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1.
V. M. Tereshchenko 《Astronomy Reports》2002,46(3):224-232
We have obtained spectral energy distributions for 41 7m–8m stars near the celestial equator (δ=±3°). The λλ3100–7600 Å spectral range is studied with a spectral resolution of 50 Å. The relative rms error in the visible is 1–2%, increasing to 3–5% towards the edges of the wavelength interval studied. All stars are referenced to a single standard, the circumpolar star HD 221525. The synthetic colors of common stars are compared with those observed in four photometric systems: U BV, W BV R, uvby, and that of the TYCHO catalog. The program stars are recommended as secondary spectrophotometric standards. 相似文献
2.
A. A. Zhamaletdinov A. N. Shevtsov E. P. Velikhov A. A. Skorokhodov V. E. Kolesnikov T. G. Korotkova P. A. Ryazantsev B. V. Efimov V. V. Kolobov M. B. Barannik P. I. Prokopchuk V. N. Selivanov Yu. A. Kopytenko E. A. Kopytenko V. S. Ismagilov M. S. Petrishchev P. A. Sergushin P. E. Tereshchenko B. V. Samsonov M. A. Birulya M. Yu. Smirnov T. Korja Yu. M. Yampolski A. V. Koloskov N. A. Baru S. V. Poljakov A. V. Shchennikov G. I. Druzhin W. Jozwiak J. Reda Yu. G. Shchors 《Izvestiya Atmospheric and Oceanic Physics》2015,51(8):826-857
3.
Oceanology - The article is devoted to studing of the features of sedimentation on the bottom of the northwestern shelf and western deep-water area of the Black Sea based on an analysis of our own... 相似文献
4.
A new method of determining the anisotropy parameters of small-scale irregularities in the ionospheric F region is presented and experimental results are shown. The method is based on observations of amplitude fluctuations of radio waves transmitted by satellites flying above the F region. In practice, Russian navigational satellites are used and both the amplitude and the phase of the signal is measured on the ground level. The method determines both the field-aligned anisotropy and the field-perpendicular anisotropy and orientation of the spatial spectrum of the irregularities, assuming that the contours of constant power have an elliptic shape. A possibility of applying the method to amplitude tomography is also discussed. Using a chain of receivers on the ground level, one could locate the regions of small-scale irregularities as well as determine their relative intensities. Then the large-scale background structures could be mapped simultaneously by means of ordinary ray tomography using the phase observations, and therefore the relations of small-scale and large-scale structures could be investigated. 相似文献
5.
E. D. Tereshchenko M. O. Kozlova O. V. Evstafiev B. Z. Khudukon T. Nygrén M. Rietveld A. Brekke 《Annales Geophysicae》2000,18(9):1197-1209
Results on heating the ionospheric F region above Tromsø, Norway are presented. The ionosphere was monitored by satellite tomography and amplitude scintillation methods as well as the EISCAT incoherent scatter radar. No effect of heating was observed in the daytime. In the evening and in the pre-midnight sector, noticeable tilts of the F region were observed during heating periods. The tilts overlapped the heating cone, where the electron density decreased and irregularities exceeding 10 km in size appeared. Between the heating periods the F layer was restored to its horizontal shape. The anisotropic parameters of small-scale irregularities with scale lengths of hundreds of metres were also determined. It was found that the perpendicular anisotropy points in the direction of F region plasma flow. In some cases the results can be explained by assuming that the small-scale irregularities were generated within the heating cone and drifted out of the heating region where they were subsequently observed. 相似文献
6.
E. D. Tereshchenko B. Z. Khudukon M. O. Kozlova O. V. Evstafiev T. Nygrén M. T. Rietveld A. Brekke 《Annales Geophysicae》2000,18(8):918-926
Results are shown from an experimental campaign where satellite scintillation was observed at three sites at high latitudes and, simultaneously, the F region plasma flow was measured by the nearby EISCAT incoherent scatter radar. The anisotropy parameters of field-aligned irregularities are determined from amplitude scintillation using a method based on the variance of the relative logarithmic amplitude. The orientation of the anisotropy in a plane perpendicular to the geomagnetic field is compared with the direction of F region plasma flow. The results indicate that in most cases a good agreement between the two directions is obtained. 相似文献
7.
On the basis of the ion chemistry theoretical model, the impact of a powerful solar flare on variations in the ion composition and electron density in the D region of the polar ionosphere is considered. Good agreemnt between the model profiles of the electron density N e (h) and the experimental data obtained during the flare by the partial reflection method is found. It is shown that the decrease in the effective recombination coefficient observed during disturbances is explained by the depletion of the relative content of the rapidly recombining complex ion clusters. 相似文献
8.
I. A. Tereshchenko V. G. Shevchenko Yu. N. Krugly 《Kinematics and Physics of Celestial Bodies》2010,26(2):89-93
We investigate the photometric system consisting of the AZT-8 telescope BVRI filters, and IMG 1024S CCD-camera. The coefficients
of the transformation from the instrumental values of magnitudes and color indexes to the standard Johnson-Cousins system
for the BVRI bands are derived. 相似文献
9.
T. Nygren M. Markkanen M. Lehtinen E. D. Tereshchenko B. Z. Khudukon O. V. Evstafiev P. Pollari 《Annales Geophysicae》1997,14(12):1422-1428
In November 1995 a campaign of satellite radiotomography supported by the EISCAT incoherent scatter radar and several other instruments was arranged in Scandinavia. A chain of four satellite receivers extending from the north of Norway to the south of Finland was installed approximately along a geomagnetic meridian. The receivers carried out difference Doppler measurements using signals from satellites flying along the chain. The EISCAT UHF radar was simultaneously operational with its beam swinging either in geomagnetic or in geographic meridional plane. With this experimental set-up latitudinal scans of F-region electron density are obtained both from the radar observations and by tomographic inversion of the phase observations given by the difference Doppler experiment. This paper shows the first results of the campaign and compares the electron densities given by the two methods. 相似文献
10.
I. N. Glushneva A. V. Kharitonov I. B. Voloshina A. I. Zakharov L. N. Knyazeva V. M. Tereshchenko 《Astrophysics and Space Science》1989,152(2):313-317
TheSpectrophotometric Catalogue of the Sternberg State Astronomical Institute contains 875 stars; 8 of them are standards.TheCatalogue of the Fessenkov Astrophysical Institute consists of 1123 stars. The data on the spectral energy distribution for about a half of these stars are published.A comparison of energy distribution data for 473 common stars in the range 3200–7600 Å was made. Calibration of Alpha Lyr from Hayes (1985) was used for all the stars of both catalogues.In difference of the previous publications the comparison includes much more stars and energy distribution data were corrected where necessary. The agreement between the corrected data is better than in the case of the earlier comparison. Reductional factors due to the instrumental effects were taken into account for 275 stars from theSternberg Institute Catalogue. These factors are in the limits 1.01–1.04 and their mean value is 1.03.The reductional factors for the stars from theFessenkov Institute Catalague are much larger: 1.06–1.12 with the mean 1.06–1.07. In this case the reduction factors were taken into account for all the stars of the catalogue except the brightest ones withV<2.0.The values of the differences between spectral energy distribution data for common stars in dependence of magnitude, spectral type, and wavelength are presented. 相似文献