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Studies Relating to the Structure of Aluminum Hydride

Description: The object of the work was to determine the molecular structure of AlH/ sub 3/, using the techniques of nuclear spin resonance.'' Attempts to prepare ether-free AlH/sub 3/ that were unsuccessful are described. Also it was not possible to observe the deuterium signal in AlH/sub 3/. It was possible, by the use of the proton signal of the ether in AlH/sub 3/, to obtain the nuclear spin resonance absorption curve for AlH/sub 3/ by subtracting out the contributions of the ether protons to the resona… more
Date: December 16, 1957
Creator: Nickerson, R. F.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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{sup 7}Be(p, {gamma}){sup 8}B and the high-energy solar neutrino flux

Description: Despite thirty years of extensive experimental and theoretical work, the predicted solar neutrino flux is still in sharp disagreement with measurements. The solar neutrino measurements strongly suggest that the problem cannot be solved within the standard electroweak and astrophysical theories. Thus, the solar neutrino problem constitutes the strongest evidence for physics beyond the Standard Model. Whatever the solution of the solar neutrino problem turns out to be, it is of paramount importan… more
Date: August 1, 1997
Creator: Csoto, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An accurate nucleon-nucleon potential with charge-independence breaking

Description: The authors present a new high-quality nucleon-nucleon potential with explicit charge dependence and charge asymmetry, which they designate Argonne {upsilon}{sub 18}. The model has a charge-independent part with fourteen operator components that is an updated version of the Argonne {upsilon}{sub 14} potential. Three additional charge-dependent and one charge-asymmetric operators are added, along with a complete electromagnetic interaction. The potential has been fit directly to the Nijmegen pp … more
Date: August 1, 1994
Creator: Wiringa, R. B.; Stoks, V. G. J. & Schiavilla, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New symmetry regions in the IBA and a simplified approach to nuclear phase transitions

Description: The IBA treatment of nuclear symmetries and transition regions is discussed. A new, extensive region of O(6) nuclei near A = 130 is presented and compared with the Pt isotopes. Nearly identical level schemes characterize both regions, including similar relations between the O(6) and O(5) steps in the dynamical symmetry chain decomposition, and similar discrepancies with the O(6) limit. Simple calculations that incorporate a triaxial component as an O(6) symmetry breaking mechanism remove these … more
Date: January 1, 1984
Creator: Carsten, R. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear non-perturbative excitations

Description: We investigate consequences of a description of nuclear physics in terms of a relativistic field theory. The model Lagrangian contained baryons, sigma-mesons and omega-mesons, and was subsequently extended to include also ..pi..-mesons and rho-mesons. The most important successes of this approach are discussed. In addition to the description of known nuclear structure the field theoretical approach may reveal entirely new nuclear phenomena, based on the explicit treatment of mesonic degrees of … more
Date: January 1, 1984
Creator: Boguta, J. & Kunz, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear dissipation as damping of collective motion in the time-dependent RPA and extensions of it

Description: We have formulated a nonperturbative, microscopic dissipative process in the limit of an infinite mean free path which does not require any statistical assumptions. It attributes the damping of the collective motion to real transitions from the collective state to degenerate, more complicated nucelar states. The dissipation is described through wave packets which solve an approximate Schroedinger equation within extended subspaces, larger than the original subspace of the undamped motion. When … more
Date: July 1, 1982
Creator: Yannouleas, C.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Axial asymmetry in the IBA and an extensive new 0(6) region near A=130

Description: Although the IBA-1 contains no solutions corresponding to a rigid triaxial shape, it does contain an effective asymmetry arising from zero point motion in a ..gamma..-soft potential leading to a non-zero mean or rms ..gamma... In the consistent Q Formalism (CQF) of the IBA, most results of calculation depend only on one parameter chi. A relation will be established between chi and the effective asymmetry parameter ..gamma... The relation between the asymmetry occurring naturally in IBA-1 and th… more
Date: January 1, 1984
Creator: Carsten, R. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear inertia for fission in a generalized cranking model

Description: The Inglis cranking model has been widely used to calculate the nuclear inertia associated with collective degrees of freedom. After the inclusion of pairing correlations, theoretical results obtained with the cranking model for nuclear rotations and ..gamma..-vibrations were in relatively good agreement with experimental data. Calculations of ..beta..-vibrational inertias were also performed in the cranking model for fission deformations. Theoretical results were several times the irrotational… more
Date: January 1, 1984
Creator: Kunz, J. & Nix, J. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The dynamics of fragment formation

Description: We demonstrate that in the Quantum Molecular Dynamics model, dynamical correlations can result in the production rate for final state nucleon clusters (and hence composite fragments) being higher than would be expected if statistics and the available phase space were dominant in determining composite formation. An intranuclear cascade or a Boltzmann-Uehling-Uhlenbeck model, combined with a statistical approach in the late stage of the collision to determine composites, provides an equivalent de… more
Date: September 1, 1994
Creator: Keane, D. & Collaboration, EOS
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A SHELL MODEL THEORY OF THE R-MATRIX

Description: A method for dealing with the nuclear many-body problem is suggested. The approach is a refinement of the shell model in which the asymptotic boundary conditions are used as constraints in a variational calculation of the R-matrix. Since it is the R-matrix that is calculated, this method should provide a description of nuclear reactions and decays as well as of nuclear bound states. (auth)
Date: August 1, 1962
Creator: Tobocman, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical Reaction Cross Sections for Alpha Particles With an Optical Model

Description: The transmission coefficients T/sub l/ and total reaction cross sections sigma /sub R/ for alpha particles from 0 to 46 Mev interacting with twenty target nuclei with atomic numbers from 10 to 92 are calculated with optical model program in which a previously determined complex nuclear potential is utilized. The dependence of the T/sub l/ values, and hence of sigma /sub R/, on the Woods- Saxon parameters is investigated as a function of projectile energy. The optical model reaction cross sectio… more
Date: May 1, 1961
Creator: Huizenga, J. R. & Igo, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relativistic nuclear dynamics

Description: A review is presented of three distinct approaches to the construction of relativistic dynamical models: (1) Relativistic canonical quantum mechanics. (The Hilbert space of states is independent of the interactions, which are introduced by modifying the energy operator.) (2) Hilbert spaces of manifestly covariant wave functions. (The interactions modify the metric of the Hilbert space.) (3) Covariant Green functions. In each of the three approaches the focus is on the formulation of the two-bod… more
Date: January 1, 1985
Creator: Coester, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SO/sub 8/ model of collectivity in nuclei

Description: The interacting boson model (IBM) has been very successful in giving a unified and simple description of the spectroscopic properties of a wide range of nuclei, from vibrational through rotational nuclei. The three basic assumptions of the model are that (1) the valence nucleons move about a doubly closed core, (2) the collective low-lying states are composed primarily of coherent pairs of neutrons and pairs of protons coupled to angular momentum zero and two and (3) these coherent pairs are ap… more
Date: January 1, 1983
Creator: Ginocchio, J.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Isospin effects in nuclear vibrations

Description: A review of the evidence that the ratio of neutron and proton multipole matrix elements for collective vibrations in single-closed-shell nuclei differ systematically from N/Z is presented. A theoretical framework is given for understanding the data on the basis of the ideas of core polarization. It follows that nuclear deformation parameters are probe dependent and that analysis of excitations by two different probes such as (p,p') and (n,n') can, in principle, give the ratio M/sub n//M/sub p/.… more
Date: September 1, 1984
Creator: Madsen, V.A. & Brown, V.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic radius of the deuteron

Description: The root-mean square radius of the deuteron magnetic moment distribution, r{sub Md}, is calculated for several realistic models of the NN-interaction. For the Paris potential the result is r{sub Md} = 2.312 {+-} 0.010 fm. The dependence of r{sub Md} on the choice of NN model, relativistic effects and meson exchange currents is investigated. The experimental value of r{sub Md} is also considered. The necessity of new precise measurements of the deuteron magnetic form factor at low values of Q{su… more
Date: August 1, 1998
Creator: Afanasev, Andrei; Afanasev, V.D. & Trubnikov, S.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cross section of electron - off-shell nucleon interaction

Description: The results of theoretical calculations of the electron-bound nucleon interaction cross section ({sigma}{sub eN}) are given for four theoretical approaches. It is shown that there are significant differences between predictions of these methods, especially for the deeply bound (high internal momentum, high removing energy) nucleons. To test these predictions experimentally the authors study of cross sections obtained for two primary energies or for bound proton and neutron. These ratios will be… more
Date: January 1, 1993
Creator: Egiyan, K. & Sargsyan, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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