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991.
This paper deals with the organizational structure of ground-based receiving, processing, and dissemination of scientific information created by the Astrophysics Institute of the Scientific Research Nuclear University, Moscow Engineering Physics Institute. Hardware structure and software features are described. The principles are given for forming sets of control commands for scientific equipment (SE) devices, and statistics data are presented on the operation of facility during flight tests of the spacecraft (SC) in the course of one year.  相似文献   
992.
Radio stars are identified optically with bright stars located in the direction of the cluster A3487 (RA(J) = 11h31m58s, DEC(J) = −31°11’34".8) with an accuracy determined by the refraction of radio waves in the interstellar medium in this direction of the sky. Within an area of 1 sq. degree, 60% of the strong radio sources with P > 0.004 Jy are identified with stars brighter than 10 m.  相似文献   
993.
The solar wind plasma exhibits many features of the solar surface passed on to the interplanetary medium as temporal variations due to the solar rotation. The yearly average values of solar wind velocity, and geomagnetic index A p during 1965–1999 were found to exhibit long period evolution. They were found to peak around the declining phase of each solar cycle. While the solar wind velocity peaks around the second half of the declining phase, the IMF field strength increases around the first half of the declining phase of each solar cycle. The power spectrum of these parameters shows peaks around 37-day, 30-day, 27-day, 13.5-day, 9-day, and 7-day periods. The temporal evolution of the power spectrum of the solar wind plasma parameters and the geomagnetic activity index A p are also studied in detail and presented with the help of contour graphs. These studies indicate that the strength of the quasi-periodicities in the interplanetary medium evolves with time.  相似文献   
994.
We compare and combine likelihood functions of the cosmological parameters Ωm, h and σ 8, from peculiar velocities, cosmic microwave background (CMB) and type Ia supernovae. These three data sets directly probe the mass in the Universe, without the need to relate the galaxy distribution to the underlying mass via a 'biasing' relation. We include the recent results from the CMB experiments BOOMERANG and MAXIMA-1. Our analysis assumes a flat Λ cold dark matter (ΛCDM) cosmology with a scale-invariant adiabatic initial power spectrum and baryonic fraction as inferred from big-bang nucleosynthesis. We find that all three data sets agree well, overlapping significantly at the 2 σ level. This therefore justifies a joint analysis, in which we find a joint best-fitting point and 95 per cent confidence limits of     (0.17,0.39),     (0.64,0.86) and     (0.98,1.37). In terms of the natural parameter combinations for these data     (0.40,0.73),     (0.16,0.27). Also for the best-fitting point,     and the age of the Universe is 13.2 Gyr.  相似文献   
995.
Izmailov  I. S.  Shakht  N. A.  Polyakov  E. V.  Gorshanov  D. L.  Pogodin  M. A. 《Astrophysics》2021,64(2):160-171
Astrophysics - This paper is a continuation of our earlier work devoted to determining the orbit and mass of the star 61 Cyg and the changes in the photometric characteristics of its components....  相似文献   
996.
Solar System Research - The ionization-type cosmic dust detector METEOR-L is being developed for the lunar orbiter Luna-26 and is designed to study the distribution of meteoric bodies in space by...  相似文献   
997.
Solar System Research - The device is being developed for the TERMO-LR experiment on the Luna-27 lunar lander; it is intended for contact geophysical measurements of various properties of the lunar...  相似文献   
998.
Astronomy Letters - We present the first results of our program of optical observations for galaxy clusters from the Lockman Hole X-ray survey with the eROSITA telescope onboard the SRG space...  相似文献   
999.
Astronomy Letters - Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG...  相似文献   
1000.
The trajectories of plasma-sheet protons are computed numerically in magnetic-field models which simulate the neutral-sheet-type configuration observed in experiments. No electric field is included, in contrast with the reconnection theory. Entering the neutral sheet and then exiting from it, the particle performs an ordered displacement across the tail. A continuous interchange between the neutral and plasma sheets will give rise to an electric current which may be responsible for the observed magnetic-field configuration. An estimate of this current is made from the tension balance requirement, showing that a substantial anisotropy of the plasma-sheet pressure is necessary to maintain the steady state. It is shown that the neutral sheet itself can be a source of such an anisotropy, due to the non-adiabatic behaviour of protons. Other anisotropy origins are discussed briefly.  相似文献   
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