690 research outputs found
Calibration of the 6302/6301 Stokes V line ratio in terms of the 5250/5247 ratio
Four decades ago the Stokes V line ratio in the Fe I 5247.06 and 5250.22
{\AA} lines was introduced as a powerful means of exploring the intrinsic field
strengths at sub-pixel scales, which led to the discovery that most of the
photospheric flux is in intermittent kG form. The "green" 5247-5250 line pair
is unique because it allows the magnetic-field effects to be isolated from the
thermodynamic effects. No other line pair with this property has since been
identified. In recent years much of the magnetic-field diagnostics has been
based on the "red" Fe I 6301.5 and 6302.5 {\AA} line pair, since it was chosen
in the design of the Hinode space observatory. Although thermodynamic effects
severely contaminate the magnetic-field signatures for this line ratio, it is
still possible to use it to extract information on intrinsic magnetic fields,
but only after it has been "renormalized", since otherwise it produces
fictitious, superstrong fields everywhere. In the present work we explore the
joint behavior of these two line ratios to determine how the "contaminated" red
line ratio can be translated into the corresponding green line ratio, which
then allows for a direct interpretation in terms of intrinsic magnetic fields.
Our observations are mainly based on recordings with the ZIMPOL-3
spectro-polarimeter at IRSOL in Locarno, Switzerland, complemented by data from
the STOP telescope at the Sayan solar observatory (Irkutsk, Russia). The IRSOL
observations are unique by allowing both the green and red line pairs to be
recorded simultaneously on the same CCD sensor. We show how the line ratios
depend on both the measured flux densities and on the heliocentric distance
(the \mu\ value on the solar disk), and finally derive the calibration function
that enables the red line ratio to be translated to the green ratio for each
\mu\ value
Gauge theory solitons on noncommutative cylinder
We generalize to noncommutative cylinder the solution generation technique,
originally suggested for gauge theories on noncommutative plane. For this
purpose we construct partial isometry operators and complete set of orthogonal
projectors in the algebra of the cylinder, and an isomorphism between the free
module and its direct sum with the Fock module on the cylinder. We construct
explicitly the gauge theory soliton and evaluate the spectrum of perturbations
about this soliton.Comment: References added; to appear in Theor.Math.Phy
Spectral Inversion of Multi-Line Full-Disk Observations of Quiet Sun Magnetic Fields
Spectral inversion codes are powerful tools to analyze spectropolarimetric
observations, and they provide important diagnostics of solar magnetic fields.
Inversion codes differ by numerical procedures, approximations of the
atmospheric model, and description of radiative transfer. Stokes Inversion
based on Response functions (SIR) is an implementation widely used by the solar
physics community. It allows to work with different atmospheric components,
where gradients of different physical parameters are possible, e.g., magnetic
field strength and velocities. The spectropolarimetric full-disk observations
were carried out with the Stokesmeter of the Solar Telescope for Operative
Predictions (STOP) at the Sayan Observatory on 3 February 2009, when neither an
active region nor any other extended flux concentration was present on the Sun.
In this study of quiet Sun magnetic fields, we apply the SIR code
simultaneously to 15 spectral lines. A tendency is found that weaker magnetic
field strengths occur closer to the limb. We explain this finding by the fact
that close to the limb, we are more sensitive to higher altitudes in an
expanding flux tube, where the field strength should be smaller since the
magnetic flux is conserved with height. Typically, the inversions deliver two
populations of magnetic elements: (1) high magnetic field strengths (1500-2000
G) and high temperatures (5500-6500 K) and (2) weak magnetic fields (50-150 G)
and low temperatures (5000-5300 K).Comment: 10 pages, 6 figures, accepted for Solar Physic
Differential Calculus on -Deformed Light-Cone
We propose the ``short'' version of q-deformed differential calculus on the
light-cone using twistor representation. The commutation relations between
coordinates and momenta are obtained. The quasi-classical limit introduced
gives an exact shape of the off-shell shifting.Comment: 11 pages, Standard LaTeX 2.0
Magnetic anisotropy in strained manganite films and bicrystal junctions
Transport and magnetic properties of LSMO manganite thin films and bicrystal
junctions were investigated. Manganite films were epitaxially grown on STO,
LAO, NGO and LSAT substrates and their magnetic anisotropy were determined by
two techniques of magnetic resonance spectroscopy. Compare with cubic
substrates a small (about 0.3 persentage), the anisotropy of the orthorhombic
NGO substrate leads to a uniaxial anisotropy of the magnetic properties of the
films in the plane of the substrate. Samples with different tilt of
crystallographic basal planes of manganite as well as bicrystal junctions with
rotation of the crystallographic axes (RB - junction) and with tilting of basal
planes (TB - junction) were investigated. It was found that on vicinal NGO
substrates the value of magnetic anisotropy could be varied by changing the
substrate inclination angle from 0 to 25 degrees. Measurement of magnetic
anisotropy of manganite bicrystal junction demonstrated the presence of two
ferromagnetically ordered spin subsystems for both types of bicrystal
boundaries RB and TB. The magnitude of the magnetoresistance for TB - junctions
increased with decreasing temperature and with the misorientation angle even
misorientation of easy axes in the parts of junction does not change. Analysis
of the voltage dependencies of bicrystal junction conductivity show that the
low value of the magnetoresistance for the LSMO bicrystal junctions can be
caused by two scattering mechanisms with the spin- flip of spin - polarized
carriers due to the strong electron - electron interactions in a disordered
layer at the bicrystal boundary at low temperatures and the spin-flip by anti
ferromagnetic magnons at high temperatures.Comment: 26 pages, 10 figure
On the Hopf algebras generated by the Yang-Baxter R-matrices
We reformulate the method recently proposed for constructing quasitriangular
Hopf algebras of the quantum-double type from the R-matrices obeying the
Yang-Baxter equations. Underlying algebraic structures of the method are
elucidated and an illustration of its facilities is given. The latter produces
an example of a new quasitriangular Hopf algebra. The corresponding universal
R-matrix is presented as a formal power series.Comment: 10 page
The technology of creation of the standard base for socio-economic dimensions
© Medwell Journals, 2016.Practice education standards for assessing and comparing (comparing/contrasting) heterogeneous properties of controlled processes of socio-economic spheres. Design technique and technology to create a reference framework for processes in socio-economic sphere and on this basis to apply for measuring operations scientific methods of metrology. In this researchers methods of imitating and semantic modeling in a complex with methods of the economical and statistical analysis are used. Possibility of creation of the expert system reproducing technical and operational properties of natural market metrology, formation of general estimated function and a comparable measure of productivity for a set of diverse and multidirectional indicators is discussed. The model of creation of reference base for private indicators providing an integrated rating assessment of a condition of various organizational structures and processes is developed. The conclusion is that in terms of multidirectional indicators the most viable scheme of management of organizational systems is the formation of the reference base, the formation of normative-evaluative, the synthesis of multidimensional processes to one-dimensionality of a single criterion
Bicovariant Differential Geometry of the Quantum Group
There are only two quantum group structures on the space of two by two
unimodular matrices, these are the and the [9-13] quantum
groups. One can not construct a differential geometry on , which at
the same time is bicovariant, has three generators, and satisfies the Liebnitz
rule. We show that such a differential geometry exists for the quantum group
and derive all of its properties
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