76 research outputs found
Structure and decay properties of spin-dipole giant resonances within a semimicroscopical approach
A semimicroscopical approach is applied to calculate: (i) strength functions
for the charge-exchange spin-dipole giant resonances in the 208Pb parent
nucleus; (ii) partial and total branching ratios for the direct proton decay of
the resonance in 208Bi. The approach is based on continuum-RPA calculations of
corresponding reaction-amplitudes and phenomenological description of the
doorway-state coupling to many-quasiparticle configurations. The only
adjustable parameter needed for the description is found by comparison of the
calculated and experimental total widths of the resonance. Other model
parameters used in calculations are taken from independent data. The calculated
total branching ratio is found to be in reasonable agreement with the
experimental value.Comment: 15 pages, 4 figures, submitted to Phys. Lett.
Semimicroscopical description of the simplest photonuclear reactions accompanied by excitation of the giant dipole resonance in medium-heavy mass nuclei
A semimicroscopical approach is applied to describe photoabsorption and
partial photonucleon reactions accompanied by the excitation of the giant
dipole resonance (GDR). The approach is based on the continuum-RPA (CRPA) with
a phenomenological description for the spreading effect. The phenomenological
isoscalar part of the nuclear mean field, momentum-independent Landau-Migdal
particle-hole interaction, and separable momentum-dependent forces are used as
input quantities for the CRPA calculations. The experimental photoabsorption
and partial -reaction cross sections in the vicinity of the GDR are
satisfactorily described for Y, Ce and Pb target nuclei.
The total direct-neutron-decay branching ratio for the GDR in Ca and
Pb is also evaluated.Comment: 19 pages, 5 eps figure
Feasibility studies for the measurement of time-like proton electromagnetic form factors from p¯ p→ μ+μ- at P ¯ ANDA at FAIR
This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, | GE| and | GM| , using the p¯ p→ μ+μ- reaction at P ¯ ANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at P ¯ ANDA , using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is p¯ p→ π+π-, due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented
Psycho-social correlates of medication serum levels in patients with seizures: implications for education of patients
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67536/2/10.1177_001789697002900301.pd
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