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1.
Astronomy Reports - Methodological studies of spectral characteristics and statistical analysis of flicker noise are presented on the example of two data samples (2016–2017) on the X-ray nova... 相似文献
2.
We consider the detection of cosmic strings using observations of the anisotropy of the Cosmic Microwave Background. Several methods for detecting cosmic strings are analyzed, using a threshold filter and expansion in orthogonal Haar functions. Computer simulation provides estimates of the noise present in experiments aimed at detection of cosmic strings. Attempts to detect cosmic strings were carried out using the full-sky ILC map obtained as a result of the WMAP space mission. A list of cosmic string candidates has been compiled using the Haar function method. 相似文献
3.
I.?Yu.?Vlasov O.?S.?Sazhina V.?N.?Sementsov M.?V.?SazhinEmail author 《Astronomy Reports》2015,59(6):525-541
Binary stars are considered as possible sources of monochromatic gravitational waves. The amplitude of corrections to the metric generated by such sources is discussed. Three systems that have amplitudes for stresses of the metric exceeding 10?20 are identified (V1182 Aql, V3903 Sgr, and DH Cep). 相似文献
4.
The spectrum of the random angular velocities of ICRF sources is analyzed. This spectrum is calculated assuming that the apparent
angular velocities of the sources are random and uncorrelated, and that the directions of the motions of each source are uniformly
distributed over a circle. The amplitudes of the vector spherical harmonics display a white-noise spectrum. Published observational
data are considered, and preliminary conclusions are drawn about the nature of the observed dipole and quadrupole harmonics
in the spectrum of angular velocities. 相似文献
5.
N. P. Grushinsky Natasha B. Sazhina D. A. Brown 《Australian Journal of Earth Sciences》2013,60(3):183-199
A map of the geoid in Australia and surrounding oceanic areas has been produced on a scale of 1:5M. There are two variants, both of which employ Bouguer anomalies for the land areas. For the ocean areas in the first variant, anomalies have been obtained as the difference between the observed and theoretical values of gravity at sea level. In the second variant, a correction has been introduced to reduce the density of the water layer to the average density of the Earth's crust. The height of the geoid in Australia is calculated in the same way. The effect of distant zones has been allowed for in accordance with the data of Kozai (1967) and Köhnlein (1967), and a high precision for the geoid height for Australia has been obtained. Discrepancies between the new data and the observations of Mather (1969) amount to + 2 m for the regions investigated and ± 4 m for the entire continent. Coordinates have also been obtained for the centre of the Australian ellipsoid relative to the centre of the Earth's mass. 相似文献
6.
V.A. Sergeev E.M. Sazhina N.A. Tsyganenko J.Å. Lundblad F. Søraas 《Planetary and Space Science》1983,31(10):1147-1155
Characteristics of the nightside isotropic precipitation of energetic protons during a period of 4 quiet days has been studied using data from the ESRO 1A satellite. The observed features of the equatorward precipitation boundary (its thickness, energy dependence, dynamics, dependence of its latitudinal position on the magnetic field at the geosynchronous orbit, etc.) were found to be in good agreement with calculations based on recent magnetospheric magnetic field models. We argue that the mechanism of non-adiabatic pitchangle scattering in the equatorial current sheet is a dominant source of isotropic precipitation of energetic protons observed in the nightside auroral zone. Observations of the isotropic precipitation boundary can be used for monitoring the changes in the magnetotail current intensity. 相似文献
7.
The plans to launch the RadioAstron space system in the near future and the realization the planned record resolution of 1
microarcsecond will require the precise determination of the satellite orbit. Suitable models for the satellite motion must
be provided, including taking into account relativistic effects. We have obtained equations making it possible to construct
time scales on board the satellite and at the observation point with accuracy up to 1 ps, as well as relativistic relations
for measuring the distance to the satellite using one-way and two-way techniques and the Doppler effect, with a relative uncertainty
of 10−15, necessary for achieving the precision required for the RadioAstron mission. 相似文献
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The effect of weak microlensing on the apparent velocities of extragalactic sources is considered; in particular, the apparent
motions of sources from the ICRF list are discussed. We expect from two to seven cases of apparent motions of extragalactic
sources due to weak microlensing by stars or dark bodies in our Galaxy to be detected over the next 30 years. 相似文献
10.
An approximate formula is derived for the refractive index of a whistler-mode wave propagating in a hot anisotropic plasma with wave normal angle close to the resonance cone angle (θR). Approximations used during the derivation are generally satisfied for magnetospheric conditions. It is pointed out that the derived formula can be considered to be complementary to the corresponding formula for quasilongitudinal whistler-mode propagation in a hot anisotropic plasma which was derived by Sazhin and Sazhina (1982). The limits of applicability of a cold plasma model when determining the height of generation of saucer emissions and V-shaped hiss are discussed. 相似文献