58,398 research outputs found
Generator Coordinate Calculations for the Breathing-Mode Giant Monopole Resonance in Relativistic Mean Field Theory
The breathing-mode giant monopole resonance (GMR) is studied within the
framework of the relativistic mean-field theory using the Generator Coordinate
Method (GCM). The constrained incompressibility and the excitation energy of
isoscalar giant monopole states are obtained for finite nuclei with various
sets of Lagrangian parameters. A comparison is made with the results of
nonrelativistic constrained Skyrme Hartree-Fock calculations and with those
from Skyrme RPA calculations. In the RMF theory the GCM calculations give a
transition density for the breathing mode, which resembles much that obtained
from the Skyrme HF+RPA approach and also that from the scaling mode of the GMR.
From the systematic study of the breathing-mode as a function of the
incompressibility in GCM, it is shown that the GCM succeeds in describing the
GMR energies in nuclei and that the empirical breathing-mode energies of heavy
nuclei can be reproduced by forces with an incompressibility close to
MeV in the RMF theory.Comment: 27 pages (Revtex) and 5 figures (available upon request), Preprint
MPA-793 (March 1994
Isospin Dependence of the Spin-Orbit Force and Effective Nuclear Potentials,
The isospin dependence of the spin-orbit potential is investigated for an
effective Skyrme-like energy functional suitable for density dependent
Hartree-Fock calculations. The magnitude of the isospin dependence is obtained
from a fit to experimental data on finite spherical nuclei. It is found to be
close to that of relativistic Hartree models. Consequently, the anomalous kink
in the isotope shifts of Pb nuclei is well reproduced.Comment: Revised, 11 pages (Revtex) and 2 figures available upon request,
Preprint MPA-833, Physical Review Letters (in press)
Underwater detection of dangerous substances: status the SABAT project
The Neutron Activation Analysis (NAA) plays an exceptional role in the modern
nuclear engineering, especially in detection of hazardous substances. However,
in the aquatic environment, there are still many problems to be solved for
effective usage of this technique. We present status of SABAT (Stoichiometry
Analysis By Activation Techniques), one of the projects aiming at construction
of an underwater device for non-invasive threat detection based on the NAA
Laboratory and theoretical investigation of chemical release experiment Final report, 8 Oct. 1965 - 10 Nov. 1966
Chemical release experiments in upper atmospher
Quantifying the risk of heart disease following acute ischaemic stroke: a meta-analysis of over 50 000 participants
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