1,745 research outputs found
Comparison of calculated radiochemical cross sections with experimental results for incident protons and negative pions in the 50 to 400 MeV region - Effect of varying a few nuclear parameters in the calculations
Effect of varying nuclear parameters in calculating radiochemical cross sections for incident proton and negative pion reactions in 50 to 400 MeV regio
Literature Survey of Radiochemical Cross-section Data Below 425 Mev
Literature survey of radiochemical cross sections below 425 Me
Bridge Hopping on Conducting Polymers in Solution
Configurational fluctuations of conducting polymers in solution can bring
into proximity monomers which are distant from each other along the backbone.
Electrons can hop between these monomers across the "bridges" so formed. We
show how this can lead to (i) a collapse transition for metallic polymers, and
(ii) to the observed dramatic efficiency of acceptor molecules for quenching
fluorescence in semiconducting polymers.Comment: RevTeX 12 pages + 2 Postscript figure
Instructions for the operation of codes associated with the low-energy intranuclear cascade calculation
Instructions for cascade code calculations of incident nucleon and charged pion low energies resulting from intranuclear collision
Representative results in graphical form from computer production runs of the low-energy intranuclear-cascade calculation
Computer production runs of low energy intranuclear cascade calculation in graphical for
Explicitly correlated trial wave functions in Quantum Monte Carlo calculations of excited states of Be and Be-
We present a new form of explicitly correlated wave function whose parameters
are mainly linear, to circumvent the problem of the optimization of a large
number of non-linear parameters usually encountered with basis sets of
explicitly correlated wave functions. With this trial wave function we
succeeded in minimizing the energy instead of the variance of the local energy,
as is more common in quantum Monte Carlo methods. We applied this wave function
to the calculation of the energies of Be 3P (1s22p2) and Be- 4So (1s22p3) by
variational and diffusion Monte Carlo methods. The results compare favorably
with those obtained by different types of explicitly correlated trial wave
functions already described in the literature. The energies obtained are
improved with respect to the best variational ones found in literature, and
within one standard deviation from the estimated non-relativistic limitsComment: 19 pages, no figures, submitted to J. Phys.
Stochastic interacting particle systems out of equilibrium
This paper provides an introduction to some stochastic models of lattice
gases out of equilibrium and a discussion of results of various kinds obtained
in recent years. Although these models are different in their microscopic
features, a unified picture is emerging at the macroscopic level, applicable,
in our view, to real phenomena where diffusion is the dominating physical
mechanism. We rely mainly on an approach developed by the authors based on the
study of dynamical large fluctuations in stationary states of open systems. The
outcome of this approach is a theory connecting the non equilibrium
thermodynamics to the transport coefficients via a variational principle. This
leads ultimately to a functional derivative equation of Hamilton-Jacobi type
for the non equilibrium free energy in which local thermodynamic variables are
the independent arguments. In the first part of the paper we give a detailed
introduction to the microscopic dynamics considered, while the second part,
devoted to the macroscopic properties, illustrates many consequences of the
Hamilton-Jacobi equation. In both parts several novelties are included.Comment: 36 page
Simulation of Atmospheric Muon and Neutrino Fluxes with CORSIKA
The fluxes of atmospheric muons and neutrinos are calculated by a three
dimensional Monte Carlo simulation with the air shower code CORSIKA using the
hadronic interaction models DPMJET, VENUS, GHEISHA, and UrQMD. For the
simulation of low energy primary particles the original CORSIKA has been
extended by a parametrization of the solar modulation and a microscopic
calculation of the directional dependence of the geomagnetic cut-off functions.
An accurate description for the geography of the Earth has been included by a
digital elevation model, tables for the local magnetic field in the atmosphere,
and various atmospheric models for different geographic latitudes and annual
seasons. CORSIKA is used to calculate atmospheric muon fluxes for different
locations and the neutrino fluxes for Kamioka. The results of CORSIKA for the
muon fluxes are verified by an extensive comparison with recent measurements.
The obtained neutrino fluxes are compared with other calculations and the
influence of the hadronic interaction model, the geomagnetic cut-off and the
local magnetic field on the neutrino fluxes is investigated.Comment: revtex, 19 pages, 19 Postscript figures, submitted to Phys. Rev.
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