132 research outputs found
Interval type-2 fuzzy logic based multiclass ANFIS algorithm for real-time EEG based movement control of a robot arm
Spontaneous heavy cluster emission rates using microscopic potentials
The nuclear cluster radioactivities have been studied theoretically in the
framework of a microscopic superasymmetric fission model (MSAFM). The nuclear
interaction potentials required for binary cold fission processes are
calculated by folding in the density distribution functions of the two
fragments with a realistic effective interaction. The microscopic nuclear
potential thus obtained has been used to calculate the action integral within
the WKB approximation. The calculated half lives of the present MSAFM
calculations are found to be in good agreement over a wide range of observed
experimental data.Comment: 4 pages, 4 figure
Folding model analysis of proton scattering from mirror nuclei Ne and O
The elastic and inelastic scattering of protons from mirror nuclei Ne
and O are studied in a folding model approach. For comparison, two
different effective interactions are folded with Hartree-Fock densities to
obtain the nuclear interaction potentials. Both of them provide equivalent
descriptions to the data and the deformation parameters extracted from
inelastic scattering are reasonable. The density dependence parameters obtained
from nuclear matter calculations and used for present analysis also provide a
good estimate for the nuclear mean free path. The present formalism unifies
radioactivity, nuclear matter and nuclear scattering.Comment: 12 pages including 5 figure
Role of effective interaction in nuclear disintegration processes
A simple superasymmetric fission model using microscopically calculated
nuclear potentials has shown itself to be outstandingly successful in
describing highly asymmetric spontaneous disintegration of nuclei into two
composite nuclear fragments. The nuclear interaction potentials required to
describe these nuclear decay processes have been calculated by double folding
the density distribution functions of the two fragments with a realistic
effective interaction. The microscopic nucleus-nucleus potential thus obtained,
along with the Coulomb interaction potential and the minimum centrifugal
barrier required for the spin-parity conservation, has been used successfully
for the lifetime calculations of these nuclear disintegration processes.Comment: 7 page
Nuclear Half-Lives for Alpha Radioactivity of Elements with 100 Z 130
Theoretical estimates for the half lives of about 1700 isotopes of heavy
elements with Z from 100 to 130 are tabulated using theoretical Q-values. The
quantum mechanical tunneling probabilities are calculated within a WKB
framework using microscopic nuclear potentials. The microscopic nucleus-nucleus
potentials are obtained by folding the densities of interacting nuclei with a
density dependent M3Y (DDM3Y) effective nucleon-nucleon interaction. The
alpha-decay half lives calculated in this formalism using the experimental
Q-values were found to be in good agreement over a wide range of experimental
data spanning about twenty orders of magnitude. The theoretical Q-values used
for the present calculations are extracted from three different mass estimates
viz. Myers-Swiatecki [MS], Muntian-Hofmann-Patyk-Sobiczewski [M] and
Koura-Tachibana-Uno-Yamada [KUTY].Comment: 57 pages, 2 tables, 1 figur
Cluster radioactivity in very heavy nuclei: a new perspective
Exotic cluster decay of very heavy nuclei is studied using the microscopic
nuclear potentials obtained by folding density dependent M3Y effective
interaction with the densities of the cluster and the daughter nuclei. The
microscopic nuclear potential, Coulomb interaction and the centrifugal barrier
arising out of spin-parity conservation are used to obtain the potential
between the cluster and the daughter nuclei. Half life values are calculated in
the WKB framework and the preformation factors are extracted. The latter values
are seen to have only a very weak dependence on the mass of the emitted
cluster.Comment: 4 pages including 2 table
Photonuclear reactions of actinides in the giant dipole resonance region
Photonuclear reactions at energies covering the giant dipole resonance (GDR)
region are analyzed with an approach based on nuclear photoabsorption followed
by the process of competition between light particle evaporation and fission
for the excited nucleus. The photoabsorption cross section at energies covering
the GDR region is contributed by both the Lorentz type GDR cross section and
the quasideuteron cross section. The evaporation-fission process of the
compound nucleus is simulated in a Monte-Carlo framework. Photofission reaction
cross sections are analyzed in a systematic manner in the energy range of
10-20 MeV for the actinides Th, U and Np.
Photonuclear cross sections for the medium-mass nuclei Cu and Zn,
for which there are no fission events, are also presented. The study reproduces
satisfactorily the available experimental data of photofission cross sections
at GDR energy region and the increasing trend of nuclear fissility with the
fissility parameter for the actinides.Comment: 4 pages including 2 tables and 1 figur
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The long-term price-earnings ratio
price-earnings ratio;value premium;arbitrage trading rule;UK stock returns;contrarian investment
Abstract: The price-earnings effect has been thoroughly documented and is the subject of numerous academic studies. However, in existing research it has almost exclusively been calculated on the basis of the previous year's earnings. We show that the power of the effect has until now been seriously underestimated due to taking too short-term a view of earnings. Looking at all UK companies since 1975, using the traditional P/E ratio we find the difference in average annual returns between the value and glamour deciles to be 6%. This is similar to other authors' findings. We are able to almost double the value premium by calculating the P/E ratio using earnings averaged over the previous eight years
Spin polarised nuclear matter and its application to neutron stars
An equation of state(EOS) of nuclear matter with explicit inclusion of a
spin-isospin dependent force is constructed from a finite range, momentum and
density dependent effective interaction. This EOS is found to be in good
agreement with those obtained from more sophisticated models for unpolarised
nuclear matter. Introducing spin degrees of freedom, it is found that at
density about 2.5 times the density of normal nuclear matter the neutron matter
undergoes a ferromagnetic transition. The maximum mass and the radius of the
neutron star agree favourably with the observations. Since finding quark matter
rather than spin polarised nuclear matter at the core of neutron stars is more
probable, the proposed EOS is also applied to the study of hybrid stars. It is
found using the bag model picture that one can in principle describe both the
mass and size as well as the surface magnetic field of hybrid stars
satisfactorily.Comment: 26 pages, 11 figures available on reques
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