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Information × Registration Number 0308U001660, 0107U000674 , R & D reports Title Astrophysical investigations and monitoring of the Sun, Jupiter and the Moon on data of earthbased and space observations popup.stage_title Моніторинг сонячної активності. Фотополяриметричні дослідження Місяця та Юпітера Head Korokhin Victor Valentinovich, Registration Date 15-02-2008 Organization Kharkov Natuional university named after V.N.Karazin popup.description2 Objects of the investigations are the solar corona and chromosphere, the lunar surface and Jovian atmosphere. Goal of the work is monitoring of solar activity, studying of physical properties of the solar corona and chromosphere, atmospheres and surfaces of planets. Methods of investigation are spectrometrical, photometrical and polarimetrical, using theoretical analysis of data, theoretical and digital modeling the processes of light scattering on planets surfaces and in atmospheres. The observations of coronal holes in center and wings of line НеІ l 1083 nm were carried out during 19 days on modernized spetroheliograph with matrix CCD in the project of IHY/UNBSSI Developing Nations Program. The patrol observations of solar Ha - chromosphere activity were carried out according to International Solar Service programs: 74 days of patrol, 4 flares, 2 DSD, 1 APR. The results have been sent to WCD-A (Boulder, USA) and have been printed in "Solar-Geophysical Data". Changing the existing refractor on reflector will allow the increasing of angular and time resolution and will provide the possibility of simultaneous observations in several spectral lines. The height distribution of absolute surface brightness of chromosphere in the D3 НеІ line I(h) has been obtained for one point of west limb on spectrums of eclipse of March 29, 2006. It was shown that I(h) has one maximum at the height ~2000 km which is less by absolute value than data from previous eclipses. It confirms our assumption that lower maximum at height distribution of helium is absent during solar activity minimum. The construction of 2D distribution of surface brightness along height and limb latitude has been started for the final conclusions. The temporal dependence of integral brightness of D3 line along solar limb has been obtained. The necessity of taking into account the atmospheric shimmers has been shown. The instrumentation and procedure of observation of the Sun edge scintillations have been developed. Measurements of root-mean-square value of amplitude of the scintillations have been carried out on the observation station of RIA KhNU. It was shown that minimum value of amplitude is s~0.5І, and in 70% cases the amplitude is sЈ1І. For the first time the observations of amplitude of the Sun edge scintillations have been carried out in eclipses day. This allowed estimating the reaction of atmosphere on rapid change of surface illuminance. The decrease of amplitude of the scintillations after passing of large cloud has been found. These observations have shown also, that the construction of observing hut has the large influencing on amplitude of scintillations of sun edge. The time dependences of the surface brightness for fragments of 10 AR were analyzed from the SPIRIT/CORONAS-F images taken during March 3 - 4, 2002 in the Mg XII 0.84 nm line with the sampling rate of 1 minute between the neighboring frames. A correlation between brightness variations of some pairs of AR fragments separated by distances of 10° - 106° has been found to be significant. Statistical characteristics of the bursts distribution in time have been investigated. The observed temporal inhomogeneity has been determined to be impossible if the random Poisson process was the case. The occurrence of magnetic loops between fragments of AR has been studied. It was revealed that the sympathetic bursts were observed in some pairs of AR fragments. The most probable time delays between the bursts in various AR have been evaluated. It was shown that velocity of propagation of the excitation connected by coronal loops is equal ~ 1700 km/s. The probable values of magnetic field strength are 55 - 340 Gs if the related sympathetic bursts are caused by propagation of magneto-hydrodynamic waves in the coronal loops. It is concluded that most of the quasi-synchronous events of March 3 - 4, 2002, were generated by simultaneous emergence of the new magnetic flows in the photosphere, which was conditional on the evolution of great equatorial coronal hole (CH). New polarimetric observations of Jupiter, which continues observational program started in 1981, have been carried out in 2007. Observations of 2007 at filter "B" (?eff =456 nm) and processing the observations obtained on mountain Majdanak (Uzbekistan) at 2006 (?eff =470 nm) give values of the north-south asymmetry of linear polarization degree: 0.03±0.72?% (2007) та 0.00 ±0.10?% (2006). Database of polarimetrical observations of the Moon in 2006 has been built. Laboratory studying of the instrument and processing of the first series of absolute photometry have been performed. Map of lunar reflectance at phase angle 27° has been obtained. A method for calibration of equigonal albedo maps has been developed. It uses Irvine-Lane's data of integral photometry, mean spectrum of the Moon and Akimov's catalogue. Mapping the parameters of the phase dependence of the lunar albedo has been carried out, using and functions. It is shown that the 3-parameters function is sufficient for approximation of phase curve of highlands at 8?…123? phase angles diapason. It is shown that maria demonstrate more complex behavior of the brightness phase dependence in contrast to highlands. It may be explained by lesser power of mesorelief for maria and, as consequence, by significant contribution of the albedo effects at large phase angles. An algorithm for computing the light scattering in multicomponent medium has been implemented using C++ programming language. It allows to perform calculations not only using PC but using computers with any architecture. New implementation has much better characteristics and thus allows to use it for calculations of light scattering in 2D and 3D media. Product Description popup.authors popup.nrat_date 2020-04-02 Close