The Siberian Solar Radio Telescope: the current state of the instrument,observations, and data   总被引：2，自引：0，他引：2  

Grechnev  V.V.  Lesovoi  S.V.  Smolkov  G. Ya.  Krissinel  B.B.  Zandanov  V.G.  Altyntsev  A.T.  Kardapolova  N.N.  Sergeev  R.Y.  Uralov  A.M.  Maksimov  V.P.  Lubyshev  B.I. 《Solar physics》2003,216(1-2):239-272

The Siberian Solar Radio Telescope (SSRT) is one of the world's largest solar radio heliographs. It commenced operation in 1983, and since then has undergone several upgrades. The operating frequency of the SSRT is 5.7 GHz. Since 1992 the instrument has had the capability to make one-dimensional scans with a high time resolution of 56 ms and an angular resolution of 15 arc sec. Making one of these scans now takes 14 ms. In 1996 the capability was added to make full, two-dimensional images of the solar disk. The SSRT is now capable of obtaining images with an angular resolution of 21 arc sec every 2 min. In this paper we describe the main features and operation of the instrument, particularly emphasizing issues pertaining to the imaging process and factors limiting data quality. Some of the data processing and analysis techniques are discussed. We present examples of full-disk solar images of the quiet Sun, recorded near solar activity minimum, and images of specific structures: plages, coronal bright points, filaments and prominences, and coronal holes. We also present some observations of dynamic phenomena, such as eruptive prominences and solar flares, which illustrate the high-time-resolution observations that can be done with this instrument. We compare SSRT observations at 5.7 GHz, including computed `light curves', both morphologically and quantatively, with observations made in other spectral domains, such as 17 GHz radio images, Hα filtergrams and magnetograms, extreme-ultraviolet and X-ray observations, and dynamic radio spectra.  相似文献   

The radio brightness distribution along the solar limb observed on the Siberian Solar Radio Telescope     

B. B. Krissinel’ 《Astronomy Reports》2005,49(11):939-945

The radio brightness distribution at 5.2 cm has been obtained along the entire solar limb down to a level of 0.01 of brightness temperature at the disk center T ₀ ^c during the solar minimum. The measurements are based on strip scans from the Siberian Solar Radio Telescope. Data reduction included model fitting of an actual solar scan for each position angle. The maximum limb brightness, 1.37 T ₀ ^c , in the derived distribution is at equatorial direction, where the radio radius exceeds the photosphere radius by 7%. Toward the poles, the brightness peak and radio radius gradually decrease to 1.01 T ₀ ^c and 1.005 R₀. The derived two-dimensional brightness distribution was used to calculate radio radius as a function of position angle for several wavelengths from 4 to 31.6 cm. These dependences are consistent with RATAN-600 observations at position angles 0° and 25°.  相似文献   

Observations of bright coronal points at wavelengths of 5.2 and 1.76 cm     

V. P. Maksimov  D. V. Prosovetskii  B. B. Krissinel 《Astronomy Letters》2001,27(3):181-185

Based on two-dimensional solar images obtained with the Siberian Solar Radio Telescope and the Nobeyama Radio Heliograph and using YOHKOH soft X-ray images, we investigate bright coronal points. The principal microwave emission mechanism of these points is shown to be the thermal bremsstrahlung of an optically thin plasma. The fact that, in several cases, bright coronal points do not coincide at two wavelengths can be explained by imaging peculiarities of the Nobeyama Radio Heliograph rather than by physical factors.  相似文献   

Two-dimensional solar mapping at 5.2 cm with the Siberian Solar Radio Telescope     

C. E. Alissandrakis  B. I. Lubyshev  G. Ya. Smolkov  B. B. Krissinel  T. A. Treskov  V. G. Miller  N. N. Kardapolova 《Solar physics》1992,142(2):341-358

We present two-dimensional solar maps at 5.2 cm computed from one-dimensinal observations with the Siberian Solar Radio Telescope (SSRT), using Earth rotation aperture synthesis techniques. The resolution attained with the E-W branch of the instrument is 15 by 45 for a solar declination of about 23°. Maps during the period of June 8 to 13, 1988 clearly show the quiet-Sun background, sunspot and plage associated emission as well as compact sources above the neutral line in some active regions. We found that the latter disappear as the gradient of the longitudinal magnetic field decreases. We also detected emission associated with active regions behind the limb, apparently from unresolved loops, extending up to 40. The prospects of the SSRT, as a dedicated solar instrument, are discussed.  相似文献   

Finding of low-contrast formations in the solar corona using a low contrast method     

S. M. Kuznetsova  B. B. Krissinel  A. G. Obukhov  D. V. Prosovetsky  G. Ya. Smolkov 《Geomagnetism and Aeronomy》2009,49(7):850-855

Coronal holes, bright coronal points, filaments, and prominences are among the initial factors responsible for variability of the space weather conditions. Radioheliographic data on low-contrast formations contain valuable information necessary for studying conditions of origination, peculiarities of evolution, and prediction of solar-terrestrial relations. It is important to identify these formations on the solar disk when physical properties of coronal holes are revealed. The algorithm based on the Wiener-Tikhonov filter modification with controlled parameters and a high-frequency contrast filter was developed in order to isolate low-contrast formations in the solar corona brightness distributions obtained at a wavelength of 5.2 cm from the Siberian solar radio telescope observations. In this case low-contrast sources are isolated in two main stages: (1) HF noise smoothing based on an evolutionary filter with controlled parameters and (2) contrasting of sources using an HF filter. The evolutionary filter regularization parameters and the dimensions of an HF contrast filter mask are selected depending on the signal-to-noise ratio and dimensions of the studied region based on the results of preliminary data processing. The corresponding software has been developed in order to identify low-contrast objects on the Sun’s radio images using this method. The algorithm is used to isolate filaments and coronal holes and the results of this usage are presented in this work.  相似文献   

Millisecond-duration microwave burst observations with the SSRT fast data acquisition system   总被引：1，自引：0，他引：1  

A. T. Altyntsev  A. A. Dutov  V. V. Grechnev  S. K. Konovalov  B. B. Krissinel  E. G. Lisysian  V. G. Miller  Yu. M. Rosenkraukh  G. Ya. Smolkov  A. Magun 《Solar physics》1996,168(1):145-158

The hardware and software for the observation of millisecond bursts with the Siberian solar radio telescope (SSRT) at 5.2 cm is described. The multiprocessing computer and data acquisition system records 180 analog signals from the SSRT multichannel receiver every 7 milliseconds. The recorded information opens the opportunity to study the position, structure, and other characteristics of solar burst sources with high temporal and spatial resolution. Examples of the observations are presented and briefly discussed in order to illustrate the overall performance of the system.  相似文献