9,221 research outputs found
Detecting transit signatures of exoplanetary rings using SOAP3.0
CONTEXT. It is theoretically possible for rings to have formed around
extrasolar planets in a similar way to that in which they formed around the
giant planets in our solar system. However, no such rings have been detected to
date.
AIMS: We aim to test the possibility of detecting rings around exoplanets by
investigating the photometric and spectroscopic ring signatures in
high-precision transit signals.
METHODS: The photometric and spectroscopic transit signals of a ringed planet
is expected to show deviations from that of a spherical planet. We used these
deviations to quantify the detectability of rings. We present SOAP3.0 which is
a numerical tool to simulate ringed planet transits and measure ring
detectability based on amplitudes of the residuals between the ringed planet
signal and best fit ringless model.
RESULTS: We find that it is possible to detect the photometric and
spectroscopic signature of near edge-on rings especially around planets with
high impact parameter. Time resolution 7 mins is required for the
photometric detection, while 15 mins is sufficient for the spectroscopic
detection. We also show that future instruments like CHEOPS and ESPRESSO, with
precisions that allow ring signatures to be well above their noise-level,
present good prospects for detecting rings.Comment: 13 pages, 16 figures, 2 tables , accepted for publication in A&
Light clusters and the pasta phase
The effects of including light clusters in nuclear matter at low densities
are investigated within four different parametrizations of relativistic models
at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase)
are described for neutral nuclear matter with fixed proton fractions. We
discuss the effect of the density dependence of the symmetry energy, the
temperature and the proton fraction on the non-homogeneous matter forming the
inner crust of proto-neutron stars. It is shown that the number of nucleons in
the clusters, the cluster proton fraction and the sizes of the Wigner Seitz
cell and of the cluster are very sensitive to the density dependence of the
symmetry energy.Comment: 14 pages, 14 figures; Accepted for publication in Phys. Rev.
Distributed crowd-based annotation of soccer games using mobile devices
Soccer is one of the most loved sports in the world. Millions of people either follow the sport or are actually involved in its practice. Soccer also moves huge financial amounts every year and therefore teams always thrive to be better than the competition. New technologies have become a common place both in the preparation of the games and on the analysis of the games after they are concluded. In this paper, the authors will present a developed system, based on the usage of distributed mobile devices, that will enable the annotation of soccer matches, either in real time or after the matched is concluded (through the observation of other media). The capture of relevant events in the game can be used to better analyse the game and the performance of individual players fostering improvements and better decisions in the future. The application is implemented in the Android platform so that it can be easily installed by typical soccer fans empowering them as match annotators. This crowd of annotators, although not experts, can collectively provide a robust and rich annotation for soccer matches.info:eu-repo/semantics/publishedVersio
Uso da ressonância magnética nuclear de baixo campo na determinação rápida do teor de umidade em madeiras.
Neste trabalho é apresentada uma recomendação da utilização da técnica de ressonância magnética nuclear (RMN) de baixo campo como método alternativo na determinação rápida da umidade em madeiras. Este método utiliza o espectrômetro de RMN desenvolvido pela Embrapa Instrumentação Agropecuária e transferido para a Empresa GIL Equipamentos Especiais.bitstream/CNPDIA/9437/1/RT12_99.pd
Global aspects of gravitomagnetism
We consider global properties of gravitomagnetism by investigating the
gravitomagnetic field of a rotating cosmic string. We show that although the
gravitomagnetic field produced by such a configuration of matter vanishes
locally, it can be detected globally. In this context we discuss the
gravitational analogue of the Aharonov-Bohm effect.Comment: 10 pages - Typeset using REVTE
Manejo e controle das principais pragas da cultura do arroz irrigado na região do baixo São Francisco.
bitstream/item/64533/1/CPATC-DOCUMENTOS-70-MANEJO-E-CONTROLE-DAS-PRINCIPAIS-PRAGAS-DA-CULTURA-DO-ARROZ-IRRIGADO-NA-REGIA.pd
Demonstration of Imaging Flow Diagnostics Using Rayleigh Scattering in Langley 0.3-Meter Transonic Cryogenic Tunnel
The feasibility of using the Rayleigh scattering technique for molecular density imaging of the free-stream flow field in the Langley 0.3-Meter Transonic Cryogenic Tunnel has been experimentally demonstrated. The Rayleigh scattering was viewed with a near-backward geometry with a frequency-doubled output from a diode-pumped CW Nd:YAG laser and an intensified charge-coupled device camera. Measurements performed in the range of free-stream densities from 3 x 10(exp 25) to 24 x 10(exp 25) molecules/cu m indicate that the observed relative Rayleigh signal levels are approximately linear with flow field density. The absolute signal levels agree (within approx. 30 percent) with the expected signal levels computed based on the well-known quantities of flow field density, Rayleigh scattering cross section for N2, solid angle of collection, transmission of the optics, and the independently calibrated camera sensitivity. These results show that the flow field in this facility is primarily molecular (i.e., not contaminated by clusters) and that Rayleigh scattering is a viable technique for quantitative nonintrusive diagnostics in this facility
Liquid crystal phase and waterlike anomalies in a core-softened shoulder-dumbbells system
Using molecular dynamics we investigate the thermodynamics, dynamics and
structure of 250 diatomic molecules interacting by a core-softened potential.
This system exhibits thermodynamics, dynamics and structural anomalies: a
maximum in density-temperature plane at constante pressure and maximum and
minimum points in the diffusivity and translational order parameter against
density at constant temperature. Starting with very dense systems and
decreasing density the mobility at low temperatures first increases, reach a
maximum, then decreases, reach a minimum and finally increases. In the
pressure-temperature phase diagram the line of maximum translational order
parameter is located outside the line of diffusivity extrema that is enclosing
the temperature of maximum density line. We compare our results with the
monomeric system showing that the anisotropy due to the dumbbell leads to a
much larger solid phase and to the appearance of a liquid crystal phase. the
double ranged thermodynamic and dynamic anomalies.Comment: 14 pages, 5 figure
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