Results 251 to 260 of about 5,497,257 (293)

Nuclear Level Densities Calculations

Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ), 2021
There is a need to determine nuclear level densities since experiments that defect nuclear level densities can not observe some of these densities, because of experimental limitations. The missed level could be calculated using standard correction of Porter-Thomas width distribution.
openaire   +1 more source

Nuclear Level Densities

Physical Review, 1957
By using the statistical methods originally due to Bethe, the predictions for the densities of nuclear energy levels at excitation energies around 8 Mev are examined for two different versions of the shell model. A crude method is used to take into account the effects of shell structure. The assumed form of the theoretical expression for the density of
openaire   +1 more source

Estimations of level density parameters by using artificial neural network for phenomenological level density models

Applied Radiation and Isotopes, 2021
The main aim of this study is to develop accurate artificial neural network (ANN) algorithms to estimate level density parameters. An efficient Bayesian-based algorithm is presented for classification algorithms. Unknown model parameters are estimated using the observed data, from which the Bayesian-based algorithm is predicted.
Hasan Özdoğan, Yiğit Ali Üncü, Mert Şekerci, Abdullah Kaplan   +3 more
openaire   +5 more sources

LEARNING RATES FOR DENSITY LEVEL DETECTION

Analysis and Applications, 2005
In this paper, we address learning rates for the density level detection (DLD) problem. We begin by proving a "No Free Lunch Theorem" showing that rates cannot be obtained in general. Then, we apply a recently established classification framework to obtain rates for DLD support vector machines under mild assumptions on the density.
Scovel, Clint, Hush, Don, Steinwart, Ingo   +2 more
openaire   +1 more source

Nuclear shell model and level density

International Journal of Modern Physics E, 2020
The accurate knowledge of the nuclear level density is crucial for understanding the nuclear structure and for numerous applications including astrophysical reactions. In this review paper, we discuss the shell-model description of the nuclear level density, the use of the statistical moments method and underlying physics. The level density found with
Vladimir Zelevinsky, Sofia Karampagia
openaire   +1 more source

Nuclear level densities at high excitations

Physical Review C, 1992
We calculate level densities for {sup 20}Ne, {sup 40}Ca, and {sup 100}Ru nuclei using unrestricted uniform, single particle levels (Fermi gas) and for realistic levels restricted to those bound by centripetal and Coulomb forces. For the latter we use single particle levels due to Seeger, and results for a Woods-Saxon model.
, Mustafa, , Blann, , Ignatyuk, , Grimes
openaire   +2 more sources

Lipid levels and bone mineral density

The American Journal of Medicine, 2005
There has been considerable debate about the potential relationship between the use of statin lipid-lowering drugs and fracture risk; several observational studies suggest a protective effect but no randomized controlled trials have confirmed such a benefit.
Daniel H, Solomon, Jerry, Avorn, Claire F, Canning, Philip S, Wang   +3 more
openaire   +2 more sources

Theory of Nuclear Level Density

Physical Review, 1954
We have compared the level density of a nuclear model deduced from a statistical analysis with the results of the exact counting of the levels of the same model. The tables of levels of ${\mathrm{Ne}}^{20}$ given by Critchfield and Oleksa have been used as a test of the statistical theory. A new derivation of the level density is presented.
openaire   +2 more sources

Level and State Densities

1994
Abstract In the statistical model of nuclear reactions, discussed in the next chapter, the basic hypothesis is made of the formation of a fully equilibrated compound nucleus whose decay is independent of the mode of formation and entirely governed by the phase space available to the reaction products (Weisskopf and Ewing 1940). A similar
E Gadioli, P E Hodgson
openaire   +1 more source

NUCLEAR LEVEL DENSITY AT FINITE TEMPERATURES

International Journal of Modern Physics E, 2006
Selfconsistent mean-field calculations have been performed with the SkM* Skyrme force for 140 spherical even-even nuclei at temperatures 0≤T≤4 MeV . Single-particle level densities for this sample of nuclei are determined for various temperatures. The average dependence of the single-particle level density on mass number A and isospin is given and ...
Bartel, J., Pomorski, K., Nerlo-Pomorska, B.   +2 more
openaire   +1 more source