143 research outputs found
Domesticating forests : how farmers manage forest resources
Local people in South-east Asia are often cited as skilled forest managers. It is barely acknowledged that an essential part of this forest management does not concern natural forests, but forests that have been planted, often after the removal of pre-existing natural forests; forests that are cultivated not by professional foresters, but by sedentary or swidden farmers, on their farmlands; forests that are based not on exotic, fast-growing trees, but on local tree species, and harbour an incredible variety of plant and animal species. This book concentrates on forest cultivation by smallholder farmers in South-east Asia, not only because it constitutes altogether the most original and lesser known aspect of local forest management in the region, but also because, it represents the most promising field for the design of alternative strategies for the management of forest resources and forest lands. Natural forests are still present and actively managed in the region. So, why do people cut natural forests to replant the same species of forest trees they have just chopped down? Why have professional foresters, or the decision-makers in forest management, never seriously considered these examples of indigenous forest culture, however sustainable and profitable they may be? Many elements of the answer to these questions are given in this book, which is built on the conclusions of 10 years of multidisciplinary research and analysis on these systems. It shows how forest culture by farmers constitutes a strategy that questions the practical, conceptual and legal aspects of conventional forest management. It speaks for more scientific and political support to these systems, because they are altogether neglected, endangered and full of potential. Further it explains a why it is important to consider these examples as interesting alternative models to either forest extraction or specialized forest plantations, especially in the present context of depletion of natural forests all over the planet. Can the transfer of these original examples to other parts of the world be achieved? How can it be successful? This book helps to answer these important questions
Heavy Flavour Physics at HERA - a Survey
At the HERA collider at DESY, high energy electron and positron beams
interact with proton beams. A review is presented of the variety of ways in
which these collisions produce final states containing charm and beauty quarks.Comment: 45 pages including 30 figures. Submitted to International Journal of
Modern Physics
Lepton Flavor Violation: Constraints from exotic muon to electron conversion
The exotic neutrinoless nuclear conversion is studied within
the conventional extensions of the standard model as well as in the minimal
supersymmetric (SUSY) models with and without R-parity conservation. The
dependence of the conversion rates on the nucleon and nuclear
structure is consistently taken into account. Using our calculated transition
matrix elements and the available experimental data on the branching ratio
for Ti and Pb as well as the expected experimental
sensitivity for Al employed as a target in the planned at Brookhaven
conversion (MECO) experiment, we extract very severe constraints
for the flavor violation parameters. We especially emphasize on the constraints
resulting for SUSY R-parity violating parameters.Comment: 14 pages, 2 figures. Based on the Invited talk given by T.S. Kosmas
at the International Conference on Non-Accelerator New Physics(NANP'99),
Dubna, Russia, 199
Neutrinoless Double -Decay: Status and Future
A brief summary of the status of neutrino masses, mixing and oscillations is
presented. Neutrinoless double -decay is considered. Predictions for the
effective Majorana mass are reviewed. A possible test of the calculations of
nuclear matrix elements of the -decay is proposed.Comment: A report at the International conference ``Non-Accelerator New
Physics'' NANP05 Dubna, Russia, June 20-25, 200
Production of Triply Charmed Baryons in Annihilation
The total and differential cross sections for the production of triply
charmed baryons in annihilation are calculated at
the -boson pole.Comment: 13 pages, 2 figure
Neutrino Physics at the Turn of the Millenium
Recent solar & atmospheric nu-data strongly indicate need for physics beyond
the Standard Model. I review the ways of reconciling them in terms of 3-nu
oscillations. Though not implied by data, bi-maximal nu-mixing models emerge as
a possibility. SUSY with broken R-parity provides an attractive way to
incorporate it, opening the possibility of testing nu-anomalies at high- energy
colliders such as the LHC or at the upcoming long-baseline or nu- factory
experiments. Reconciling, in addition, the LSND hint requires a fourth, light
sterile neutrino, nus. The simplest are the most symmetric scenarios, in which
2 of the 4 neutrinos are maximally-mixed and lie at the LSND scale, while the
others are at the solar scale. The lightness of nus, the nearly maximal
atmospheric mixing, and the solar/atmospheric splittings all follow naturally
from the assumed lepton-number symmetry and its breaking. These basic schemes
can be distinguished at neutral-current-sensitive solar & atmospheric neutrino
experiments such as SNO. However underground experiments have not yet proven
neutrino masses, as there are many alternatives. For example flavour changing
interactions can play an important role in the explanation of solar and
contained atmospheric data and could be tested e.g through \mu \to e + \gamma,
\mu-e conversion in nuclei, unaccompanied by neutrino-less double beta decay.
Conversely, a short-lived numu might play a role in the explanation of the
atmospheric data. Finally, in the presence of a nus, a long-lived heavy nutau
could delay the time at which the matter and radiation contributions to the
energy density of the Universe become equal, reducing density fluctuations on
smaller scales, thus saving the standard CDM scenario, while the light nue,
numu and nus would explain the solar & atmospheric data.Comment: Invited talk at 2nd International Conference on Non-Accelerator New
Physics (NANP-99), Dubna, June 28 - July 3, 199
From AMANDA to IceCube
The first string of the neoteric high energy neutrino telescope IceCube
successfully began operating in January 2005. It is anticipated that upon
completion the new detector will vastly increase the sensitivity and extend the
reach of AMANDA to higher energies. A discussion of the IceCube's discovery
potential for extra-terrestrial neutrinos, together with the prospects of new
physics derived from the ongoing AMANDA research will be the focus of this
paper. Preliminary results of the first antarctic high energy neutrino
telescope AMANDA searching in the muon neutrino channel for localized and
diffuse excess of extra-terrestrial neutrinos will be reviewed using data
collected between 2000 and 2003. Neutrino flux limits obtained with the
all-flavor dedicated UHE and cascade analyses will be described. A first
neutrino spectrum above one TeV in agreement with atmospheric neutrino flux
expectations and no extra-terrestrial contribution will be presented, followed
by a discussion of a limit for neutralino CDM candidates annihilating in the
center of the Sun.Comment: 15 pages, 8 figures Invited talk contribution at 5th International
Conference on Non-accelerator New Physics (NANP 05), Dubna, Russia, 20-25 Jun
200
Antikaon angular distributions in the reaction near the threshold and the parity of the pentaquark
Within spectator model we study the reaction in the threshold energy region. We present the predictions for
the exclusive and inclusive antikaon angular distributions in the laboratory
system for this reaction calculated for two possible parity states of the
resonance at 1.5 and 1.75 GeV beam energies with and without
imposing the relevant kinematical cuts on those parts of the sampled phase
space where contribution from the main background sources associated with the
, production as well as with the
--rescattering in the final state, is expected to be dominant. We show
that under chosen kinematics these distributions are sensitive to the
parity and, therefore, can be used as a filter for the
determination of its parity.Comment: 18 pages, 8 figures; will be published in Phys.Atom.Nucl_4_200
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