806 research outputs found
GANIL Status report
The GANIL-Spiral facility (Caen, France) is dedicated to the acceleration of
heavy ion beams for nuclear physics, atomic physics, radiobiology and material
irradiation. The production of radioactive ion beams for nuclear physics
studies represents the main part of the activity. The facility possesses a
versatile combination of equipments, which permits to produce accelerated
radioactive ion beams with two complementary methods: Isotope Separation In
Line (ISOL) and In-Flight Separation techniques (IFS). Considering the future
of GANIL, SPIRAL II projects aims to produce high intensity secondary beams, by
fission induced with a 5 mA deuteron beam on an uranium target.Comment: 5 pages, 5 figures, to be appear in the proceedings of the 17th
International Conference on Cyclotrons and their Application
A Preliminary Checklist of the Moths of Butler County, Ohio
Author Institution: Department of Zoology, Miami UniversityUsing a combination of blacklight, mercury vapor light, and sugar bait sampling techniques, we collected moths over a 2-yr period in Butler County, OH, and compiled a list of 392 species. Seventy-eight percent (305) of these species were found to be new county records. A checklist is provided as a baseline catalogue of the moths of Butler County, OH. An analysis of historical county records revealed a bias towards large or colorful species. Although many species we collected are considered common, several infrequently encountered species were discovered. Our effort suggests that biological surveys in fragmented landscapes may reveal unexpected biological diversity
Functionnal biodiversity in mango orchards on Reunion. Ecosystemic and landscape effects on epigeous predatory arthropods.
The knowledge of factors implicated in agroecosystem diversity is necessary to better evaluate their role. The study aims to link within-field plant diversity, cultural practices, and landscape context with terrestrial predatory arthropods in mango orchards on Reunion. Twenty-four plots distributed within the mango production area have been studied. Arthropods were sampled with pitfall traps. The land plots were grouped into three groups of agricultural practice intensity. The landscape was mapped within a circle of 400 meters around the orchards, which permitted to distinguish three different landscape contexts. Based on 83181 arthropods collected, 65124 were determined as predators, their communities were mainly composed of ants (Hymenoptera: Formicinae) and spiders (Araneae). The species richness and their equitability were influenced by factors at three different scales: (1) the within-field plant diversity improved evenness of predatory arthropods communities; (2) the moderate farming practices, as organic farming practices, had higher species richness than those obtained with “conventionnal” practices; (3) a landscape context with relevant heterogeneity and fragmentation increased the species richness of epigeal predatory arthropods in mango orchards
Mechanical and chemical spinodal instabilities in finite quantum systems
Self consistent quantum approaches are used to study the instabilities of
finite nuclear systems. The frequencies of multipole density fluctuations are
determined as a function of dilution and temperature, for several isotopes. The
spinodal region of the phase diagrams is determined and it appears that
instabilities are reduced by finite size effects. The role of surface and
volume instabilities is discussed. It is indicated that the important chemical
effects associated with mechanical disruption may lead to isospin
fractionation.Comment: 4 pages, 4 figure
Sending femtosecond pulses in circles: highly non-paraxial accelerating beams
We use caustic beam shaping on 100 fs pulses to experimentally generate
non-paraxial accelerating beams along a 60 degree circular arc, moving
laterally by 14 \mum over a 28 \mum propagation length. This is the highest
degree of transverse acceleration reported to our knowledge. Using diffraction
integral theory and numerical beam propagation simulations, we show that
circular acceleration trajectories represent a unique class of non-paraxial
diffraction-free beam profile which also preserves the femtosecond temporal
structure in the vicinity of the caustic
Properties of Be and C deduced from the folding--potential model
The -- differential cross sections are analyzed in the
optical model using a double--folded potential. With the knowledge of this
potential bound and resonance--state properties of --cluster states in
Be and C as well as astrophysical S--factors of
He(,)Be and Be(,)C are
calculated. --widths and B(E2)--values are deduced.Comment: 2 pages LaTeX, 2 figures can be obtained from the author
Arbitrary non-paraxial accelerating periodic beams and spherical shaping of light
We report the observation of arbitrary accelerating beams designed using a
non-paraxial description of optical caustics. We use a spatial light
modulator-based setup and techniques of Fourier optics to generate circular and
Weber beams subtending over 95 degrees of arc. Applying a complementary binary
mask also allows the generation of periodic accelerating beams taking the forms
of snake-like trajectories, and the application of a rotation to the caustic
allows the first experimental synthesis of optical accelerating beams upon the
surface of a sphere in three dimensions.Comment: 4 pages, 4 figures articl
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