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Information × Registration Number 0201U003733, 0199U004410 , R & D reports Title High-angular resolution observations of gravitational lenses popup.stage_title Head Dudinov V.M., Registration Date 17-04-2001 Organization Kharkov National University named after V.N. Karazin popup.description2 The subject of investigation is gravitational lens systems (GLS), in particular, images of remote quasars which are formed by gravitational fields of foreground galaxies in the case when the latters are located close to the line of sight between the quasar and the observer. The goal of the work is measuring the magnitudes and colours of individual lensed quasar components and investigation of their behaviour in time, the study of physical nature of these variations and obtaining new information about the spatial structure of quasars and near-nuclear regions of lensing galaxies. The methods of investigation are: CCD-photometry with the use of various image processing algorithms; numerical simulation of microlensing events. Photometric processing of a large number of CCD images of the Einstein Cross (Q2237+0305) gravitational lens system was fulfilled. The observations were made with the AZT-22 1,5-m telescope on the Maidanak mountain (Uzbekistan). The photometry of the lensed quasar components became a noticeable contribution into the existing international database on this object and allowed to prolong the historical lightcurves in the R spectral band. The most interesting results are those of the three-colour VRI photometry which permitted to follow a behaviour of the components' colours. It is argued that, in addition to prominent brightness variations of the components, noticeable variations of their colours take place in the Q2237+0305 GL system which contain an important information about the physical properties of both the quasar and the galaxy. Observations of other GL systems were also carried out. For four epochs observations of the SBS 1520+530, discovered in 1996, were fulfilled. The observations allowed to argue that the photometric activity of the system are rather low. A two-months monitoring in July-September 2000 did not revealed any noticeable short-period events which could be regarded as real. Product Description popup.authors popup.nrat_date 2020-04-02 Close