3,999 research outputs found
Orbital Ordering in ferromagnetic Lu2V2O7
We have observed the orbital ordering in the ferromagnetic Mott-insulator
Lu2V2O7 by the polarized neutron diffraction technique. The orbital ordering
pattern determined from the observed magnetic form factors can be explained in
terms of a linear combination of wave functions |yz>, |zx> and |xy>; |0> =
(1/3)^(1/2) |xy> + (1/3)^(1/2)|yz> + (1/3)^(1/2) |zx> which is proportional to
|(x + y + z)^2 - r^2>; where each orbital is extended toward the center-of-mass
of the V tetrahedron. We discuss the stability of the ferromagnetic Lu2V2O7,
using a Hubbard Hamiltonian with these three orbitals.Comment: 17pages. to be published in J. Phys. Soc. Jpn. 74 (2005
Analysis of Technical Efficiency of Small-Scale Rice Farmers in Indonesia
In this study, we analyzed the performance of small-scale rice farmers who used hand tractors in Jember Regency, Indonesia. Data were collected from 144 small-scale rice farmers in six districts through the use of a questionnaire in September 2015. The Data Envelopment AnalysisSlack-Based Model (DEA-SBM) was used to calculate the technical efficiency of small-scale rice farmers based on seven inputs and one output by determining Overall Technical Efficiency (OTE), Pure Technical Efficiency (PTE), and Scale Efficiency (SE). The results showed that out of 144 small-scale rice farmers, only nine farmers and 14 farmers were evaluated as strongly efficient and weakly efficient, respectively, while the rest were categorized as inefficient. The average values for OTE, PTE, and SE were 0.41, 0.63, and 0.61, respectively. The observed inefficiency was because of both poor input utilization (managerial inefficiency) and failure to operate at an optimal scale (scale inefficiency). Such analysis of technical efficiency can encourage small-scale rice farmers to enhance their performance and profitability
Energy Spectra of Quantum Turbulence: Large-scale Simulation and Modeling
In simulation of quantum turbulence within the Gross-Pitaevskii
equation we demonstrate that the large scale motions have a classical
Kolmogorov-1941 energy spectrum E(k) ~ k^{-5/3}, followed by an energy
accumulation with E(k) ~ const at k about the reciprocal mean intervortex
distance. This behavior was predicted by the L'vov-Nazarenko-Rudenko bottleneck
model of gradual eddy-wave crossover [J. Low Temp. Phys. 153, 140-161 (2008)],
further developed in the paper.Comment: (re)submitted to PRB: 5.5 pages, 4 figure
Multi-wavelength spectroscopic observation of EUV jet in AR 10960
We have studied the relationship between the velocity and temperature of a
solar EUV jet. The highly accelerated jet occurred in the active region NOAA
10960 on 2007 June 5. Multi-wavelength spectral observations with EIS/Hinode
allow us to investigate Doppler velocities at the wide temperature range. We
analyzed the three-dimensional angle of the jet from the stereoscopic analysis
with STEREO. Using this angle and Doppler velocity, we derived the true
velocity of the jet. As a result, we found that the cool jet observed with
\ion{He}{2} 256 \AA is accelerated to around which is over the upper limit of the chromospheric evaporation. The
velocities observed with the other lines are under the upper limit of the
chromospheric evaporation while most of the velocities of hot lines are higher
than that of cool lines. We interpret that the chromospheric evaporation and
magnetic acceleration occur simultaneously. A morphological interpretation of
this event based on the reconnection model is given by utilizing the
multi-instrumental observations.Comment: Accepted for publication in Ap
Comparison of Solar Fine Structure Observed Simultaneously in Ly-{\alpha} and Mg II h
The Chromospheric Lyman Alpha Spectropolarimeter (CLASP) observed the Sun in
H I Lyman-{\alpha} during a suborbital rocket flight on September 3, 2015. The
Interface Region Imaging Telescope (IRIS) coordinated with the CLASP
observations and recorded nearly simultaneous and co-spatial observations in
the Mg II h&k lines. The Mg II h and Ly-{\alpha} lines are important
transitions, energetically and diagnostically, in the chromosphere. The
canonical solar atmosphere model predicts that these lines form in close
proximity to each other and so we expect that the line profiles will exhibit
similar variability. In this analysis, we present these coordinated
observations and discuss how the two profiles compare over a region of quiet
sun at viewing angles that approach the limb. In addition to the observations,
we synthesize both line profiles using a 3D radiation-MHD simulation. In the
observations, we find that the peak width and the peak intensities are well
correlated between the lines. For the simulation, we do not find the same
relationship. We have attempted to mitigate the instrumental differences
between IRIS and CLASP and to reproduce the instrumental factors in the
synthetic profiles. The model indicates that formation heights of the lines
differ in a somewhat regular fashion related to magnetic geometry. This
variation explains to some degree the lack of correlation, observed and
synthesized, between Mg II and Ly-{\alpha}. Our analysis will aid in the
definition of future observatories that aim to link dynamics in the
chromosphere and transition region.Comment: Accepted by Ap
Coronal Temperature Diagnostic Capability of the Hinode/X-Ray Telescope Based on Self-Consistent Calibration
The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager
that observes the solar corona with unprecedentedly high angular resolution
(consistent with its 1" pixel size). XRT has nine X-ray analysis filters with
different temperature responses. One of the most significant scientific
features of this telescope is its capability of diagnosing coronal temperatures
from less than 1 MK to more than 10 MK, which has never been accomplished
before. To make full use of this capability, accurate calibration of the
coronal temperature response of XRT is indispensable and is presented in this
article. The effect of on-orbit contamination is also taken into account in the
calibration. On the basis of our calibration results, we review the
coronal-temperature-diagnostic capability of XRT
Avaliação de cultivares de alface crespa sob cultivo protegido no município de Iranduba/AM.
O objetivo deste trabalho foi avaliar o desempenho de cultivares de alface crespa sob cultivo protegido no município de Iranduba/AM.Suplemento. Trabalho apresentado no 52. Congresso Brasileiro de Olericultura, Salvador, 2012
Fermi Surface of Alpha-Uranium at Ambient Pressure
We have performed de Haas-van Alphen measurements of the Fermi surface of
alpha-uranium single crystals at ambient pressure within the alpha-3 charge
density wave (CDW) state from 0.020 K - 10 K and magnetic fields to 35 T using
torque magnetometry. The angular dependence of the resulting frequencies is
described. Effective masses were measured and the Dingle temperature was
determined to be 0.74 K +/- 0.04 K. The observation of quantum oscillations
within the alpha-3 CDW state gives new insight into the effect of the charge
density waves on the Fermi surface. In addition we observed no signature of
superconductivity in either transport or magnetization down to 0.020 K
indicating the possibility of a pressure-induced quantum critical point that
separates the superconducting dome from the normal CDW phase.Comment: 11 pages, 4 figures, 3 table
Realignment-enhanced coherent anti-Stokes Raman scattering (CARS) and three-dimensional imaging in anisotropic fluids
We apply coherent anti-Stokes Raman Scattering (CARS) microscopy to
characterize director structures in liquid crystals.Comment: 14 pages, 11 figure
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