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1.
Within the framework of a five-year campaign of coordinated multifrequency observations of the 3 Tauri star RU Lupi, we present results obtained in X-ray, UV, optical, and IR spectral regions. In five cases, simultaneous data from UV to IR were collected. Data analysis shows a large variability at different wavelengths both in the continuum and lines, stronger in the UV and weaker in the IR. Correlations among variations in the UV and optical continua have been found. Moreover flare-like events (FLEs), probably due to strong activity in the surface layers of the star and burst phenomena on large scale, were detected. No forbidden coronal lines were detected in UV and optical regions with IUE and ESO 1.4m CAT telescope, respectively. This means either the used instruments have not enough sensitivity to detect the predicted forbidden lines, or the low X-ray detected intensity — with ASTRON satellite (2–25 keV) — is due to the absorption of the X-rays in the circumstellar envelope. In this paper we will discuss these results within the framework of the current models.Based on observations with IUE satellite (VILSPA) and ESO telescopes.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain 相似文献
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Rakhimov I. R. Vishnevskiy A. V. Saveliev D. E. Salikhov D. N. Vladimirov A. G. 《Geology of Ore Deposits》2021,63(4):341-367
Geology of Ore Deposits - For the first time, from the standpoint of magmatism and subsequent hydrothermal–metasomatic alteration, sulfide and platinum-metal mineral assemblages of rocks of... 相似文献
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A. M. Finkelstein A. V. Ipatov Yu. N. Gnedin D. V. Ivanov M. A. Kharinov I. A. Rakhimov 《Astronomy Letters》2004,30(6):368-375
We present the radio observations of the afterglow from the intense cosmic gamma-ray burst GRB 030329 performed with the radio telescopes of the Institute of Applied Astronomy, Russian Academy of Sciences, at the Svetloe (λ=3.5 cm) and Zelenchuk (λ=6 cm) Observatories. The difference between the fluxes measured in two different polarization modes suggests the existence of a circular polarization in the radio afterglow from GRB 030329. However, since the measurement errors of the fluxes with different circular polarizations are large, we cannot draw a firm conclusion about its detection; we can only set an upper limit on its value. An analysis of the possible generation mechanisms for the circular polarization of the relativistic jet suggests that there is a helical magnetic field in the jet. The existence of significant flux densities at various wavelengths during a long (≥10 days) period leads us to conclude that the hydrodynamic evolution of the relativistic bow shock takes place in the stellar wind, not in the interstellar medium. We have estimated the total GRB energy (E=1051 erg) (under the assumption of isotropic radiation) and the plasma density of the stellar wind from the presupernova (n=3 cm?3). The magnetic-field strength in the relativistic jet can be estimated as B≈100 G. 相似文献
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A. M. Finkelstein E. A. Skurikhina I. F. Surkis A. V. Ipatov I. A. Rakhimov S. G. Smolentsev 《Astronomy Letters》2008,34(1):59-68
Regular high-precision determinations of the Earth’s orientation parameters (EOPs) on the Quasar VLBI Network were begun in
August 2006. The observations are performed within the framework of two national programs: daily sessions at three observatories
of the Network to determine all five EOPs (the RU-E program) and 8-h sessions on the Zelenchukskaya-Badary and Svetloe-Badary
baselines to determine the Universal Time (the RU-U program). The observations from August 2006 through May 2007 are analyzed.
The rms deviations of the EOP values obtained in the RU-E program from the IERS C04 series are 1.1 mas for X
p and Y
p, 37 μs for UT1-UTC, and 0.7 and 0.6 mas for X
c and Y
c, respectively. These results closely match the prospective requirements of GLONASS. The rms deviations of the Universal Times
obtained in the RU-U program from the IERS C04 series are 146 μs. We consider the immediate prospects for improving the accuracy
of EOP determinations in daily sessions and for implementing the e-VLBI mode for an online determination of the Universal
Time.
Original Russian Text ? A.M. Finkelstein, E.A. Skurikhina, I.F. Surkis, A.V. Ipatov, I.A. Rakhimov, S.G. Smolentsev, 2008,
published in Pis’ma v Astronomicheskiĭ Zhurnal, 2008, Vol. 34, No. 1, pp. 66–76. 相似文献
6.
Institute of Astrophysics, Academy of Sciences of Tadzhikistan. Shternberg State Astronomical Institute. Odessa Observatory. Translated from Astrofizika, Vol. 36, No. 1, pp. 55–60, January–February, 1993. 相似文献
7.
Yu. N. Golubchikov K. K. Rakhimov A. D. Sobyanin V. S. Tikunov 《Geography and Natural Resources》2012,33(3):258-261
The interests of Russia, as a Eurasian state, must be geared not only toward the West, East and North but also toward the South. The transport capabilities of Trans-Sib (Trans-Siberian Railway) will be enhanced dramatically once it is connected with the Indian Ocean via a network of meridional railways. In particular, this would provide an entry for grain exports into countries of Central and South Asia. Some elements of the Indo-Siberian arterial railway are traceable even in the existing network of the former Soviet railways in Central Asia. It is suggested that the project be started from the Chui-Fergana Trans-Kyrgyz Railway. 相似文献
8.
I. V. Gosachinskij S. A. Grenkov A. V. Ipatov I. A. Rakhimov 《Astrophysical Bulletin》2016,71(3):330-342
We report the results of three-year long observations of OH masers at 1665 MHz in the W3(OH) source carried out with the 32-m antenna of Svetloe Radio Astronomical Observatory.We found that the strongest activity during the period from December 2011 through March 2012 was exhibited by the region at radial velocity ?46.2km s?1. The region showed no activity in the ensuing time. The most striking outburst was the event that occurred on January 23, 2013 at UT 03:27. At that time the flux of the region increased by a factor of seven in 90 s, and then decreased down to the initial level. Such a time scale yields the upper estimate of 0.18 AU (2.7 × 1012 cm) for the linear size of the maser dot. In 2013–2014 intensity variations were found the ?47.6 and ?45.1km s?1 components with time scales on the order of 10 hours and anticorrelated behavior of the left- and right-hand polarization fluxes. This is the first time that such phenomena have been found in the behavior of OH maser emission, and they cannot be explained by any existing models of maser variability. 相似文献
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V. P. Ivanov I. A. Rakhimov S. G. Smolentsev K. S. Stankevich A. M. Finkelstein 《Astronomy Letters》2004,30(4):240-246
We measured the flux densities of the radio source 3C 58, which was identified with the remnant of SN 1181, in April–May 2003 relative to the spectrum of the standard source 3C 295 at fourf requencies in the range 1550 to 8450 MHz using the RTF-32 radio telescope at the Svetloe Observatory of the Institute of Applied Astronomy (Russian Academy of Sciences). We found significant nonstationary frequency-dependent flux-density variations in 3C 58 and variations in its instantaneous spectrum. We established that these variations occurred between 1986 and 1998. Based on data for the instantaneous spectra, we show that the break in the spectrum of 3C 58 results from prolonged energy losses by relativistic electrons through synchrotron radiation that took place in a nebula with an age of 5400 yr, equal to the age of the pulsar PSR J0205+6449. SN 1181 is shown to have exploded without the birth of a pulsar, which is characteristic of type-I supernovae. The shock acceleration of relativistic electrons after the explosion may be responsible for the observed nonstantionarity of the flux densities. The long-term evolution of the radio spectrum for the nebula 3C 58 and the nonstationary flux-density variations due to the explosion of SN 1181 are reconciled in terms of a model of an evolved binary system. 相似文献