7,834 research outputs found
Detection of Exotic Massive Hadrons in Ultra High Energy Cosmic Ray Telescopes
We investigate the detection of exotic massive strongly interacting hadrons
(uhecrons) in ultra high energy cosmic ray telescopes. The conclusion is that
experiments such as the Pierre Auger Observatory have the potential to detect
these particles. It is shown that uhecron showers have clear distinctive
features when compared to proton and nuclear showers. The simulation of uhecron
air showers, and its detection and reconstruction by fluorescence telescopes is
described. We determine basic cuts in observables that will separate uhecrons
from the cosmic ray bulk, assuming this is composed by protons. If these are
composed by heavier nucleus the separation will be much improved. We also
discuss photon induced showers. The complementarity between uhecron detection
in accelerator experiments is discussed.Comment: 9 page 9 figure
Influencia do tipo de estaca e de alguns reguladores de crescimento no enraizamento e desenvolvimento de estacas de figueira (Ficus carica L.).
O presente trabalho teve como objetivo estudar as influencias da posicao da estaca no ramo (apical, mediana e basal) e dos acidos naftalenoacetico (ANA) e indolbutirico (IBA), isolados e combinados, sobre o enraizamento e desenvolvimento da parte aerea de estacas de figueira. O delineamento experimental foi de blocos ao acaso com parcelas subdivididas. As estacas tinham 30 cm de comprimento, sendo que 5 cm da base foram imersas nas solucoes correspondentes durante 1 minuto, sendo depois tratadas com fungicida Captan a 25% para posterior plantio. As mudas mais vigorosas originaram-se das estacas de base dos ramos. Todos os tratamentos com auxinas proporcionaram um melhor enraizamento, sendo que a combinacao 250 ppm IBA + 250 ppm ANA foi mais eficiente na formacao das raizes, acarretando tambem um aumento de peso da parte aerea
Anisotropic Lifshitz Point at
We present the critical exponents , and
for an -axial Lifshitz point at second order in an expansion.
We introduced a constraint involving the loop momenta along the -dimensional
subspace in order to perform two- and three-loop integrals. The results are
valid in the range . The case corresponds to the usual
Ising-like critical behavior.Comment: 10 pages, Revte
Spin Dynamics in the Two-Dimensional Spin 1/2 Heisenberg Antiferromagnet
We present low-temperature dynamic properties of the quantum two-dimensional
antiferromagnetic Heisenberg model with spin S=1/2. The calculation of the
dynamic correlation function is performed by combining a projection operator
formalism and the modified spin-wave theory (MSW), which gives a gap in the
dispersion relation for finite temperatures. The so calculated dynamic
correlation function shows a double peak structure.We also obtain the spin-wave
damping and compare our results to experimental data and to theoretical results
obtained by other authors using different approaches.Comment: 17 pages, 5 figures and 1 tabl
Avaliação de genótipos de uvas apirenas no tropico semi-árido do Brasil.
Este trabalho teve como objetivo avaliar o comportamento de uvas apirenas de forma a caracterizá-las na região do Trópico Semi-Árido do Brasil
Poda e área das folhas em plantas de castanheira-do-brasil (bertholletia excelsa humb.& bonpl., lecythidaceae).
A Novel Low-Cost Sensor Prototype for Nocturia Monitoring in Older People
Indexación: Scopus.This work was supported in part by CORFO - CENS 16CTTS-66390 through the National Center on Health Information Systems, in part by the National Commission for Scientific and Technological Research (CONICYT) through the program STIC-AMSUD 17STIC-03: ‘‘e-MONITOR âĂŞ Chronic Disease: Ambient Assisted Living and vital teleMONOTORing for e-health,’’ FONDEF ID16I10449 ‘‘Sistema inteligente para la gestión y análisis de la dotación de camas en la red asistencial del sector público,’’ and MEC80170097 ‘‘Red de colaboración científica entre universidades nacionales e internacionales para la estructuración del doctorado y magister en informática médica en la Universidad de Valparaíso.’’ The work of V. H. C. de Albuquerque was supported by the Brazilian National Council for Research and Development (CNPq) under Grant #304315/2017-6.Nocturia is frequently defined as the necessity to get out of bed at least one time during the night to urinate, with each of these episodes being preceded and continued by sleep. Several studies suggest that an increase of nocturia is seen with the onset of age, occurring in around 70% of adults over the age of 70. Its appearance is associated with detrimental quality of life for those who present nocturia, since it leads to daytime sleepiness, cognitive dysfunction, among others. Currently, a voiding diary is necessary for nocturia assessment; these are prone to bias due to their inherent subjectivity. In this paper, we present the design of a low-cost device that automatically detects micturition events. The device obtained 73% in sensibility and 81% in specificity; these results show that systems such as the proposed one can be a valuable tool for the medical team when evaluating nocturia. © 2013 IEEE.https://ieeexplore.ieee.org/document/845445
Neutrino Telescopes as a Direct Probe of Supersymmetry Breaking
We consider supersymmetric models where the scale of supersymmetry breaking
lies between 5 GeV and 5 GeV. In this class of
theories, which includes models of gauge mediated supersymmetry breaking, the
lightest supersymmetric particle is the gravitino. The next to lightest
supersymmetric particle is typically a long lived charged slepton with a
lifetime between a microsecond and a second, depending on its mass. Collisions
of high energy neutrinos with nucleons in the earth can result in the
production of a pair of these sleptons. Their very high boost means they
typically decay outside the earth. We investigate the production of these
particles by the diffuse flux of high energy neutrinos, and the potential for
their observation in large ice or water Cerenkov detectors. The relatively
small cross-section for the production of supersymmetric particles is partially
compensated for by the very long range of heavy particles. The signal in the
detector consists of two parallel charged tracks emerging from the earth about
100 meters apart, with very little background. A detailed calculation using the
Waxman-Bahcall limit on the neutrino flux and realistic spectra shows that
km experiments could see as many as 4 events a year. We conclude that
neutrino telescopes will complement collider searches in the determination of
the supersymmetry breaking scale, and may even give the first evidence for
supersymmetry at the weak scale.Comment: 4 pages, 3 figure
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