9,125,085 research outputs found
Recommended from our members
A practitioner's guide to 'Imagine', the systemic and prospective sustainability analysis
The purpose of the Mediterranean Action Plans Coastal Area Management Programme is to help Mediterranean countries implement a sustainable management process for their coastal areas. This in particular implies thinking collectively about possible futures by taking into account past developments and the present situation of the area in question. To do so and right from the very start, the Blue Plan has assisted teams involved in the CAMPs to use the systemic and prospective approach so as to highlight priorities, forecast negative developments and suggest action to be taken to establish sustainable development in the Mediterranean's coastal areas. What do we mean by sustainable development? The Blue Plan adheres to a definition that is a blend of what you find in the Bruntland Report and at the FAO, 'sustainable development is one that respects the environment, is technically appropriate, economically viable and socially acceptable, making it possible to meet the needs of present generations without jeopardising the ability of future generations to meet their own needs'.
In this framework the 'Imagine' analysis of systemic and prospective sustainability now proposes a set of tools and methods (a methodological corpus) to describe, assess and examine the level of sustainability of an eco-socio system in the past, present and future by means of indicators and a participatory process that considers local actors to be experts at their level
A search for the fourth SM family quarks at Tevatron
It is shown that the fourth standard model (SM) family quarks can be observed
at the Fermilab Tevatron if their anomalous interactions with known quarks have
sufficient strength.Comment: 7 pages, 2 tables, 4 figure
Exotic Baryons and Monopole Excitations in a Chiral Soliton Model
We compute the spectra of exotic pentaquarks and monopole excitations of the
low--lying and baryons in a chiral soliton model. Once the
low--lying baryon properties are fit, the other states are predicted without
any more adjustable parameters. This approach naturally leads to a scenario in
which the mass spectrum of the next to lowest--lying states is
fairly well approximated by the ideal mixing pattern of the
representation of flavor SU(3). We compare
our results to predictions obtained in other pictures for pentaquarks and
speculate about the spin--parity assignment for and Comment: 16 pages, 2 figures, 6 table
Measurement of the LT-asymmetry in \pi^0 electroproduction at the energy of the \Delta (1232) resonance
The reaction p(e,e'p)pi^0 has been studied at Q^2=0.2 (GeV/c)^2 in the region
of W=1232 MeV. From measurements left and right of q, cross section asymmetries
\rho_LT have been obtained in forward kinematics \rho_LT(\theta_\pi^0=20deg) =
(-11.68 +/- 2.36_stat +/- 2.36_sys)$ and backward kinematics
\rho_LT(\theta_\pi^0=160deg) =(12.18 +/- 0.27_stat +/- 0.82_sys). Multipole
ratios \Re(S_1+^* M_1+)/|M_1+|^2 and \Re(S_0+^* M_1+)/|M_1+|^2 were determined
in the framework of the MAID2003 model. The results are in agreement with older
data. The unusally strong negative \Re(S_0+^* M_1+)/|M_1+|^2 required to bring
also the result of Kalleicher et al. in accordance with the rest of the data is
almost excluded.Comment: 7 pages, 7 figures, 4 tables. Changed content. Accepted for
publication in EPJ
A Covariant Path Amplitude Description of Flavour Oscillations: The Gribov-Pontecorvo Phase for Neutrino Vacuum Propagation is Right
An extended study is performed of geometrical and kinematical assumptions
used in calculations of the neutrino oscillation phase. The almost universally
employed `equal velocity' assumption, in which all neutrino mass eigenstates
are produced at the same time, is shown to underestimate, by a factor of two,
the neutrino propagation contribution to the phase. Taking properly into
account, in a covariant path amplitude calculation, the incoherent nature of
neutrino production as predicted by the Standard Model, results in an important
source propagator contribution to the phase. It is argued that the commonly
discussed Gaussian `wave packets' have no basis within quantum mechanics and
are the result of a confused amalgam of quantum and classical wave concepts.Comment: 39 pages, 1 table, 1 figure. Subject matter similar to
hep-ph/0110064, hep-ph/0110066. More pedagogical presentation addressing
referee criticism of earlier paper
Spatially Dependent Quantum Interference Effects in the Detection Probability of Charged Leptons Produced in Neutrino Interactions or Weak Decay Processes
Feynman's path amplitude formulation of quantum mechanics is used to analyse
the production of charged leptons from charged current weak interaction
processes. For neutrino induced reactions the interference effects predicted
are usually called `neutrino oscillations'. Similar effects in the detection of
muons from pion decay are here termed `muon oscillations'. Processes considered
include pion decay (at rest and in flight), and muon decay and nuclear
-decay at rest. In all cases studied, a neutrino oscillation phase
different from the conventionally used one is found. A concise critical review
is made of previous treatments of the quantum mechanics of neutrino and muon
oscillations.Comment: 45 pages, 1 table, 3 figures. Supersedes hep-ph/0110064. Consistent
use of MRS matrix to describe charged lepton-neutrino couplings. Unphysical
`lepton flavour eigenstates' removed from the formalis
Creating Ioffe-Pritchard micro-traps from permanent magnetic film with in-plane magnetization
We present designs for Ioffe-Pritchard type magnetic traps using planar
patterns of hard magnetic material. Two samples with different pattern designs
were produced by spark erosion of 40 m thick FePt foil. The pattern on the
first sample yields calculated axial and radial trap frequencies of 51 Hz and
6.8 kHz, respectively. For the second sample the calculated frequencies are 34
Hz and 11 kHz. The structures were used successfully as a magneto-optical trap
for Rb and loaded as a magnetic trap. A third design, based on
lithographically patterned 250 nm thick FePt film on a Si substrate, yields an
array of 19 traps with calculated axial and radial trap frequencies of 1.5 kHz
and 110 kHz, respectively.Comment: 8 pages, 5 figures Revised and accepted for EPJD, improved picture
Sea quark polarization and semi-inclusive DIS data
We investigate the potential impact of forthcoming Jefferson Lab
semi-inclusive polarized deep inelastic scattering proton measurements in the
determination of the sea quark polarization in the nucleon by means of a next
to leading order global QCD analysis. Specifically, we estimate the resulting
improvement in the constraints on polarized parton densities for the different
flavors, which is found to be significant for up and strange quarks, and the
correlation between remaining uncertainty ranges for each of the parton
species.Comment: 7 pages, 4 figures. Version to be published in the European Physical
Journal
Near-threshold production of omega mesons in the pn -> d omega reaction
The first measurement of the p n -> d omega total cross section has been
achieved at mean excess energies of Q = 28 and 57 MeV by using a deuterium
cluster-jet target. The momentum of the fast deuteron was measured in the ANKE
spectrometer at COSY-Juelich and that of the slow "spectator" proton p(sp) from
the p d -> p(sp) d omega reaction in a silicon telescope placed close to the
target. The cross sections lie above those measured for p p -> p p omega but
seem to be below theoretical predictions.Comment: 7 pages, 8 figures; second approach to describe the background has
been added; results changed insignificantly, EPJ in pres
Circular 58
A comparative yield trial with 44 named varieties and numbered selections of
potatoes was conducted at the University of Alaska-Fairbanks, Agricultural and
Forestry Experiment Station’s (AFES) Palmer Research Center during the 1986
growing season. This yield trial is the continuation of a potato variety testing program
initiated in 1982. The trial again was conducted at the Matanuska Research
Farm, located on Trunk Road near Palmer. Nonirrigated trials have been conducted
each year beginning in 1982, but irrigated trials were not initiated until
1985. Results of previous trials are recorded in Circulars 49 and 54, available
at the Agricultural and Forestry Experiment Station offices in Fairbanks and Palmer.
As in past years, varieties with long production histories in Alaska (Alaska 114,
Bakeking, Green Mountain, Kennebec, Superior) are included and serve as a comparative
base for newly developed varieties or older varieties that in the past have
escaped testing at this location. Varieties that compare favorably with the above
listed standards may warrant some consideration by commercial growers.
In continuance of a program that was initiated in 1985, abbreviated versions
of the AFES potato yield trial were conducted at locations in various parts of the
state. These off-station trials again were made possible by the willingness of
cooperators to plant, tend and harvest the crop. The seven off-station sites include
several where comparative testing of potato varieties has not been reported
previously.Introduction -- Matanuska Farm Yield Trials: Cultural Practices - Environmental Conditions, Results, Discussion -- Trials at Other Locations in Alaska: General Procedures, Specific Site Information: Ambler, Copper Center, Delta Junction, Fairbanks, Kake, Kodiak, Noorvi
- …