The magnetic field in the local interstellar medium (ISM) provides a key indicator of the galactic environment of the Sun and influences the shape of the heliosphere. In this paper, we extend the ...analysis by utilizing weighted fits to the position angles and by including new observations acquired for this study. We find that the local ISMF is pointed toward the galactic coordinates scriptl, b = 47degrees + or - 20degrees, 25degrees + or - 20degrees. This direction is close to the direction of the ISMF that shapes the heliosphere, scriptl, b = 33degrees + or - 4degrees, 55degrees + or - 4degrees, as traced by the center of the "Ribbon" of energetic neutral atoms discovered by the Interstellar Boundary Explorer (IBEX) mission. The peculiar geometrical relation found earlier between the cosmic microwave background dipole moment, the heliosphere nose, and the ISMF direction is supported by this study.
Abstract
In this paper, the problem of creating homogeneous composites with on carbon nanotubes is described. To control the quality of the manufactured composites, a system of terahertz ...visualization of material inhomogeneity using a continuous radiation source is used. An increase in the homogeneity of the composite based on multi-walled carbon nanotubes with an increase in the time of ultrasonic processing during polymerization is noted. The advantages of THz imaging in comparison with optical microscopy are shown.
Aims. The intensity profiles of the C2 Swan bands in cool DQ white dwarfs cannot be adequately fitted with models that otherwise succesfully reproduce spectral features of the molecule CH in these ...stars. Initial modelling showed that a two-component atmosphere in the style of a spot might be able to solve the problem. Methods. We photometrically observed the two cool DQ white dwarfs GJ1117 and EGGR78 to search for variability caused by stellar spots. Results. We have not found any such variability, but we estimate the effects of hypothetical spots on lightcurves. We also estimate detection probabilities for spots in different configurations. Alternative explanations of the problem are needed and briefly discussed.
Methods of reconstructing holographic images of objects made of the composite based on carbon fibermodified acrylonitrile-butadiene styrene and a thin electrically conductive film are presented. ...Holograms are obtained in the axial scheme when the collimating lens is placed on the source axis. Results of comparison of the calculated frequency response of the model transmission coefficient with measurements on an experimental setup are presented.
The process
e
+
e
-
→
n
n
¯
is studied in the experiment at the VEPP-2000
e
+
e
-
collider with the SND detector. The technique of the time measurements in the multichannel NaI(Tl) electromagnetic ...calorimeter is used to select
n
n
¯
events. The value of the measured cross section in the center-of-mass energy range from 1.894 to 2 GeV varies from 0.5 to 0.35 nb. The effective neutron timelike form factor is derived from the measured cross section and compared with the proton form factor. The ratio of the neutron electric and magnetic form factors is obtained from the analysis of the antineutron polar angle distribution and found to be consistent with unity.
Abstract
In paper results of research of metamaterial surface based on split-ring resonators obtained by photolithography are presented. Numerical simulation of electromagnetic response of the ...created structure are shown. Experimental researches of the transmission coefficient using quasi-optical methods of continuous and time-domain spectroscopy in the frequency range from 34 to 200 GHz were carried out. Area of broadband screening in the EHF range has been found.
Aims. We investigate the structure of the O-type binary system HD48099 by measuring linear polarization that arises due to light scattering process. High-precison polarimetry provides independent ...estimates of the orbital parameters and gives important information on the properties of the system. Methods. Linear polarization measurements of HD48099 in the B, V and R passbands with the high-precision Dipol-2 polarimeter have been carried out. The data have been obtained with the 60 cm KVA (Observatory Roque de los Muchachos, La Palma, Spain) and T60 (Haleakala, Hawaii, USA) remotely controlled telescopes during 31 observing nights. Polarimetry in the optical wavelengths has been complemented by observations in the X-rays with the Swift space observatory. Results. Optical polarimetry revealed small intrinsic polarization in HD48099 with ~0.1% peak to peak variation over the orbital period of 3.08 d. The variability pattern is typical for binary systems, showing strong second harmonic of the orbital period. We apply our model code for the electron scattering in the circumstellar matter to put constraints on the system geometry. A good model fit is obtained for scattering of light on a cloud produced by the colliding stellar winds. The geometry of the cloud, with a broad distribution of scattering particles away from the orbital plane, helps in constraining the (low) orbital inclination. We derive from the polarization data the inclination i= 17degrees + or - 2degrees and the longitude of the ascending node Omega = 82degrees + or - 1degrees of the binary orbit. The available X-ray data provide additional evidence for the existence of the colliding stellar winds in the system. Another possible source of the polarized light could be scattering from the stellar photospheres. The models with circumstellar envelopes, or matter confined to the orbital plane, do not provide good constraints on the low inclination, better than i< or = 27degrees, as is already suggested by the absence of eclipses.
The process
e
+
e
-
→
η
η
γ
is studied in the center-of-mass energy range 1.17–2.00 GeV using data with an integrated luminosity of 201 pb
-
1
collected by the SND detector at the VEPP-2000
e
+
e
-
...collider. The
e
+
e
-
→
η
η
γ
cross section is measured for the first time. It is shown that the dominant mechanism of this reaction is the transition through the
ϕ
η
intermediate state. Our result on the
e
+
e
-
→
η
η
γ
cross section is consistent with the
e
+
e
-
→
ϕ
η
measurement in the
ϕ
→
K
+
K
-
mode. The search for radiative processes contributing to the
e
+
e
-
→
η
η
γ
cross section is performed, and no significant signal is observed.
ABSTRACT A recently discovered filament of polarized starlight that traces a coherent magnetic field is shown to have several properties that are consistent with an origin in the outer heliosheath of ...the heliosphere: (1) the magnetic field that provides the best fit to the polarization position angles is directed toward = 357 3, b = 17 0 ( 11 2); this direction is within 6 7 11 2 of the observed upwind direction of the flow of interstellar neutral helium gas through the heliosphere. (2) The magnetic field is ordered; the component of the variation of the polarization position angles that can be attributed to magnetic turbulence is 9 6. (3) The axis of the elongated filament can be approximated by a line that defines an angle of 80° 14° with the plane that is formed by the interstellar magnetic field (ISMF) vector and the vector of the inflowing neutral gas (the plane). We propose that this polarization feature arises from aligned interstellar dust grains in the outer heliosheath where the interstellar plasma and magnetic field are deflected around the heliosphere. This interpretation suggests that the polarization is seen where stream lines of the flow and the draped ISMF lines are approximately parallel to each other and perpendicular to the sightline. An ordered magnetic field is required so that grain alignment is not disrupted during the interaction. The filament location is consistent with dust plumes previously predicted to form around the heliosphere. The proposed outer heliosheath location of the polarizing grains can be tested with three-dimensional models that track torques on asymmetric dust grains as they propagate through the heliosheath plasma, and using these models to evaluate grain alignment and the asymmetric extinction of the grains.
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