5,056 research outputs found
Soil moisture: Some fundamentals
A brief tutorial on soil moisture, as it applies to agriculture, is presented. Information was taken from books and papers considered freshman college level material, and is an attempt to briefly present the basic concept of soil moisture and a minimal understanding of how water interacts with soil
Interactions of Heavy Hadrons using Regge Phenomenology and the Quark Gluon String Model
The search for stable heavy exotic hadrons is a promising way to observe new
physics processes at collider experiments. The discovery potential for such
particles can be enhanced or suppressed by their interactions with detector
material. This paper describes a model for the interactions in matter of stable
hadrons containing an exotic quark of charges or
using Regge phenomenology and the Quark Gluon String Model. The influence of
such interactions on searches at the LHC is also discussed
Local Hadronic Calibration of Single Pion Data from the Combined ATLAS Testbeam of 2004
For the first time, the local hadronic calibration scheme has been applied to real data from the combined test beam of 2004. In this note, the performance of the weighting of the combined test beam data is shown in relation to Monte Carlo simulations. The performance of the local calibration scheme when applied to simulated jets in full ATLAS set-up has also been demonstrated, and compared with the current default jet calibration, the "global" method. The local hadronic calibration achieves a calorimeter linearity within 3%, and the linearities of simulation and test beam data after weighting are in agreement. The calibration improves the resolution of simulated test beam data for beam energies larger than 8 GeV, and energies larger than 20 GeV for the data. In addition, the local hadronic calibration is shown to be a stable method for compensating the calorimeter system of ATLAS
Tevatron-for-LHC Report: Preparations for Discoveries
This is the "TeV4LHC" report of the "Physics Landscapes" Working Group,
focused on facilitating the start-up of physics explorations at the LHC by
using the experience gained at the Tevatron. We present experimental and
theoretical results that can be employed to probe various scenarios for physics
beyond the Standard Model.Comment: 222 pp., additional contribution added, typos/layout correcte
An Updated Description of Heavy-Hadron Interactions in Geant-4
Exotic stable massive particles (SMP) are proposed in a number of scenarios
of physics beyond the Standard Model. It is important that LHC experiments are
able both to detect and extract the quantum numbers of any SMP with masses
around the TeV scale. To do this, an understanding of the interactions of SMPs
in matter is required. In this paper a Regge-based model of R-hadron scattering
is extended and implemented in Geant-4. In addition, the implications of
-hadron scattering for collider searches are discussed
Long-lived stops in MSSM scenarios with a neutralino LSP
This work investigates the possibility of a long-lived stop squark in
supersymmetric models with the neutralino as the lightest supersymmetric
particle (LSP). We study the implications of meta-stable stops on the sparticle
mass spectra and the dark matter density. We find that in order to obtain a
sufficiently long stop lifetime so as to be observable as a stable R-hadron at
an LHC experiment, we need to fine tune the mass degeneracy between the stop
and the LSP considerably. This increases the stop-neutralino coanihilation
cross section, leaving the neutralino relic density lower than what is expected
from the WMAP results for stop masses ~1.5 TeV/c^2. However, if such scenarios
are realised in nature we demonstrate that the long-lived stops will be
produced at the LHC and that stop-based R-hadrons with masses up to 1 TeV/c^2
can be detected after one year of running at design luminosity
A synthesis of ENSO effects on drylands in Australia, North America and South America
Fundamentally, El Niño Southern Oscillation (ENSO) is a climatic and oceanographic phenomenon, but it has profound effects on terrestrial ecosystems. Although the ecological effects of ENSO are becoming increasingly known from a wide range of terrestrial ecosystems (Holmgren et al., 2001), their impacts have been more intensively studied in arid and semiarid systems. In this brief communication, we summarize the main conclusions of a recent symposium on the effects of ENSO in these ecosystems, which was convened as part of the First Alexander von Humboldt International Conference on the El Niño Phenomenon and its Global Impact, in Guayaquil, Ecuador, from 16–20 May 2005. Participants in the symposium shared results and perspectives from research conducted in North and South America and Australia, regions where the ecological effects of ENSO have been studied in depth. Although the reports covered a wide array of organisms and ecological systems (Fig. 1), a recurring theme was the strong increase in rainfall associated with ENSO events in dry ecosystems (during the El Niño phase of the oscillation in the Americas and the La Niña phase in Australia). Because inter-annual variability in precipitation is such a strong determinant of productivity in arid and semiarid ecosystems, increased ENSO rainfall is crucial for plant recruitment, productivity and diversity in these ecosystems. Several long-term studies show that this pulse in primary productivity causes a subsequent increase in herbivores, followed by an increase in carnivores, with consequences for changes in ecosystem structure and functioning that can be quite complex
Agricultural soil moisture experiment: 1978 Colby (Kansas) data catalog and documentation
There are no author-identified significant results in this report
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