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Yu. A. Kovalev V. I. Vasil’kov M. V. Popov V. A. Soglasnov P. A. Voitsik M. M. Lisakov A. M. Kut’kin N. Ya. Nikolaev N. A. Nizhel’skii G. V. Zhekanis P. G. Tsybulev 《Cosmic Research》2014,52(5):393-402
The results of a large number of the antenna radiometric measurements at bands of 92, 18, 6.2, 1.35, and 1.7-1.2 cm are presented by the data of the standard telemetry system of the Spektr-R spacecraft. Both special sessions of calibration object observations in the mode of a single space radio telescope (SRT) operation and numerous observations of researched sources in the mode of the ground-space interferometer were used. The obtained results agree with the first results of Kardashev et al. (2013), i.e., within 10–15% at bands of 92, 18, and 6.2 cm and 20–25% at the band of 1.35 cm. In the main, the measurements for the eight subbands at wavelengths of 1.7-1.2 cm indicate a monotonic increase in the spectral system equivalent flux density (SEFD) of noise radiation with a frequency consistent with the calculated estimates for the discussed model. The sensitivity of the ground-space interferometer for the five subbands at wavelengths from 1.35 to 1.7 cm can be higher by a factor of 1.5, and for the three subbands from 1.35 to 1.2 cm lower by a factor of 1.5 than at the band of 1.35 cm. The SRT contribution to the interferometer sensitivity proportional to the square root of SEFD is close to the design one at the bands of 92 and 18 cm and decreases the design sensitivity approximately by a factor of 1.5 and 2 at the bands of 6.2 and 1.35 cm, respectively. These differences of implemented values from the design ones were not significantly affected the scientific program implementation. 相似文献
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G. A. Zherebtsov V. A. Kovalenko S. I. Molodykh O. A. Rubtsova L. A. Vasil’eva 《Cosmic Research》2008,46(4):358-366
We present the mechanism and the concept of a model of the solar activity impact on thermobaric and climatic characteristics of the troposphere. Both are based on the idea of parametric action. The results of analysis are presented concerning specific features and regularities of changes in temperature regime of the troposphere in the period of variable helio-and geophysical activity, as well as long-term variations of temperature and heat content of the troposphere. The influence of changes in circulation in the atmosphere and ocean on processes in the system atmosphere-ocean-cryosphere is considered: thermohaline circulation of the oceans and energy exchange between the atmosphere and ocean. The revealed regularities find their complete explanation within the context of a model and mechanism of solar activity impact on climatic characteristics of the troposphere that were suggested previously by the authors. 相似文献
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The paper regards two-impulse transfer from a low parking orbit into a circular orbit with the altitude less than 36 000 km, while the inclination correction is carried out with each maneuver. An approximate formula is proposed capable of evaluating analytically the optimal value of the first correction of inclination; the corresponding accuracy data are given. Examples are provided to show the operational efficiency of an optimal non-coplanar transfer of the type II with injections of satellites into various target orbits from Russian launch sites with due account of the available launch azimuths. 相似文献
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Calorimeters play an important role in cosmic-ray physics and, in particular, in experiments, which are carried out in the
atmosphere with balloons and on satellites in space. This paper presents a method of energy measurement for protons (at energy
higher than 20 GeV) with the help of a thin discrete calorimeter (using as an example the position-sensitive silicon-tungsten
calorimeter of the PAMELA experiment) developed based on the data of simulation by the Monte-Carlo method and on the results
of test experiment at an accelerator in charged particle beams. The method is based on measurement of the total released energy
and on the criterion of event selection, which characterizes the beginning of particle cascade development in the calorimeter.
The influence of insertion of additional parameters on the energy resolution obtained with the help of this method is also
studied. 相似文献
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