abstracts of the research work, both published and unpublished, listed according to the various laboratories, are reported in the following pages. (author)

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

A reactor-level analysis of busbar costs for US nuclear plants, 1970-2005

International Nuclear Information System (INIS)

Koomey, Jonathan; Hultman, Nathan E.

2007-01-01

We present a reactor-by-reactor analysis of historical busbar costs for 99 nuclear reactors in the United States, and compare those costs with recent projections for next-generation US reactors. We argue that cost projections far different from median historical costs require more justification than estimates that lie close to those medians. Our analysis suggests that some recent projections of capital costs, construction duration, and total operations and maintenance costs are quite low-far enough from the historical medians that additional scrutiny may be required to justify using such estimates in current policy discussions and planning

Nuclear Structure Calculations for Two-Neutrino Double-β Decay

Directory of Open Access Journals (Sweden)

P. Sarriguren

2016-01-01

Full Text Available We study the two-neutrino double-β decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-β decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed self-consistent mean field with Skyrme interactions including pairing and spin-isospin residual forces, which are treated in a proton-neutron quasiparticle random-phase approximation. We compare our results for Gamow-Teller strength distributions with experimental information obtained from charge-exchange reactions. We also compare our results for the two-neutrino double-β decay nuclear matrix elements with those extracted from the measured half-lives. Both single-state and low-lying-state dominance hypotheses are analyzed theoretically and experimentally making use of recent data from charge-exchange reactions and β decay of the intermediate nuclei.

Responsibilities of the nuclear-weapon states

International Nuclear Information System (INIS)

Wang Jun

1994-01-01

The responsibilities of Nuclear Weapon States are presented by a straightforward analysis together with the ways in which they could fulfill them. The complete undertaking of all the commitments by the Nuclear Weapon States may take a long time. However they do not have a single excuse to neglect such a historic opportunity to do their best to provide a genuinely secure world environment for the international community, of which they too are members

Experimental study of high spin states in low-medium mass nuclei by use of charge particle induced reactions

International Nuclear Information System (INIS)

Alenius, N.G.

1975-01-01

For the test of nuclear models the study of the properties of nuclear states of high angular momentum is especially important, because such states can often be given very simple theoretical descriptions. High spin states are easily populated by use of reactions initiated by alpha particles or heavy ions. In this thesis a number of low-medium mass nuclei have been studied, with emphasis on high spin states. (Auth.)

Preparation of Act on State Surveillance of Nuclear Safety of Nuclear Installations

International Nuclear Information System (INIS)

Kyncl, J.

1983-01-01

The Czechoslovak Government Decree no. 179 of June 1982 approved the principles underlying the first Czechoslovak legal norm to complexly resolve the problem of State surveillance of nuclear safety of nuclear installations. In the introduction the law will define the concept of nuclear safety of nuclear installations and will justify the reasons for which it has to be assured. The individual parts of the law will deal with the establishment of State surveillance of nuclear safety, the tasks of the Czechoslovak Atomic Energy Commission in this area, the control activity of Commission personnel, the measures taken against responsible organizations and personnel for failing to observe their duties, the obligations of bodies and organizations, and the cooperation between inspection bodies. (A.K.)

Medicine, lies and deceptions.

Science.gov (United States)

Benn, P

2001-04-01

This article offers a qualified defence of the view that there is a moral difference between telling lies to one's patients, and deceiving them without lying. However, I take issue with certain arguments offered by Jennifer Jackson in support of the same conclusion. In particular, I challenge her claim that to deny that there is such a moral difference makes sense only within a utilitarian framework, and I cast doubt on the aptness of some of her examples of non-lying deception. But I argue that lies have a greater tendency to damage trust than does non-lying deception, and suggest that since many doctors do believe there is a moral boundary between the two types of deception, encouraging them to violate that boundary may have adverse general effects on their moral sensibilities.

The need to bring the new global regime of civil nuclear liability to life

International Nuclear Information System (INIS)

McIntosh, St.

2000-01-01

The Chernobyl accident raised consciousness around the world about civil liability issues. People in Australia and elsewhere looked at the existing international nuclear liability regime and concluded that it was inadequate. The amount of compensation available under the regime was too low. The regime did not cover environmental damage. Australia decided to take an active role in the proceedings of the Standing Committee on Nuclear liability. Australia has a favourable judgment on the new Convention on Supplementary Compensation for nuclear damages. It provided for a dedicated fund for transboundary damage, the inclusion of environmental damage, the lion's share of the contributions to the international fund established under the Convention to be borne by nuclear power generating states, jurisdiction over actions concerning nuclear damage from a nuclear accident in a Party's territory or Exclusive Economic Zone to lie with the courts of that Party. It reproaches this Convention for compensable damage to be determined by the law of the competent court, and the necessity of emission of ionizing radiations for the Convention to take effect. (N.C.)

The on-line low temperature nuclear orientation facility NICOLE

International Nuclear Information System (INIS)

Ohtsubo, T; Roccia, S; Gaulard, C; Stone, N J; Stone, J R; Köster, U; Nikolov, J; Veskovic, M; Simpson, G S

2017-01-01

We review major experiments and results obtained by the on-line low temperature nuclear orientation method at the NICOLE facility at ISOLDE, CERN since the year 2000 and highlight their general physical impact. This versatile facility, providing a large degree of controlled nuclear polarization, was used for a long-standing study of magnetic moments at shell closures in the region Z  = 28, N  = 28–50 but also for dedicated studies in the deformed region around A  ∼ 180. Another physics program was conducted to test symmetry in the weak sector and constrain weak coupling beyond V–A . Those two programs were supported by careful measurements of the involved solid state physics parameters to attain the full sensitivity of the technique and provide interesting interdisciplinary results. Future plans for this facility include the challenging idea of measuring the beta–gamma–neutron angular distributions from polarized beta delayed neutron emitters, further test of fundamental symmetries and obtaining nuclear structure data used in medical applications. The facility will also continue to contribute to both the nuclear structure and fundamental symmetry test programs. (paper)

Particle-like structure of Lie algebras

Science.gov (United States)

Vinogradov, A. M.

2017-07-01

If a Lie algebra structure 𝔤 on a vector space is the sum of a family of mutually compatible Lie algebra structures 𝔤i's, we say that 𝔤 is simply assembled from the 𝔤i's. Repeating this procedure with a number of Lie algebras, themselves simply assembled from the 𝔤i's, one obtains a Lie algebra assembled in two steps from 𝔤i's, and so on. We describe the process of modular disassembling of a Lie algebra into a unimodular and a non-unimodular part. We then study two inverse questions: which Lie algebras can be assembled from a given family of Lie algebras, and from which Lie algebras can a given Lie algebra be assembled. We develop some basic assembling and disassembling techniques that constitute the elements of a new approach to the general theory of Lie algebras. The main result of our theory is that any finite-dimensional Lie algebra over an algebraically closed field of characteristic zero or over R can be assembled in a finite number of steps from two elementary constituents, which we call dyons and triadons. Up to an abelian summand, a dyon is a Lie algebra structure isomorphic to the non-abelian 2-dimensional Lie algebra, while a triadon is isomorphic to the 3-dimensional Heisenberg Lie algebra. As an example, we describe constructions of classical Lie algebras from triadons.

Status of nuclear engineering education in the United States

International Nuclear Information System (INIS)

Brown, G.J.

2000-01-01

Nuclear engineering education in the United States is reflective of the perceived health of the nuclear electric power industry within the country. Just as new commercial reactor orders have vanished and some power plants have shut down, so too have university enrollments shrunk and research reactors closed. This decline in nuclear trained specialists and the disappearance of the nuclear infrastructure is a trend that must be arrested and reversed if the United States is to have a workforce capable of caring for a nuclear power industry to not only meet future electric demand but to ensure that the over 100 existing plants, their supporting facilities and their legacy in the form of high level waste and facility clean-up are addressed. Additionally, the United States has an obligation to support and maintain its nuclear navy and other defence needs. And, lastly, if the United States is to have a meaningful role in the international use of nuclear power with regard to safety, non-proliferation and the environment, then it is imperative that the country continues to produce world-class nuclear engineers and scientists by supporting nuclear engineering education at its universities. The continued support of the federal government. and industry for university nuclear engineering and nuclear energy research and development is essential to sustain the nuclear infrastructure in the United States. Even with this support, and the continued excellent operation of the existing fleet of nuclear electric power plants, it is conceivable that nuclear engineering as an academic discipline may fall victim to poor communications and a tarnished public image. What is needed is a combination of federal and industrial support along with the creativity of the universities to expand their offerings to include more than power production. The objective is a positive message on careers in nuclear related fields, and recognition of the important role of nuclear energy in meeting the country

Nuclear dynamical diffraction using synchrotron radiation

Energy Technology Data Exchange (ETDEWEB)

Brown, Dennis Eugene [Stanford Univ., CA (United States)

1993-05-01

The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of ⁵⁷Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2±0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 11/2 natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei.

Nuclear dynamical diffraction using synchrotron radiation

International Nuclear Information System (INIS)

Brown, D.E.

1993-05-01

The scattering of synchrotron radiation by nuclei is extensively explored in this thesis. From the multipole electric field expansion resulting from time-dependent nonrelativistic perturbation theory, a dynamical scattering theory is constructed. This theory is shown, in the many particle limit, to be equivalent to the semi-classical approach where a quantum mechanical scattering amplitude is used in the Maxwell inhomogeneous wave equation. The Moessbauer specimen whose low-lying energy levels were probed is a ferromagnetic lattice of 57 Fe embedded in a yttrium iron garnet (YIG) crystal matrix. The hyperfine fields in YIG thin films were studied at low and room temperature using time-resolved quantum beat spectroscopy. Nuclear hyperfine structure quantum beats were measured using a fast plastic scintillator coincidence photodetector and associated electronics having a time resolution of 2.5 nsec. The variation of the quantum beat patterns near the Bragg [0 0 2] diffraction peak gave a Lamb-Moessbauer factor of 8.2±0.4. Exploring characteristic dynamical features in the higher order YIG [0 0 10] reflection revealed that one of the YIG crystals had bifurcated into two different layers. The dynamics of nuclear superradiance was explored. This phenomenon includes the radiative speedup exhibited by a collective state of particles, and, in striking concurrence, resonance frequency shifts. A speedup of a factor of 4 in the total decay rate and a beat frequency shift of 1 1/2 natural resonance linewidths were observed. Nuclear resonance scattering was also found to be a useful way of performing angular interferometry experiments, and it was used to observe the phase shift of a rotated quantum state. On the whole, nuclear dynamical diffraction theory has superbly explained many of the fascinating features of resonant magnetic dipole radiation scattered by a lattice of nuclei

Binding lies

Directory of Open Access Journals (Sweden)

Avraham eMerzel

2015-10-01

Full Text Available Do we feel bound by our own misrepresentations? Does one act of cheating compel the cheater to make subsequent choices that maintain the false image even at a cost? To answer these questions we employed a two-task paradigm such that in the first task the participants could benefit from false reporting of private observations whereas in the second they could benefit from making a prediction in line with their actual, rather than their previously reported observations. Thus, for those participants who inflated their report during the first task, sticking with that report for the second task was likely to lead to a loss, whereas deviating from it would imply that they had lied. Data from three experiments (total N=116 indicate that, having lied, participants were ready to suffer future loss rather than admit, even if implicitly, that they had lied.

When is a lie acceptable? Work and private life lying acceptance depends on its beneficiary.

Science.gov (United States)

Cantarero, Katarzyna; Szarota, Piotr; Stamkou, Eftychia; Navas, Marisol; Dominguez Espinosa, Alejandra Del Carmen

2018-01-01

In this article we show that when analyzing attitude towards lying in a cross-cultural setting, both the beneficiary of the lie (self vs other) and the context (private life vs. professional domain) should be considered. In a study conducted in Estonia, Ireland, Mexico, The Netherlands, Poland, Spain, and Sweden (N = 1345), in which participants evaluated stories presenting various types of lies, we found usefulness of relying on the dimensions. Results showed that in the joint sample the most acceptable were other-oriented lies concerning private life, then other-oriented lies in the professional domain, followed by egoistic lies in the professional domain; and the least acceptance was shown for egoistic lies regarding one's private life. We found a negative correlation between acceptance of a behavior and the evaluation of its deceitfulness.

Electron-nuclear magnetic resonance in the inverted state

International Nuclear Information System (INIS)

Ignatchenko, V.A.; Tsifrinovich, V.I.

1975-01-01

The paper considers the susceptibility of the electron-nucleus system of a ferromagnet when nuclear magnetization is inverted with respect to the hyperfine field direction. The inverted state is a situation in which nuclear magnetization is turned through π relative to its equilibrium orientation, whereas electron magnetization is in an equilibrium state with respect to an external magnetic field. The consideration is carried out for a thin plate magnetized in its plane. Amplification of a weak radiofrequency signal can be attained under the fulfilment of an additional inequality relating the interaction frequency with electron and nuclear relaxation parameters. The gain may exceed the gain for an inverted nuclear system in magnetically disordered substances. In the range of strong interaction between the frequencies of ferromagnetic (FMR) and nuclear magnetic (NMR) resonances the electron-nuclear magnetic resonance (ENMR) spectrum possesses a fine structure which is inverse to that obtained for the ENMR spectrum in a normal state. The inverted state ENMR line shape is analysed in detail for the case of so weak HF fields that the relaxation conditions may be regarded as stationary. The initial (linear) stages of a forced transient process arising in an electron-nuclear system under the effect of a strong HF field are briefly analysed

Nuclear data and low energy nuclear research in Israel

International Nuclear Information System (INIS)

Yiftah, S.

1978-07-01

The Israel Nuclear Data and Low Energy Nuclear Research relevant to the International Nuclear Data Committee was continued in the various institutions listed in previous Progress Reports (LS-270 for 1976). The latest major experimental facility, the 14 UD pelletron, was installed in the Koffler Accelerator Tower at the Weizmann Institute of Science, Rehovot, and accepted on April 1st 1977. A report in Revue de Physique Appliquee of October 1977 including a description of the facility, acceptance performance, as well as some supplementary devices, is reproduced in the beginning of this report. Brief abstracts of the research work, both published and unpublished, are presented. (author)

Lie bialgebras with triangular decomposition

International Nuclear Information System (INIS)

Andruskiewitsch, N.; Levstein, F.

1992-06-01

Lie bialgebras originated in a triangular decomposition of the underlying Lie algebra are discussed. The explicit formulas for the quantization of the Heisenberg Lie algebra and some motion Lie algebras are given, as well as the algebra of rational functions on the quantum Heisenberg group and the formula for the universal R-matrix. (author). 17 refs

Non-proliferation of nuclear weapons and nuclear security. Overview of safeguards requirements for States with limited nuclear material and activities

International Nuclear Information System (INIS)

Lodding, J.; Ribeiro, B.

2006-06-01

This booklet provides an overview of safeguards obligations that apply to States which are parties to the Nuclear Non-Proliferation Treaty (NPT) that have no nuclear facilities and only limited quantities of nuclear material. Most State parties to the NPT have no nuclear facilities and only limited quantities of nuclear material. For such States, safeguards implementation is expected to be simple and straightforward. This booklet provides an overview of the safeguards obligations that apply to such States. It is hoped that a better understanding of these requirements will facilitate the conclusion and implementation of safeguards agreements and additional protocols, and thereby contribute to the strengthening of the IAEA?s safeguards system and of collective security

Non-proliferation of nuclear weapons and nuclear security. Overview of Safeguards requirements for States with limited nuclear material and activities

International Nuclear Information System (INIS)

Lodding, J.; Ribeiro, B.

2006-06-01

This booklet provides an overview of safeguards obligations that apply to States which are parties to the Nuclear Non-Proliferation Treaty (NPT) that have no nuclear facilities and only limited quantities of nuclear material. Most State parties to the NPT have no nuclear facilities and only limited quantities of nuclear material. For such States, safeguards implementation is expected to be simple and straightforward. This booklet provides an overview of the safeguards obligations that apply to such States. It is hoped that a better understanding of these requirements will facilitate the conclusion and implementation of safeguards agreements and additional protocols, and thereby contribute to the strengthening of the IAEA?s safeguards system and of collective security

Verbal lie detection

NARCIS (Netherlands)

Vrij, Aldert; Taylor, Paul J.; Picornell, Isabel; Oxburgh, Gavin; Myklebust, Trond; Grant, Tim; Milne, Rebecca

2015-01-01

In this chapter, we discuss verbal lie detection and will argue that speech content can be revealing about deception. Starting with a section discussing the, in our view, myth that non-verbal behaviour would be more revealing about deception than speech, we then provide an overview of verbal lie

Nuclear Computational Low Energy Initiative (NUCLEI)

Energy Technology Data Exchange (ETDEWEB)

Reddy, Sanjay K. [University of Washington

2017-08-14

This is the final report for University of Washington for the NUCLEI SciDAC-3. The NUCLEI -project, as defined by the scope of work, will develop, implement and run codes for large-scale computations of many topics in low-energy nuclear physics. Physics to be studied include the properties of nuclei and nuclear decays, nuclear structure and reactions, and the properties of nuclear matter. The computational techniques to be used include Quantum Monte Carlo, Configuration Interaction, Coupled Cluster, and Density Functional methods. The research program will emphasize areas of high interest to current and possible future DOE nuclear physics facilities, including ATLAS and FRIB (nuclear structure and reactions, and nuclear astrophysics), TJNAF (neutron distributions in nuclei, few body systems, and electroweak processes), NIF (thermonuclear reactions), MAJORANA and FNPB (neutrino-less double-beta decay and physics beyond the Standard Model), and LANSCE (fission studies).

Structure-Based Low-Rank Model With Graph Nuclear Norm Regularization for Noise Removal.

Science.gov (United States)

Ge, Qi; Jing, Xiao-Yuan; Wu, Fei; Wei, Zhi-Hui; Xiao, Liang; Shao, Wen-Ze; Yue, Dong; Li, Hai-Bo

2017-07-01

Nonlocal image representation methods, including group-based sparse coding and block-matching 3-D filtering, have shown their great performance in application to low-level tasks. The nonlocal prior is extracted from each group consisting of patches with similar intensities. Grouping patches based on intensity similarity, however, gives rise to disturbance and inaccuracy in estimation of the true images. To address this problem, we propose a structure-based low-rank model with graph nuclear norm regularization. We exploit the local manifold structure inside a patch and group the patches by the distance metric of manifold structure. With the manifold structure information, a graph nuclear norm regularization is established and incorporated into a low-rank approximation model. We then prove that the graph-based regularization is equivalent to a weighted nuclear norm and the proposed model can be solved by a weighted singular-value thresholding algorithm. Extensive experiments on additive white Gaussian noise removal and mixed noise removal demonstrate that the proposed method achieves a better performance than several state-of-the-art algorithms.

Factors in low-carbon energy transformations: Comparing nuclear and bioenergy in Brazil, Sweden, and the United States

International Nuclear Information System (INIS)

Hultman, Nathan E.; Malone, Elizabeth L.; Runci, Paul; Carlock, Gregory; Anderson, Kate L.

2012-01-01

Policies to address climate change by reducing greenhouse gas emissions might be made more effective if we can better understand the pathways by which transformative technologies become significant components of energy systems. Indeed, the central question of mitigation revolves around the scope of policy to influence or accelerate the diffusion of low-carbon technology. While market forces clearly influence technology deployment, understanding the longer-term and large-scale changes in the energy system requires a broader understanding of the relative influence of institutional, behavioral, and social factors. This paper presents the results of an interview-based, comparative case approach to investigating systematically the relative importance of these non-economic factors influencing technological change across technology and country contexts. We identified two low-carbon energy sectors (bioenergy and nuclear power) that underwent significant changes over the past 50 years in the energy portfolio of three countries: Brazil, Sweden, and the United States. We identified nine categories of factors that might contribute to these large technological transformations, and then evaluated, via interviews with sector participants in each country, which factors were viewed as being determinative or highly influential in the trajectory of that technology in their country context. We also draw out policy implications and directions for future research. - Highlights: ► Study of energy transformations in bioenergy and nuclear energy in Brazil, Sweden, and the US. ► Data include survey and 78 interviews across 3 countries and 2 sectors. ► Across all countries and sectors, domestic policy was seen as the major factor in transitions. ► Other key factors with more variance were technological characteristics and industry structure. ► Study adds empirical detail to understanding of relative weights of factors in energy transitions.

Evaluating Russian space nuclear reactor technology for United States applications

International Nuclear Information System (INIS)

Polansky, G.F.; Schmidt, G.L.; Voss, S.S.; Reynolds, E.L.

1994-01-01

Space nuclear power and nuclear electric propulsion are considered important technologies for planetary exploration, as well as selected earth orbit applications. The Nuclear Electric Propulsion Space Test Program (NEPSTP) was intended to provide an early flight demonstration of these technologies at relatively low cost through extensive use of existing Russian technology. The key element of Russian technology employed in the program was the Topaz II reactor. Refocusing of the activities of the Ballistic Missile Defense Organization (BMDO), combined with budgetary pressures, forced the cancellation of the NEPSTP at the end of the 1993 fiscal year. The NEPSTP was faced with many unique flight qualification issues. In general, the launch of a spacecraft employing a nuclear reactor power system complicates many spacecraft qualification activities. However, the NEPSTP activities were further complicated because the reactor power system was a Russian design. Therefore, this program considered not only the unique flight qualification issues associated with space nuclear power, but also with differences between Russian and United States flight qualification procedures. This paper presents an overview of the NEPSTP. The program goals, the proposed mission, the spacecraft, and the Topaz II space nuclear power system are described. The subject of flight qualification is examined and the inherent difficulties of qualifying a space reactor are described. The differences between United States and Russian flight qualification procedures are explored. A plan is then described that was developed to determine an appropriate flight qualification program for the Topaz II reactor to support a possible NEPSTP launch

LIE n-RACKS

OpenAIRE

Biyogmam, Guy Roger

2011-01-01

In this paper, we introduce the category of Lie $n$-racks and generalize several results known on racks. In particular, we show that the tangent space of a Lie $n$-Rack at the neutral element has a Leibniz $n$-algebra structure. We also define a cohomology theory of $n$-racks..

Description of nuclear properties

International Nuclear Information System (INIS)

Faessler, A.

1991-01-01

The lectures want to give a survey about new developments in the description of nuclei. In a first chapter we try to derive nuclear properties from the basis theory of quantum chromodynamics. This is not rigorously possible. There are still many cracks in the bridge between QCD and nuclear structure. The basic ingredient for nuclear structure calculations is the nucleon-nucleon interaction. We shall discuss the nucleon-nucleon interaction in a quark model. In a further chapter we discuss the way to come from a bare nucleon-nucleon interaction in free space to an effective nucleon-nucleon interaction in a limited model space for nuclear structure calculations. Such nuclear structure calculations can be done as shell model calculations. But they are due to the large number of configurations limited to light nuclei. We discuss possibilities (MONSTER and VAMPIR) to enlarge the model space for medium heavy and heavy nuclei. As the example of the low lying isovector 1 + states we discuss collective models (Bohr - Mottelson Model, interacting Boson Model) with proton and neutron degrees of freedom. The same states can also be described microscopically with the Quasi-Particle Random Phase Approximation (QRPA). We discuss the removal of spurious states in RPA. We also discuss the calculation of form factors and compare with inelastic electron scattering data. Finally we apply QRPA to the double-beta decay. Grand unified models predict, that the neutrino is identical with his antiparticle, that it has a finite mass and a weak right-handed interaction. If these properties are found the standard model of the strong and the electro-weak interaction can not be correct. Presently we can only derive from lower limits of the half lives of neutrinoless double-beta decays upper limits of the neutrino mass and of the right-handedness of the weak interaction and lower limits of the mass of the right handed heavy vector boson, if a specific grand unified model is given. (author)

Uncovering Special Nuclear Materials by Low-energy Nuclear Reaction Imaging.

Science.gov (United States)

Rose, P B; Erickson, A S; Mayer, M; Nattress, J; Jovanovic, I

2016-04-18

Weapons-grade uranium and plutonium could be used as nuclear explosives with extreme destructive potential. The problem of their detection, especially in standard cargo containers during transit, has been described as "searching for a needle in a haystack" because of the inherently low rate of spontaneous emission of characteristic penetrating radiation and the ease of its shielding. Currently, the only practical approach for uncovering well-shielded special nuclear materials is by use of active interrogation using an external radiation source. However, the similarity of these materials to shielding and the required radiation doses that may exceed regulatory limits prevent this method from being widely used in practice. We introduce a low-dose active detection technique, referred to as low-energy nuclear reaction imaging, which exploits the physics of interactions of multi-MeV monoenergetic photons and neutrons to simultaneously measure the material's areal density and effective atomic number, while confirming the presence of fissionable materials by observing the beta-delayed neutron emission. For the first time, we demonstrate identification and imaging of uranium with this novel technique using a simple yet robust source, setting the stage for its wide adoption in security applications.

The nuclear isomer transition in Thorium-229. Search for the VUV photon

Energy Technology Data Exchange (ETDEWEB)

Stellmer, Simon [TU Wien (Austria). Atominstitut; VCQ, Vienna (Austria); Schreitl, Matthias; Schumm, Thorsten [TU Wien (Austria). Atominstitut; Yoshimura, Koji [Okayama University (Japan)

2015-07-01

The isotope {sup 229}Th is believed to possess a low-lying nuclear excitation, at an energy of about 7.8(5) eV, corresponding to a wavelength of 160(10) nm. Convincing direct evidence of the existence of this state, for instance by observation of its excitation or decay, is still pending. Optical excitation of the isomer state is an exceptional challenge, as the required wavelength is not known, the transition is believed to be extremely narrow, and the choice of suitable lasers is limited. Instead, we use synchrotron radiation at 29 keV to populate the second excited state, which then decays into the desired isomer state. This state proceeds further into the ground state under emission of the much sought-after VUV photon. This photon is detected in a spectrometer. The measurements are performed at the SPring-8 facility in Japan; we will report on the latest status of the experiment.

From simplicial Lie algebras and hypercrossed complexes to differential graded Lie algebras via 1-jets

OpenAIRE

Jurco, Branislav

2011-01-01

Let g be a simplicial Lie algebra with Moore complex Ng of length k. Let G be the simplicial Lie group integrating g, which is simply connected in each simplicial level. We use the 1-jet of the classifying space of G to construct, starting from g, a Lie k-algebra L. The so constructed Lie k-algebra L is actually a differential graded Lie algebra. The differential and the brackets are explicitly described in terms (of a part) of the corresponding k-hypercrossed complex structure of Ng. The res...

Solid state nuclear track detection principles, methods and applications

CERN Document Server

Durrani, S A; ter Haar, D

1987-01-01

Solid State Nuclear Track Detection: Principles, Methods and Applications is the second book written by the authors after Nuclear Tracks in Solids: Principles and Applications. The book is meant as an introduction to the subject solid state of nuclear track detection. The text covers the interactions of charged particles with matter; the nature of the charged-particle track; the methodology and geometry of track etching; thermal fading of latent damage trails on tracks; the use of dielectric track recorders in particle identification; radiation dossimetry; and solid state nuclear track detecti

Low-mass neutron stars: universal relations, the nuclear symmetry energy and gravitational radiation

Science.gov (United States)

O. Silva, Hector; Berti, Emanuele; Sotani, Hajime

2016-03-01

Compact objects such as neutron stars are ideal astrophysical laboratories to test our understanding of the fundamental interactions in the regime of supranuclear densities, unachievable by terrestrial experiments. Despite recent progress, the description of matter (i.e., the equation of state) at such densities is still debatable. This translates into uncertainties in the bulk properties of neutron stars, masses and radii for instance. Here we will consider low-mass neutron stars. Such stars are expected to carry important information on nuclear matter near the nuclear saturation point. It has recently been shown that the masses and surface redshifts of low-mass neutron stars smoothly depend on simple functions of the central density and of a characteristic parameter η associated with the choice of equation of state. Here we extend these results to slowly-rotating and tidally deformed stars and obtain empirical relations for various quantities, such as the moment of inertia, quadrupole moment and ellipticity, tidal and rotational Love numbers, and rotational apsidal constants. We discuss how these relations might be used to constrain the equation of state by future observations in the electromagnetic and gravitational-wave spectra.

Present state of nuclear power business in China

International Nuclear Information System (INIS)

Morokuzu, Muneo

2011-01-01

This article presented present state of nuclear power business in China based on latest information obtained at visit at nuclear power related facilities in December 2010. China Atomic Energy Authority (CAEA) promoted nuclear power, while National Nuclear Safety Administration (NNSA) was an independent regulatory body of nuclear power. Construction of nuclear power was promoted by three national nuclear engineering development corporations: China National Nuclear Corporation (CNNC), China Guangdon Nuclear Power Corporation (CGNPC) and State Nuclear Power Technology Corporation (SNPTC). In China, 13 nuclear power reactors were in operation and 27 under construction. Shortage of nuclear engineers became evident with rapid growth of nuclear power, which forced delay of nuclear power construction schedule. Future strategies of reactor type varied domestic, French and US ones respectively dependent on CNNC, CGNPC and SNPTC, CNNC seemed to change from third generation reactor (CNP 1000) to second one (CP 1000) due to regulatory licensing difficulty of NNSA. As for advanced reactor development, large scale PWR project, HTR project and FBR development project were proceeding. As HTR project was selected as high-priority project, an experimental reactor (HTR-10) was critical in 2000 and construction of demonstration reactor started in 2009. (T. Tanaka)

Nonflexible Lie-admissible algebras

International Nuclear Information System (INIS)

Myung, H.C.

1978-01-01

We discuss the structure of Lie-admissible algebras which are defined by nonflexible identities. These algebras largely arise from the antiflexible algebras, 2-varieties and associator dependent algebras. The nonflexible Lie-admissible algebras in our discussion are in essence byproducts of the study of nonassociative algebras defined by identities of degree 3. The main purpose is to discuss the classification of simple Lie-admissible algebras of nonflexible type

Low-charge-state linac

Energy Technology Data Exchange (ETDEWEB)

Shepard, K.W.; Kim, J.W.

1995-08-01

A design is being developed for a low-charge-state linac suitable for injecting ATLAS with a low-charge-state, radioactive beam. Initial work indicates that the existing ATLAS interdigital superconducting accelerating structures, together with the superconducting quadrupole transverse focussing element discussed above, provides a basis for a high-performance low-charge-state linac. The initial 2 or 3 MV of such a linac could be based on a normally-conducting, low-frequency RFQ, possibly combined with 24-MHz superconducting interdigital structures. Beam dynamics studies of the whole low-charge-state post-accelerator section were carried out in early FY 1995.

Data on inelastic processes in low-energy potassium-hydrogen and rubidium-hydrogen collisions

Science.gov (United States)

Yakovleva, S. A.; Barklem, P. S.; Belyaev, A. K.

2018-01-01

Two sets of rate coefficients for low-energy inelastic potassium-hydrogen and rubidium-hydrogen collisions were computed for each collisional system based on two model electronic structure calculations, performed by the quantum asymptotic semi-empirical and the quantum asymptotic linear combinations of atomic orbitals (LCAO) approaches, followed by quantum multichannel calculations for the non-adiabatic nuclear dynamics. The rate coefficients for the charge transfer (mutual neutralization, ion-pair formation), excitation and de-excitation processes are calculated for all transitions between the five lowest lying covalent states and the ionic states for each collisional system for the temperature range 1000-10 000 K. The processes involving higher lying states have extremely low rate coefficients and, hence, are neglected. The two model calculations both single out the same partial processes as having large and moderate rate coefficients. The largest rate coefficients correspond to the mutual neutralization processes into the K(5s 2S) and Rb(4d 2D) final states and at temperature 6000 K have values exceeding 3 × 10-8 cm3 s-1 and 4 × 10-8 cm3 s-1, respectively. It is shown that both the semi-empirical and the LCAO approaches perform equally well on average and that both sets of atomic data have roughly the same accuracy. The processes with large and moderate rate coefficients are likely to be important for non-LTE modelling in atmospheres of F, G and K-stars, especially metal-poor stars.

Semiclassical approaches to nuclear dynamics

Energy Technology Data Exchange (ETDEWEB)

Magner, A. G., E-mail: magner@kinr.kiev.ua; Gorpinchenko, D. V. [Institute for Nuclear Research NASU (Ukraine); Bartel, J. [Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien, CNRS/IN2P3 (France)

2017-01-15

The extended Gutzwiller trajectory approach is presented for the semiclassical description of nuclear collective dynamics, in line with the main topics of the fruitful activity of V.G. Solovjov. Within the Fermi-liquid droplet model, the leptodermous effective surface approximation was applied to calculations of energies, sum rules, and transition densities for the neutron–proton asymmetry of the isovector giant-dipole resonance and found to be in good agreement with the experimental data. By using the Strutinsky shell correction method, the semiclassical collective transport coefficients, such as nuclear inertia, friction, stiffness, and moments of inertia, can be derived beyond the quantum perturbation approximation of the response function theory and the cranking model. The averaged particle-number dependences of the low-lying collective vibrational states are described in good agreement with the basic experimental data, mainly due to the enhancement of the collective inertia as compared to its irrotational flow value. Shell components of the moment of inertia are derived in terms of the periodic-orbit free-energy shell corrections. A good agreement between the semiclassical extended Thomas–Fermi moments of inertia with shell corrections and the quantum results is obtained for different nuclear deformations and particle numbers. Shell effects are shown to be exponentially dampted out with increasing temperature in all the transport coefficients.

Semiclassical approaches to nuclear dynamics

International Nuclear Information System (INIS)

Magner, A. G.; Gorpinchenko, D. V.; Bartel, J.

2017-01-01

The extended Gutzwiller trajectory approach is presented for the semiclassical description of nuclear collective dynamics, in line with the main topics of the fruitful activity of V.G. Solovjov. Within the Fermi-liquid droplet model, the leptodermous effective surface approximation was applied to calculations of energies, sum rules, and transition densities for the neutron–proton asymmetry of the isovector giant-dipole resonance and found to be in good agreement with the experimental data. By using the Strutinsky shell correction method, the semiclassical collective transport coefficients, such as nuclear inertia, friction, stiffness, and moments of inertia, can be derived beyond the quantum perturbation approximation of the response function theory and the cranking model. The averaged particle-number dependences of the low-lying collective vibrational states are described in good agreement with the basic experimental data, mainly due to the enhancement of the collective inertia as compared to its irrotational flow value. Shell components of the moment of inertia are derived in terms of the periodic-orbit free-energy shell corrections. A good agreement between the semiclassical extended Thomas–Fermi moments of inertia with shell corrections and the quantum results is obtained for different nuclear deformations and particle numbers. Shell effects are shown to be exponentially dampted out with increasing temperature in all the transport coefficients.

Doorway states in nuclear reactions as a manifestation of the 'super-radiant' mechanism

International Nuclear Information System (INIS)

Auerbach, N.; Zelevinsky, V.

2007-01-01

A mechanism is considered for generating doorway states and intermediate structure in low-energy nuclear reactions as a result of collectivization of widths of unstable intrinsic states coupled to common decay channels. At the limit of strong continuum coupling, the segregation of broad ('super-radiating') and narrow ('trapped') states occurs revealing the separation of direct and compound processes. We discuss the conditions for the appearance of intermediate structure in this process and doorways related to certain decay channels

Pion production and the nuclear equation of state

International Nuclear Information System (INIS)

Harris, J.W.; Odyniec, G.; Pugh, H.G.

1984-10-01

There has been considerable recent interest in the nuclear equation of state and how it may be determined in relativistic nucleus-nucleus collisions. In these collisions extremely high temperatures are reached and compression to densities several times that of normal nuclear matter are predicted. This affords us the unique opportunity to study, in a somewhat controlled manner, the behavior of nuclear matter under these extreme conditions. If the observables that are measured in experiments can be related in a quantitative way to state variables of the system then the equation of state can be extracted. This relation plays a very important role in understanding the formation and collapse of supernovae and the stability and structure of neutron stars. Furthermore, it can be used to test and constrain field theoretical approaches to nuclear matter and to help to better understand the dynamics of high energy nucleus-nucleus collisions. In this presentation the relationship between the nuclear equation of state and relativistic nucleus-nucleus collisions will be discussed with an emphasis on how to extract the former. That a high density state of the collision should exist will be shown. One observable, namely the pion multiplicity, will be shown to survive the succeeding stages of the collision process to provide information on the equation of state at high densities. The resulting equation of state will be presented and discussed in the light of recent theoretical development. 34 refs., 12 figs

Isomorphism of Intransitive Linear Lie Equations

Directory of Open Access Journals (Sweden)

Jose Miguel Martins Veloso

2009-11-01

Full Text Available We show that formal isomorphism of intransitive linear Lie equations along transversal to the orbits can be extended to neighborhoods of these transversal. In analytic cases, the word formal is dropped from theorems. Also, we associate an intransitive Lie algebra with each intransitive linear Lie equation, and from the intransitive Lie algebra we recover the linear Lie equation, unless of formal isomorphism. The intransitive Lie algebra gives the structure functions introduced by É. Cartan.

Filiform Lie algebras of order 3

Science.gov (United States)

Navarro, R. M.

2014-04-01

The aim of this work is to generalize a very important type of Lie algebras and superalgebras, i.e., filiform Lie (super)algebras, into the theory of Lie algebras of order F. Thus, the concept of filiform Lie algebras of order F is obtained. In particular, for F = 3 it has been proved that by using infinitesimal deformations of the associated model elementary Lie algebra it can be obtained families of filiform elementary lie algebras of order 3, analogously as that occurs into the theory of Lie algebras [M. Vergne, "Cohomologie des algèbres de Lie nilpotentes. Application à l'étude de la variété des algèbres de Lie nilpotentes," Bull. Soc. Math. France 98, 81-116 (1970)]. Also we give the dimension, using an adaptation of the {sl}(2,{C})-module Method, and a basis of such infinitesimal deformations in some generic cases.

When is a lie more of a lie? Moral judgment mediates the relationship between perceived benefits of others and lie-labeling

Directory of Open Access Journals (Sweden)

Cantarero Katarzyna

2017-06-01

Full Text Available Lay perceptions of lying are argued to consist of a lie prototype. The latter was found to entail the intention to deceive, belief in falsity and falsity (Coleman & Kay, 1981. We proposed and found that the perceptions of the benefits of others are also an important factor that influences the extent, to which an act of intentional misleading someone to foster a false belief is labeled as a lie. Drawing from the intuitionist model of moral judgments (Haidt, 2001 we assumed that moral judgment of the behaviour would mediate the relationship. In Study 1 we analyzed data coming from a crosscultural project and found that perceived intention to benefit others was negatively related to lie labeling and that this relationship was mediated by the moral judgment of that act. In Study 2 we found that manipulating the benefits of others influenced the extent, to which an act of intentional misleading in order to foster a false belief is labeled as a lie and that, again, this relationship is mediated by the moral judgment of that act.

Status of nuclear desalination in IAEA member states

International Nuclear Information System (INIS)

2007-01-01

Some of the IAEA Member States have active nuclear desalination programmes and, during the last few years, substantial overall progress has been made in this field. As part of the ongoing activities within the IAEA's nuclear power programme, it was thus decided to prepare a status report, which would briefly describe the recent nuclear seawater desalination related developments and relevant IAEA activities. This status report briefly covers salient aspects of the new generation reactors and a few innovative reactors being considered for desalination and other non-electrical applications, the recent advances in the commonly employed desalination processes and their coupling to nuclear reactors. A summary of techno-economic feasibility studies carried out in interested Member States has been presented and the potable water cost reduction strategies from nuclear desalination plants have been discussed. The socio-economic and environmental benefits of nuclear power driven desalination plants have been elaborated. It is expected that the concise information provided in this report would be useful to the decision makers in the Member States and would incite them to consider or to accelerate the deployment of nuclear desalination projects in their respective countries

Study of ground-state configuration of neutron-rich aluminium isotopes through electromagnetic excitation

International Nuclear Information System (INIS)

Chakraborty, S.; Datta Pramanik, U.; Chatterjee, S.

2013-01-01

The region of the nuclear chart around neutron magic number, N∼20 and proton number (Z), 10≤ Z≤12 is known as the Island of Inversion. The valance neutron(s) of these nuclei, even in their ground state, are most likely occupying the upper pf orbitals which are normally lying above sd orbitals, N∼20 shell closure. Nuclei like 34,35 Al are lying at the boundary of this Island of Inversion. Little experimental information about their ground state configuration are available in literature

Lie Algebras and Integrable Systems

International Nuclear Information System (INIS)

Zhang Yufeng; Mei Jianqin

2012-01-01

A 3 × 3 matrix Lie algebra is first introduced, its subalgebras and the generated Lie algebras are obtained, respectively. Applications of a few Lie subalgebras give rise to two integrable nonlinear hierarchies of evolution equations from their reductions we obtain the nonlinear Schrödinger equations, the mKdV equations, the Broer-Kaup (BK) equation and its generalized equation, etc. The linear and nonlinear integrable couplings of one integrable hierarchy presented in the paper are worked out by casting a 3 × 3 Lie subalgebra into a 2 × 2 matrix Lie algebra. Finally, we discuss the elliptic variable solutions of a generalized BK equation. (general)

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)

Results of activities of the State Office for Nuclear Safety in state supervision of nuclear safety of nuclear facilities and radiation protection in 2003

International Nuclear Information System (INIS)

Kovar, P.

2004-01-01

The report summarises results of activities of the State Office for Nuclear Safety (SUJB) in the supervision of nuclear safety and radiation protection in the Czech Republic. The first part of the report evaluates nuclear safety of nuclear installations and contains information concerning the results of supervision of radiation protection in 2003 in the Czech Republic. The second part of the report describes new responsibilities of the SUJB in the domain of nuclear, chemical, bacteriological (biological) and toxin weapons ban. (author)

Low cost nuclear data printer

International Nuclear Information System (INIS)

Punnachiya, S.; Aungkultewaraksa, S.; Pengphol, S.

1988-01-01

The data printer is essential for nuclear radiation measuring system. A low cost nuclear data printer is developed from an electronic printing calculator. It can transfer the counting data from scaler and printout. The basic concept is that the BCD data is transferred and converted to decimal data sequentially by the interfacing circuit. After the counting time is ended, each digit is transferred to the printing calculator by data bus, digit by digit, until all the data are transferred and printed out. The low cost nuclear data printer consists of a CASIO model HR-8 electronic printing calculator and a printer interface model either NT 2602 or NT 2603 which are designed for printing out 6 digit data from the counter/timer CANBERRA model 1772. In this research the NT 2602 interface is designed only to transfer and printing out data. While the NT 2603 interface is designed to transfer, print out and average data. The NT 2603 can average from 2 to 9 sets of counting data. This data interfacing technique can be applied to work with all scientific instruments having readout as digital display and all kinds of electronic printing calculator

Collective and single-particle states at high excitation energy

International Nuclear Information System (INIS)

Van den Berg, A.M.; Van der Molen, H.K.T.; Harakeh, M.N.; Akimune, H.; Daito, I.; Fujimura, H.; Fujiwara, M.; Ihara, F.; Inomata, T.

2000-01-01

Complete text of publication follows. Damping of high-lying single-particle states was investigated by the study of proton decay from high-lying states in 91 Nb, populated by the 90 Zr(α,t) reaction with E α = 180 MeV. In addition to decay to the ground state of 90 Zr, semi-direct decay was observed to the low-lying (2 + and 3 - ) phonon states, confirming the conclusion from other experiments that these phonon states play an important role in the damping process of the single-particle states. Furthermore, the population and decay of Isobaric Analogue States of 91 Zr, which are located at an excitation energy of about 10 - 12 MeV in 91 Nb, has been studied in the same reaction. (author)

Filiform Lie algebras of order 3

International Nuclear Information System (INIS)

Navarro, R. M.

2014-01-01

The aim of this work is to generalize a very important type of Lie algebras and superalgebras, i.e., filiform Lie (super)algebras, into the theory of Lie algebras of order F. Thus, the concept of filiform Lie algebras of order F is obtained. In particular, for F = 3 it has been proved that by using infinitesimal deformations of the associated model elementary Lie algebra it can be obtained families of filiform elementary lie algebras of order 3, analogously as that occurs into the theory of Lie algebras [M. Vergne, “Cohomologie des algèbres de Lie nilpotentes. Application à l’étude de la variété des algèbres de Lie nilpotentes,” Bull. Soc. Math. France 98, 81–116 (1970)]. Also we give the dimension, using an adaptation of the sl(2,C)-module Method, and a basis of such infinitesimal deformations in some generic cases

1984 state-by-state assessment of low-level radioactive wastes shipped to commercial disposal sites

International Nuclear Information System (INIS)

1985-12-01

The 1984 report uses the volume of low-level waste reported as received at each commercial disposal site as the national baseline figure. A volume of 75,429 m 3 of radioactive waste containing 600,909 Ci of activity was reported disposed at the commercial sites in 1984. The distribution of these waste volumes by disposal site is presented in Table 1. Table 2 displays typical radionuclides in low-level wastes by sector. Table 3 presents predominant waste forms associated with low-level waste by sector. The total volume and curie values tabulated for each state were obtained directly from the commercial disposal site operators. The total is the sum of the volume and radioactivity reported by Chem Nuclear and US Ecology for each state. Figure 1 displays the disposal capacity remaining at Barnwell, Richland, and Beatty commercial disposal sites as of December 31, 1984. Summary information on commercial nuclear power plant wastes was obtained from semiannual waste and effluent reports submitted to the NRC in accordance with the NRC Regulatory Guide 1.21. Where reported data were not available, data were obtained by communication with the utility. Non-reactor waste volumes are actual amounts recorded as received at the commercial waste repositories in 1984. Waste categories are defined as academic, medical, government, and industrial. Academic includes university hospitals and medical and nonmedical research facilities. The medical category includes hospitals and clinics, research facilities, and private medical offices. The industrial category includes private entities such as research and development companies, manufacturers, nondestructive testing, mining, and radiopharmaceutical manufacturers. Government includes state and federal agencies. Data from previous publications were also used as a comparison. 11 refs., 1 fig., 3 tabs

State and nuclear power: conflict and control in the western world

International Nuclear Information System (INIS)

Camilleri, J.A.

1984-01-01

An analysis of the political, cultural, and international dimensions of the nuclear power conflict, this book focuses on the role of the advanced capitalist state in the establishment and subsequent development of the nuclear industry. The author examines the mode, extent, and efficacy of state intervention in nuclear decision making and the political contest which has emerged between pro- and anti-nuclear elements in society, which have confronted the state with a new challenge to its authority. Separate chapter headings are: (1) Origins of the Peaceful Atom, (2) The Emerging Nuclear State, (3) The State's Authority under Challenge, (4) The State and the Crisis of Legitimacy, (5) The Impact of Recession, (6) The Politics of the Fuel Cycle, (7) International Nuclear Politics, and (8) Nuclear Power and the Crisis of Capitalism. 47 references, 1 figure, 3 tables

Identification of the one-quadrupole phonon 21,ms+ state of 204Hg

Directory of Open Access Journals (Sweden)

R. Stegmann

2017-07-01

Full Text Available One-phonon states of vibrational nuclei with mixed proton–neutron symmetry have been observed throughout the nuclear chart besides the mass A≈200 region. Very recently, it has been proposed that the 22+ state of 212Po is of isovector nature. This nucleus has two valence protons and two valence neutrons outside the doubly-magic 208Pb nucleus. The stable isotope 204Hg, featuring two valence-proton and valence-neutron holes, with respect to 208Pb, is the particle-hole mirror of 212Po. In order to compare the properties of low-lying isovector excitations in these particle-hole mirror nuclei, we have studied 204Hg by using the projectile Coulomb-excitation technique. The measured absolute B(M1;22+→21+ strength of 0.20(2μN2 indicates that the 22+ level of 204Hg is at least the main fragment of the 21,ms+ state. For the first time in this mass region, both lowest-lying, one-quadrupole phonon excitations are established together with the complete set of their decay strengths. This allows for a microscopic description of their structures, achieved in the framework of the Quasi-particle Phonon Model.

Non-nuclear, low-carbon, or both? The case of Taiwan

International Nuclear Information System (INIS)

Chen, Yen-Heng Henry

2013-01-01

The Fukushima nuclear accident in Japan has renewed debates on the safety of nuclear power, possibly hurting the role of nuclear power in efforts to limit CO 2 emissions. I develop a dynamic economy-wide model of Taiwan with a detailed set of technology options in the power sector to examine the implications of adopting different carbon and nuclear power policies on CO 2 emissions and the economy. Without a carbon mitigation policy, limiting nuclear power has a small economic cost for Taiwan, but CO 2 emissions may increase by around 4.5% by 2050 when nuclear is replaced by fossil-based generation. With a low-carbon target of a 50% reduction from year 2000 levels by 2050, the costs of cutting CO 2 emissions are greatly reduced if both carbon sequestration and nuclear expansion were viable. This study finds that converting Taiwan's industrial structure into a less energy-intensive one is crucial to carry out the non-nuclear and low-carbon environment. - Highlights: • This study provides an analysis for Taiwan under a low-carbon policy with or without the nuclear option. • A new approach that improves the modeling of non-dispatchable generation is presented. • Emission reduction costs are greatly reduced if both carbon sequestration and nuclear expansion were viable. • A less energy-intensive industrial structure is crucial in pursuing a non-nuclear and low carbon environment

Nuclear scissors modes and hidden angular momenta

Energy Technology Data Exchange (ETDEWEB)

Balbutsev, E. B., E-mail: balbuts@theor.jinr.ru; Molodtsova, I. V. [Joint Institute for Nuclear Research (Russian Federation); Schuck, P. [Université Paris-Sud, Institut de Physique Nucléaire, IN2P3–CNRS (France)

2017-01-15

The coupled dynamics of low-lying modes and various giant resonances are studied with the help of the Wigner Function Moments method generalized to take into account spin degrees of freedom and pair correlations simultaneously. The method is based on Time-Dependent Hartree–Fock–Bogoliubov equations. The model of the harmonic oscillator including spin–orbit potential plus quadrupole–quadrupole and spin–spin interactions is considered. New low-lying spin-dependent modes are analyzed. Special attention is paid to the scissors modes. A new source of nuclear magnetism, connected with counter-rotation of spins up and down around the symmetry axis (hidden angular momenta), is discovered. Its inclusion into the theory allows one to improve substantially the agreement with experimental data in the description of energies and transition probabilities of scissors modes.

Development of advanced low alloy steel for nuclear RPV

Energy Technology Data Exchange (ETDEWEB)

Lee, H. C.; Shin, K. S.; Lee, S. H.; Lee, B. J. [Seoul National Univ., Seoul (Korea)

2000-04-01

Low carbon low alloy steels are used in nuclear power plants as pressure vessel, steam generator, etc. Nuclear pressure vessel material requires good combination of strength/ toughness, good weldability and high resistance to neutron irradiation and corrosion fatigue. For SA508III steels, most widely used in the production of nuclear power plant, attaining toughness is more difficult than strength. When taking into account the loss of toughness due to neutron irradiation, attaining as low transition temperature as possible prior to operation is a critical task in the production of nuclear pressure vessels. In the present study, we investigated detrimental microstructural features of SA508III steels to toughness, then alloy design directions to achieve improved mechanical properties were devised. The next step of alloy design was determined based on phase equilibrium thermodynamics and obtained results. Low carbon low alloy steels having low transition temperatures with enough strength and hardenability were developed. Microstructure and mechanical properties of HAZ of SA508III steels and alloy designed steels were investigated. 22 refs., 147 figs., 38 tabs. (Author)

Low-level radioactive waste disposal in the United States

International Nuclear Information System (INIS)

Ozaki, Calvin B.; Kerr, Thomas A.; Williams, R. Eric

1991-01-01

Two national systems comprise the low-level radioactive waste management system in the United States of America. The U.S. Nuclear Regulatory Commission regulates low-level radioactive waste produced in the public sector (commercial waste), and the U.S. Department of Energy manages low-level radioactive waste produced by government-sponsored programs. The primary distinction between the two national systems is the source of regulatory control. This paper discusses two issues critical to the success of each system: the site selection process used by the commercial low-level waste disposal system, and the evaluation process used to determine configuration of the DOE waste management system. The two national systems take different approaches to reach the same goals, which are increased social responsibility, protection of public health and safety, and protection of the environment

Little strings, quasi-topological sigma model on loop group, and toroidal Lie algebras

Directory of Open Access Journals (Sweden)

Meer Ashwinkumar

2018-03-01

Full Text Available We study the ground states and left-excited states of the Ak−1 N=(2,0 little string theory. Via a theorem by Atiyah [1], these sectors can be captured by a supersymmetric nonlinear sigma model on CP1 with target space the based loop group of SU(k. The ground states, described by L2-cohomology classes, form modules over an affine Lie algebra, while the left-excited states, described by chiral differential operators, form modules over a toroidal Lie algebra. We also apply our results to analyze the 1/2 and 1/4 BPS sectors of the M5-brane worldvolume theory.

Little strings, quasi-topological sigma model on loop group, and toroidal Lie algebras

Science.gov (United States)

Ashwinkumar, Meer; Cao, Jingnan; Luo, Yuan; Tan, Meng-Chwan; Zhao, Qin

2018-03-01

We study the ground states and left-excited states of the Ak-1 N = (2 , 0) little string theory. Via a theorem by Atiyah [1], these sectors can be captured by a supersymmetric nonlinear sigma model on CP1 with target space the based loop group of SU (k). The ground states, described by L2-cohomology classes, form modules over an affine Lie algebra, while the left-excited states, described by chiral differential operators, form modules over a toroidal Lie algebra. We also apply our results to analyze the 1/2 and 1/4 BPS sectors of the M5-brane worldvolume theory.

On lying and deceiving.

OpenAIRE

Bakhurst, D

1992-01-01

This article challenges Jennifer Jackson's recent defence of doctors' rights to deceive patients. Jackson maintains there is a general moral difference between lying and intentional deception: while doctors have a prima facie duty not to lie, there is no such obligation to avoid deception. This paper argues 1) that an examination of cases shows that lying and deception are often morally equivalent, and 2) that Jackson's position is premised on a species of moral functionalism that misconstrue...

High-lying neutron hole strengths observed in pick-up reactions

International Nuclear Information System (INIS)

Gales, S.

1980-01-01

Neutron-hole states in orbits well below the Fermi surface have been observed in a number of medium-heavy nuclei from A=90 to 209 using one nucleon pick-up reactions. The excitation energies, angular distributions of such broad and enhanced structures will be discussed. The fragmentation of the neutron-hole strengths as well as the spreading of such simple mode of excitations into more complex states are compared to recent calculations within the quasiparticle-phonon or the single particle-vibration coupling nuclear models. We report on recent measurements of J for inner-hole states in 89 Zr and 115 Sn 119 Sn using the analyzing power of the (p,d) and (d,t) reactions. Large enhancement of cross-sections are observed at high excitation energy in the study of the (p,t) reactions on Zr, Cd, Sn, Te and Sm isotopes. The systematic features of such high-lying excitation are related to the ones observed in one neutron pick-up experiments. The origin of such concentration of two neutron-hole strengths in Cd and Sn isotopes will be discussed. Preliminary results obtained in the study of the (α, 6 He) reaction at 218 MeV incident energy on 90 Zr, 118 Sn and 208 Pb targets are presented and compared to the (p,t) results. Finally the properties of hole-analog states populated in neutron pick-up reactions (from 90 Zr to 208 Pb) will be presented

Nuclear desalination of sea water. Proceedings of an international symposium

International Nuclear Information System (INIS)

1997-01-01

About 250 participants from 24 Member States and seven international organizations took part in the Symposium. A wide variety of topics related to nuclear desalination were reviewed and discussed. These covered the activities of some organizations and institutes, the experience gained in existing nuclear desalination plants and their facilities, national and bilateral programmes, including research, design and development, forecasts for the future and the challenges that lie ahead. It is hoped that the Proceedings will be of value to technical, financial and regulatory decision makers associated with nuclear desalination

Nuclear deterrence in second tier nuclear weapon states: a case study of India

International Nuclear Information System (INIS)

Sethi, Manpreet

2009-12-01

Nuclear deterrence today anchors the national security of all states that possess nuclear weapons. Certain principles or requirements of nuclear deterrence are the same for all such countries. For instance, the ability to threaten with unacceptable damage, or the ability to raise the costs of an action that an adversary might want to take by threatening punishment that would make the act seem meaningless and even regrettable. But must every nuclear nation indulge in an exercise of large-scale warhead accumulation or yield refinements through nuclear testing, or creation of elaborate nuclear war fighting plans in order to claim credible deterrence? Can the practice of deterrence in the second tier states follow a different course? The study examines the manner in which India is engaged in constructing a credible and stable deterrence relationship with two of its nuclear armed adversaries, Pakistan and China with an arsenal much smaller, and command and control structures far simpler than in any of the P-5 nations. Does this difference impact the nature of its nuclear deterrence? In its efforts at creating and sustaining credible nuclear deterrence should India necessarily be expected to follow the same path and rules as those of the P-5? Would it be compelled to build hundreds of warheads and a huge weapons infrastructure? Would a deterrence based on anything less not be credible or stable? The study concludes that even countries with small nuclear arsenals behave no differently from states that possess several thousands of such weapons. The assumption that small nuclear arsenals and rudimentary command and control lend themselves to temptations of easy nuclear use is misplaced. Credible nuclear deterrence between India and Pakistan or India and China would hold on the same bases it has held elsewhere - fear of nuclear destruction, imposition of unacceptable damage, and the ability to rationally calculate and weigh the benefits against the costs of use of nuclear

Theory of super LIE groups

International Nuclear Information System (INIS)

Prakash, M.

1985-01-01

The theory of supergravity has attracted increasing attention in the recent years as a unified theory of elementary particle interactions. The superspace formulation of the theory is highly suggestive of an underlying geometrical structure of superspace. It also incorporates the beautifully geometrical general theory of relativity. It leads us to believe that a better understanding of its geometry would result in a better understanding of the theory itself, and furthermore, that the geometry of superspace would also have physical consequences. As a first step towards that goal, we develop here a theory of super Lie groups. These are groups that have the same relation to a super Lie algebra as Lie groups have to a Lie algebra. More precisely, a super Lie group is a super-manifold and a group such that the group operations are super-analytic. The super Lie algebra of a super Lie group is related to the local properties of the group near the identity. This work develops the algebraic and super-analytical tools necessary for our theory, including proofs of a set of existence and uniqueness theorems for a class of super-differential equations

Computations in finite-dimensional Lie algebras

Directory of Open Access Journals (Sweden)

A. M. Cohen

1997-12-01

Full Text Available This paper describes progress made in context with the construction of a general library of Lie algebra algorithms, called ELIAS (Eindhoven Lie Algebra System, within the computer algebra package GAP. A first sketch of the package can be found in Cohen and de Graaf[1]. Since then, in a collaborative effort with G. Ivanyos, the authors have continued to develop algorithms which were implemented in ELIAS by the second author. These activities are part of a bigger project, called ACELA and financed by STW, the Dutch Technology Foundation, which aims at an interactive book on Lie algebras (cf. Cohen and Meertens [2]. This paper gives a global description of the main ways in which to present Lie algebras on a computer. We focus on the transition from a Lie algebra abstractly given by an array of structure constants to a Lie algebra presented as a subalgebra of the Lie algebra of n×n matrices. We describe an algorithm typical of the structure analysis of a finite-dimensional Lie algebra: finding a Levi subalgebra of a Lie algebra.

E1 and M1 strength functions at low energy

Science.gov (United States)

Schwengner, Ronald; Massarczyk, Ralph; Bemmerer, Daniel; Beyer, Roland; Junghans, Arnd R.; Kögler, Toni; Rusev, Gencho; Tonchev, Anton P.; Tornow, Werner; Wagner, Andreas

2017-09-01

We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

E1 and M1 strength functions at low energy

Directory of Open Access Journals (Sweden)

Schwengner Ronald

2017-01-01

Full Text Available We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

Lying in Business : Insights from Hannah Arendt’s ‘Lying in Politics’

NARCIS (Netherlands)

Eenkhoorn, P.; Graafland, J.J.

2010-01-01

The famous political philosopher Hannah Arendt develops several arguments why truthfulness cannot be counted among the political virtues. This article shows that similar arguments apply to lying in business. Based on Hannah Arendt’s theory, we distinguish five reasons why lying is a structural

Development of low-level radioactive waste disposal capacity in the United States - progress or stalemate?

International Nuclear Information System (INIS)

Devgun, J.S.; Larson, G.S.

1995-01-01

It has been fifteen years since responsibility for the disposal of commercially generated low-level radioactive waste (LLW) was shifted to the states by the United States Congress through the Low-Level Radioactive Waste Policy Act of 1980 (LLRWPA). In December 1985, Congress revisited the issue and enacted the Low-Level Radioactive Waste Policy Amendments Act of 1985 (LLRWPAA). No new disposal sites have opened yet, however, and it is now evident that disposal facility development is more complex, time-consuming, and controversial than originally anticipated. For a nation with a large nuclear power industry, the lack of availability of LLW disposal capacity coupled with a similar lack of high-level radioactive waste disposal capacity could adversely affect the future viability of the nuclear energy option. The U.S. nuclear power industry, with 109 operating reactors, generates about half of the LLW shipped to commercial disposal sites and faces dwindling access to waste disposal sites and escalating waste management costs. The other producers of LLW - industries, government (except the defense related research and production waste), academic institutions, and medical institutions that account for the remaining half of the commercial LLW - face the same storage and cost uncertainties. This paper will summarize the current status of U.S. low-level radioactive waste generation and the status of new disposal facility development efforts by the states. The paper will also examine the factors that have contributed to delays, the most frequently suggested alternatives, and the likelihood of change

Development of low-level radioactive waste disposal capacity in the United States -- Progress or stalemate?

International Nuclear Information System (INIS)

Devgun, J.S.

1995-01-01

It has been fifteen years since responsibility for the disposal of commercially generated low-level radioactive waste (LLW) was shifted to the states by the United States Congress through the Low-Level Radioactive Waste Policy Act of 1980 (LLRWPA). In December 1985, Congress revisited the issue and enacted the Low-Level Radioactive Waste Policy Amendments Act of 1985 (LLRWPAA). No new disposal sites have opened yet, however, and it is now evident that disposal facility development is more complex, time-consuming, and controversial than originally anticipated. For a nation with a large nuclear power industry, the lack of availability of LLW disposal capacity coupled with a similar lack of high-level radioactive waste disposal capacity could adversely affect the future viability of the nuclear energy option. The US nuclear power industry, with 109 operating reactors, generates about half of the LLW shipped to commercial disposal sites and faces dwindling access to waste disposal sites and escalating waste management costs. The other producers of LLW -- industries, government (except the defense related research and production waste), academic institutions, and medical institutions that account for the remaining half of the commercial LLW -- face the same storage and cost uncertainties. This paper will summarize the current status of US low-level radioactive waste generation and the status of new disposal facility development efforts by the states. The paper will also examine the factors that have contributed to delays, the most frequently suggested alternatives, and the likelihood of change

The BRST complex and the cohomology of compact lie algebras

International Nuclear Information System (INIS)

Holten, J.W. van

1990-02-01

The authors construct the BRST and anti-BRST operator for a compact Lie algebra which is a direct sum of abelian and simple ideals. Two different inner products are defined on the ghost space and the hermiticity propeties of the ghost and BRST operators with respect to these inner products are discussed. A decomposition theorem for ghost states is derived and the cohomology of the BRST complex is shown to reduce to the standard Lie-algebra cohomology. The authors show that the cohomology classes of the Lie algebra are given by all invariant anti-symmetric tensors and explain how thse can be obtained as zero-modes of an invariant operator in the representation space of the ghosts. Explicit examples are given. (author) 24 refs

Effects of ground state correlations on the structure of odd-mass spherical nuclei

International Nuclear Information System (INIS)

Mishev, S.; Voronov, V. V.

2008-01-01

It is well known that the Pauli principle plays a substantial role at low energies because the quasiparticle and phonon operators, used to describe them, are built of fermions and as a consequence they are not ideal bosons. The correct treatment of this problem requires calculation of the exact commutators between the quasiparticle and phonon operators and in this way to take into account the Pauli principle corrections. In addition to the correlations due to the quasiparticle interaction in the ground-state influence the single-particle fragmentation as well. In this article, we generalize the basic equations of the quasiparticle-phonon nuclear model to account for both effects mentioned above. As an illustration of our approach, calculations of the structure of the low-lying states in the odd-mass nuclei 131-137 Ba have been performed

Lying relies on the truth

NARCIS (Netherlands)

Debey, E.; De Houwer, J.; Verschuere, B.

2014-01-01

Cognitive models of deception focus on the conflict-inducing nature of the truth activation during lying. Here we tested the counterintuitive hypothesis that the truth can also serve a functional role in the act of lying. More specifically, we examined whether the construction of a lie can involve a

Nuclear energy policy in the United States 1990–2010: A federal or state responsibility?

International Nuclear Information System (INIS)

Heffron, Raphael J.

2013-01-01

This paper examines from a policy perspective nuclear energy policy in the United States (US) from 1990 to 2010 and questions whether it is or has become a Federal or State responsibility. The present study, as befits policy research, engages with many disciplines (for example, in particular, law and politics) and hence the contributions move beyond that of nuclear energy policy literature and in particular to that on nuclear new build and other assessments of large infrastructure projects. Several examples at the Federal level are identified that demonstrate that the nuclear industry has evolved to a stage where it requires a focus on the power of actions at a more localised (state) level in order to re-ignite the industry. The research concludes that there remains a misunderstanding of the issue of project management for complex construction projects, and it is highly arguable whether many of its issues have been resolved. Further, the research asserts that the economics of nuclear energy are not the most influential reason for no nuclear new build in the US. -- Highlights: •Examines the US nuclear energy sector, 1990–2010. •Nuclear industry has evolved to a stage where an individual state is the key driver. •Misunderstanding of the project management and public administration. •Potential of the power of more localised (state) actions to re-ignite the industry

Influence of the nuclear matter equation of state on the r-mode instability using the finite-range simple effective interaction

Science.gov (United States)

Pattnaik, S. P.; Routray, T. R.; Viñas, X.; Basu, D. N.; Centelles, M.; Madhuri, K.; Behera, B.

2018-05-01

The characteristic physical properties of rotating neutron stars under the r-mode oscillation are evaluated using the finite-range simple effective interaction. Emphasis is given on examining the influence of the stiffness of both the symmetric and asymmetric parts of the nuclear equation of state on these properties. The amplitude of the r-mode at saturation is calculated using the data of particular neutron stars from the considerations of ‘spin equilibrium’ and ‘thermal equilibrium’. The upper limit of the r-mode saturation amplitude is found to lie in the range 10‑8–10‑6, in agreement with the predictions of earlier work.

Lie families: theory and applications

International Nuclear Information System (INIS)

Carinena, Jose F; Grabowski, Janusz; De Lucas, Javier

2010-01-01

We analyze the families of non-autonomous systems of first-order ordinary differential equations admitting a common time-dependent superposition rule, i.e. a time-dependent map expressing any solution of each of these systems in terms of a generic set of particular solutions of the system and some constants. We next study the relations of these families, called Lie families, with the theory of Lie and quasi-Lie systems and apply our theory to provide common time-dependent superposition rules for certain Lie families.

Nuclear Security Education Program at the Pennsylvania State University

International Nuclear Information System (INIS)

Uenlue, Kenan; Jovanovic, Igor

2015-01-01

The availability of trained and qualified nuclear and radiation security experts worldwide has decreased as those with hands-on experience have retired while the demand for these experts and skills have increased. The U.S. Department of Energy's National Nuclear Security Administration's (NNSA) Global Threat Reduction Initiative (GTRI) has responded to the continued loss of technical and policy expertise amongst personnel and students in the security field by initiating the establishment of a Nuclear Security Education Initiative, in partnership with Pennsylvania State University (PSU), Texas A and M (TAMU), and Massachusetts Institute of Technology (MIT). This collaborative, multi-year initiative forms the basis of specific education programs designed to educate the next generation of personnel who plan on careers in the nonproliferation and security fields with both domestic and international focus. The three universities worked collaboratively to develop five core courses consistent with the GTRI mission, policies, and practices. These courses are the following: Global Nuclear Security Policies, Detectors and Source Technologies, Applications of Detectors/Sensors/Sources for Radiation Detection and Measurements Nuclear Security Laboratory, Threat Analysis and Assessment, and Design and Analysis of Security Systems for Nuclear and Radiological Facilities. The Pennsylvania State University (PSU) Nuclear Engineering Program is a leader in undergraduate and graduate-level nuclear engineering education in the USA. The PSU offers undergraduate and graduate programs in nuclear engineering. The PSU undergraduate program in nuclear engineering is the largest nuclear engineering programs in the USA. The PSU Radiation Science and Engineering Center (RSEC) facilities are being used for most of the nuclear security education program activities. Laboratory space and equipment was made available for this purpose. The RSEC facilities include the Penn State Breazeale

Nuclear Security Education Program at the Pennsylvania State University

Energy Technology Data Exchange (ETDEWEB)

Uenlue, Kenan [The Pennsylvania State University, Radiation Science and Engineering Center, University Park, PA 16802-2304 (United States); The Pennsylvania State University, Department of Mechanical and Nuclear Engineering, University Park, PA 16802-2304 (United States); Jovanovic, Igor [The Pennsylvania State University, Department of Mechanical and Nuclear Engineering, University Park, PA 16802-2304 (United States)

2015-07-01

The availability of trained and qualified nuclear and radiation security experts worldwide has decreased as those with hands-on experience have retired while the demand for these experts and skills have increased. The U.S. Department of Energy's National Nuclear Security Administration's (NNSA) Global Threat Reduction Initiative (GTRI) has responded to the continued loss of technical and policy expertise amongst personnel and students in the security field by initiating the establishment of a Nuclear Security Education Initiative, in partnership with Pennsylvania State University (PSU), Texas A and M (TAMU), and Massachusetts Institute of Technology (MIT). This collaborative, multi-year initiative forms the basis of specific education programs designed to educate the next generation of personnel who plan on careers in the nonproliferation and security fields with both domestic and international focus. The three universities worked collaboratively to develop five core courses consistent with the GTRI mission, policies, and practices. These courses are the following: Global Nuclear Security Policies, Detectors and Source Technologies, Applications of Detectors/Sensors/Sources for Radiation Detection and Measurements Nuclear Security Laboratory, Threat Analysis and Assessment, and Design and Analysis of Security Systems for Nuclear and Radiological Facilities. The Pennsylvania State University (PSU) Nuclear Engineering Program is a leader in undergraduate and graduate-level nuclear engineering education in the USA. The PSU offers undergraduate and graduate programs in nuclear engineering. The PSU undergraduate program in nuclear engineering is the largest nuclear engineering programs in the USA. The PSU Radiation Science and Engineering Center (RSEC) facilities are being used for most of the nuclear security education program activities. Laboratory space and equipment was made available for this purpose. The RSEC facilities include the Penn State Breazeale

Modulation Algorithms for Manipulating Nuclear Spin States

OpenAIRE

Liu, Boyang; Zhang, Ming; Dai, Hong-Yi

2013-01-01

We exploit the impact of exact frequency modulation on transition time of steering nuclear spin states from theoretical point of view. 1-stage and 2-stage Frequency-Amplitude-Phase modulation (FAPM) algorithms are proposed in contrast with 1-stage and 3-stage Amplitude-Phase modulation (APM) algorithms. The sufficient conditions are further present for transiting nuclear spin states within the specified time by these four modulation algorithms. It is demonstrated that transition time performa...

The structure of complex Lie groups

CERN Document Server

Lee, Dong Hoon

2001-01-01

Complex Lie groups have often been used as auxiliaries in the study of real Lie groups in areas such as differential geometry and representation theory. To date, however, no book has fully explored and developed their structural aspects.The Structure of Complex Lie Groups addresses this need. Self-contained, it begins with general concepts introduced via an almost complex structure on a real Lie group. It then moves to the theory of representative functions of Lie groups- used as a primary tool in subsequent chapters-and discusses the extension problem of representations that is essential for studying the structure of complex Lie groups. This is followed by a discourse on complex analytic groups that carry the structure of affine algebraic groups compatible with their analytic group structure. The author then uses the results of his earlier discussions to determine the observability of subgroups of complex Lie groups.The differences between complex algebraic groups and complex Lie groups are sometimes subtle ...

The State Surveillance over Nuclear Safety of Nuclear Facilities Act No. 28/1984

International Nuclear Information System (INIS)

1995-01-01

The Act lays down responsibilities of the Czechoslovak Atomic Energy Commission in the field of state surveillance over nuclear safety of nuclear facilities; determines the responsibilities of nuclear safety inspectors in their inspection activities; specifies duties of bodies and corporations responsible for nuclear safety of nuclear facilities; stipulates the obligation to set up emergency plans; and specifies penalties imposed on corporations and individuals for noncompliance with nuclear safety provisions. The Act entered into force on 4 April 1984. (J.B.)

Evolution of nuclear structure in neutron-rich odd-Zn isotopes and isomers

Directory of Open Access Journals (Sweden)

C. Wraith

2017-08-01

Full Text Available Collinear laser spectroscopy was performed on Zn (Z=30 isotopes at ISOLDE, CERN. The study of hyperfine spectra of nuclei across the Zn isotopic chain, N=33–49, allowed the measurement of nuclear spins for the ground and isomeric states in odd-A neutron-rich nuclei up to N=50. Exactly one long-lived (>10 ms isomeric state has been established in each 69–79Zn isotope. The nuclear magnetic dipole moments and spectroscopic quadrupole moments are well reproduced by large-scale shell–model calculations in the f5pg9 and fpg9d5 model spaces, thus establishing the dominant term in their wave function. The magnetic moment of the intruder Iπ=1/2+ isomer in 79Zn is reproduced only if the νs1/2 orbital is added to the valence space, as realized in the recently developed PFSDG-U interaction. The spin and moments of the low-lying isomeric state in 73Zn suggest a strong onset of deformation at N=43, while the progression towards 79Zn points to the stability of the Z=28 and N=50 shell gaps, supporting the magicity of 78Ni.

Laser photoelectron spectroscopy of MnH - and FeH - : Electronic structures of the metal hydrides, identification of a low-spin excited state of MnH, and evidence for a low-spin ground state of FeH

Science.gov (United States)

Stevens, Amy E.; Feigerle, C. S.; Lineberger, W. C.

1983-05-01

The laser photoelectron spectra of MnH- and MnD-, and FeH- and FeD- are reported. A qualitative description of the electronic structure of the low-spin and high-spin states of the metal hydrides is developed, and used to interpret the spectra. A diagonal transition in the photodetachment to the known high-spin, 7Σ+, ground state of MnH is observed. An intense off-diagonal transition to a state of MnH, at 1725±50 cm-1 excitation energy, is attributed to loss of an antibonding electron from MnH-, to yield a low-spin quintet state of MnH. For FeH- the photodetachment to the ground state is an off-diagonal transition, attributed to loss of the antibonding electron from FeH-, to yield a low-spin quartet ground state of FeH. A diagonal transition results in an FeH state at 1945±55 cm-1; this state of FeH is assigned as the lowest-lying high-spin sextet state of FeH. An additional excited state of MnH and two other excited states of FeH are observed. Excitation energies for all the states are reported; vibrational frequencies and bond lengths for the ions and several states of the neutrals are also determined from the spectra. The electron affinity of MnH is found to be 0.869±0.010 eV; and the electron affinity of FeH is determined to be 0.934±0.011 eV. Spectroscopic constants for the various deuterides are also reported.