90 research outputs found
Isoscalar dipole strength in ^{208}_{82}Pb_{126}: the spurious mode and the strength in the continuum
Isoscalar dipole (compression) mode is studied first using schematic
harmonic-oscillator model and, then, the self-consistent Hartree-Fock (HF) and
random phase approximation (RPA) solved in coordinate space. Taking ^{208}Pb
and the SkM* interaction as a numerical example, the spurious component and the
strength in the continuum are carefully examined using the sum rules. It is
pointed out that in the continuum calculation one has to use an extremely fine
radial mesh in HF and RPA in order to separate, with good accuracy, the
spurious component from intrinsic excitations.Comment: 19 pages, 2 figure
Isoscalar Giant Dipole Resonance and Nuclear Matter Incompressibility Coefficient
We present results of microscopic calculations of the strength function,
S(E), and alpha-particle excitation cross sections sigma(E) for the isoscalar
giant dipole resonance (ISGDR). An accurate and a general method to eliminate
the contributions of spurious state mixing is presented and used in the
calculations. Our results provide a resolution to the long standing problem
that the nuclear matter incompressibility coefficient, K, deduced from sigma(E)
data for the ISGDR is significantly smaller than that deduced from data for the
isoscalar giant monopole resonance (ISGMR).Comment: 4 pages using revtex 3.0, 3 postscript figures created by Mathematica
4.
School organizational culture: The peak of research in the context of neoliberal policies
Inscrita numa matriz teórica multirreferencial, a problemática da cultura organizacional tem sido objecto de múltiplos desenvolvimentos conceptuais e diversificadas apropriações políticas e ideológicas. No campo da educação e no contexto mais específico das organizações escolares, as abordagens culturais e simbólicas sofreram algumas inflexões teóricas apenas compreensíveis quando contextualizadas no quadro mais global das políticas internacionais de cariz neoliberal e neoconservador. Neste trabalho, procura-se reflectir criticamente sobre a forma como a problemática da cultura organizacional em contexto escolar passa a ser (re)perspectivada numa altura em que se expandem alguns objectivos e valores políticos associados às ideologias da modernização e da racionalização. Num segundo momento, tomando como ponto de partida a análise de um vasto número de investigações integradas em quatro bases de dados electrónicas de âmbito internacional, debatemos as principais tendências teóricas, conceptuais e metodológicas deste campo de estudo, fazendo sobressair o lugar e o estatuto da escola enquanto contexto privilegiado de investigação, designadamente nos domínios crítico-reflexivos.Within a multi-referential theoretical framework, the issue of organizational culture has been a subject for multiple conceptual developments and different ideological and political appropriations. In the field of education and in the specific context of school organizations, the cultural and symbolic approaches were subjected to some theoretical inflections. These can only be understood in the global framework of international policies of neoliberal and neoconservative nature. First, this paper critically discusses how the issue of organizational culture in school context was put in perspectives at a time when some political-ideological objectives and values were associated to modernization and rationalization ideologies. Based on the analysis of a great number of researches included in four electronic databases with an international scope, it then discusses the main theoretical, conceptual and methodological trends of this field of study, stressing the place and statute of school as a privileged research context, namely in the reflexive and critical domain.info:eu-repo/semantics/publishedVersio
The Sudbury Neutrino Observatory
The Sudbury Neutrino Observatory is a second generation water Cherenkov
detector designed to determine whether the currently observed solar neutrino
deficit is a result of neutrino oscillations. The detector is unique in its use
of D2O as a detection medium, permitting it to make a solar model-independent
test of the neutrino oscillation hypothesis by comparison of the charged- and
neutral-current interaction rates. In this paper the physical properties,
construction, and preliminary operation of the Sudbury Neutrino Observatory are
described. Data and predicted operating parameters are provided whenever
possible.Comment: 58 pages, 12 figures, submitted to Nucl. Inst. Meth. Uses elsart and
epsf style files. For additional information about SNO see
http://www.sno.phy.queensu.ca . This version has some new reference
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