87 research outputs found
Torts - Implied Warranty - Pharmacists\u27 Liability for Use of Manufacturer\u27s Sealed Packets
Ground State Wave Functions in the Hyperspherical Formalism for Nuclei with A > 4
The general formulation of a technically advantageous method to find the
ground state solution of the Schrodinger equation in configuration space for
systems with a number of particles A greater than 4 is presented. The wave
function is expanded in pair correlated hyperspherical harmonics beyond the
lowest order approximation and then calculated in the Faddeev approach. A
recent efficient recursive method to construct antisymmetric A-particle
hyperspherical harmonics is used. The accuracy is tested for the bound state
energies of nuclei with A = 6,8,12. The high quality of the obtained results
becomes evident from a comparison with other approaches.Comment: 17 pages, 1 figure, Submitted to Nucl. Phys.
Application of powder electrodes for wear-resistant surfacing knives for the recycling of PET waste
Shell model study of the isobaric chains A=50, A=51 and A=52
Shell model calculations in the full pf-shell are carried out for the A=50,
51 and 52 isobars. The most frequently used effective interactions for the
pf-shell, KB3 and FPD6 are revisited and their behaviour at the N=28 and Z=28
closures examined. Cures to their -relatively minor- defaults are proposed, and
a new mass dependent version called KB3G is released. Energy spectra,
electromagnetic transitions and moments as well as beta decay properties are
computed and compared with the experiment and with the results of the earlier
interactions. A high quality description is achieved. Other miscellaneous
topics are addressed; the Coulomb energy differences of the yrast states of the
mirror pair 51Mn-51Fe and the systematics of the magnetic moments of the N=28
isotones.Comment: 45 pages, 34 figures, Latex. Submitted for publicatio
State Dependent Effective Interaction for the Hyperspherical Formalism with Noncentral Forces
The recently developed effective interaction method for the hyperspherical
harmonic formalism is extended to noncentral forces. Binding energies and radii
of three- and four-body nuclei are calculated with AV6 and AV14 NN potentials.
Excellent results for the convergence of the expansion are found, particularly
for the three-nucleon system. Due to the higher density the convergence rate is
a bit slower for the alpha particle. In comparison to central potential models
there is only a very slight deterioration of the convergence due the tensor
force, while other potential terms have no visible effect on the convergence.
The obtained values for binding energy and radii also agree well with the
results in the literature obtained with other few-body techniques.Comment: LaTeX, 12 pages, 6 ps figures, Figures in correct order in this
replacemen
Unsupervised Classification by Iterative Voting
In the paper we present a simple algorithm for unsupervised classification of given items by a group of agents. The purpose of the algorithm is to provide fast and computationally light solutions of classification tasks by the randomly chosen agents. The algorithm follows basic techniques of plurality voting and combinatorial stable matching and does not use additional assumptions or information about the levels of the agents’ expertise. Performance of the suggested algorithm is illustrated by its application to simulated and real-world datasets, and it was demonstrated that the algorithm provides close to correct classifications. The obtained solutions can be used both separately and as initial classifications in more complicated algorithms
State Dependent Effective Interaction for the Hyperspherical Formalism
The method of effective interaction, traditionally used in the framework of
an harmonic oscillator basis, is applied to the hyperspherical formalism of
few-body nuclei (A=3-6). The separation of the hyperradial part leads to a
state dependent effective potential. Undesirable features of the harmonic
oscillator approach associated with the introduction of a spurious confining
potential are avoided. It is shown that with the present method one obtains an
enormous improvement of the convergence of the hyperspherical harmonics series
in calculating ground state properties, excitation energies and transitions to
continuum states.Comment: LaTeX, 16 pages, 8 ps figure
Particle-Number Reprojection in the Shell Model Monte Carlo Method: Application to Nuclear Level Densities
We introduce a particle-number reprojection method in the shell model Monte
Carlo that enables the calculation of observables for a series of nuclei using
a Monte Carlo sampling for a single nucleus. The method is used to calculate
nuclear level densities in the complete -shell using a good-sign
Hamiltonian. Level densities of odd-A and odd-odd nuclei are reliably extracted
despite an additional sign problem. Both the mass and the dependence of
the experimental level densities are well described without any adjustable
parameters. The single-particle level density parameter is found to vary
smoothly with mass. The odd-even staggering observed in the calculated
backshift parameter follows the experimental data more closely than do
empirical formulae.Comment: 14 pages, 4 eps figures included, RevTe
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