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Fokin, A. B.; Tutukov, A. V.
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In order to study the problem of mass loss by WolfRayet stars, we carried out numerical simulations of nonlinear pulsations of these objects. Although our computations do not show direct dynamical mass loss, qualitative estimates show that certain as yet unobserved pulsations could in principle, create conditions facilitating mass outflows from WolfRayet stars.
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By
Denisov, M. M.
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1 Citations
A mathematical model is constructed for the motion of an electromagnetic pulse used in laser ranging of the OZIRIS spacecraft. A formula is derived for the calculation of corrections to the distance of the spacecraft associated with the noninertial motion of the laser station and the influence of the gravitational field of the Earth on the laser pulses. It is shown that these corrections must be taken into account when carrying out precision laser ranging of the spacecraft with the goal of distance determination to within 20 cm or better.
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By
Molodenskiĭ, M. M.; Starkova, L. I.
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1 Citations
The nature of structures detected recently on the Sun in soft X rays by I.F. Nikulin (Sternberg Astronomical Institute) and called by him “partings” is discussed. It is shown that these structures are signreversal lines for the normal component of the curvature vector of the magnetic lines. Equations describing these lines are derived and models of the corresponding fields calculated.
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By
Bajkova, A. T.; Pushkarev, A. B.
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Maps of the radio source 3C 120 obtained from VLBA+ observations at 8.4 GHz at five epochs in January–September 2002 are presented. The images were reconstructed using the maximum entropy method and the Pulkovo VLBImager software package for VLBI mapping. Apparent superluminal motions of the brightest jet knots have been estimated. The speeds of jet knots decreases with distance from the core, changing from (5.40±0.48)c to (2.00±0.48)c over 10 mas (where c is the speed of light) for a Hubble constant of 65 km s^{−1} Mpc^{−1}. This can be explained by interaction of the jet with the medium through which it propagates.
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By
Vereshchagin, S. V.; Reva, V. G.; Chupina, N. V.
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The Hyades Cluster is used to analyze details of the ADdiagram method developed in our earlier works and applied to the corona of the Ursa Major stream. Hipparcos data are used to analyze the kinematics of the Hyades Cluster and determine its apex. Evidence for rotation of the cluster is presented.
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By
Tarbeeva, S. M.; Semikoz, V. B.; Sokoloff, D. D.
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We study the behavior of largescale magnetic fields in the early Universe influenced by an instability associated with breaking of mirror symmetry in weak interactions. It is shown that the magnetic field, whose present scale reaches about 500 m, which is negligible for galactic sizes, increases considerably if we correctly take into account the dynamics of the Universe. We conclude that this magnetic field is unlikely to provide the seed field for galactic dynamos, nearly independent of the particular instability considered.
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By
Eselevich, M. V.; Eselevich, V. G.
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6 Citations
The first experimental evidence for a perturbed zone that is likely filled with fast magnetoacoustic oscillations and precedes a coronal mass ejection is presented. When the speed of the coronal mass ejection exceeds the Alfven speed, an outwardmoving discontinuity of the plasma density is observed in front of the perturbed zone, on scales comparable to the meanfree path for protonproton collisions. This suggests that this discontinuity should be interpreted as a collisional shock at distances of R < 30 R_{⊙} (where R_{⊙} is the solar radius).
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By
Strokov, V. N.
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15 Citations
We show that the hydrodynamical and field approaches in the theory of cosmological scalar perturbations are equivalent for a single medium. We also give relations between the notations introduced by Lukash, Bardeen, Bardeen et al., and Chibisov and Mukhanov.
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By
Poltorak, S. G.; Fridman, A. M.
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5 Citations
A method is proposed for the determination of the position and inclination angles of the plane of a spiral galaxy based on the assumption that every spiral arm is a monotonic function of the radius and/or the azimuthal angle. This method may yield more accurate results than the more commonly employed isophote method, which is fraught with various drawbacks. The use of the new method is illustrated by applying it to a sample of 43 objects, and the results agree well with data from other sources.
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