http://dspace.nbuv.gov.ua:80/handle/123456789/114706 2026-04-17T09:44:45Z http://dspace.nbuv.gov.ua:80/handle/123456789/119662 Tests of commercial colour CMOS cameras for astronomical applications Pokhvala, S.M.; Reshetnyk, V.M.; Zhilyaev, B.E. We present some results of testing commercial colour CMOS cameras for astronomical applications. Colour CMOS sensors allow to perform photometry in three filters simultaneously that gives a great advantage compared with monochrome CCD detectors. The Bayer BGR colour system realized in colour CMOS sensors is close to the astronomical Johnson BVR system. The basic camera characteristics: read noise (e⁻/pix), thermal noise (e⁻/pix/sec) and electronic gain (e⁻/ADU) for the commercial digital camera Canon 5D MarkIII are presented. We give the same characteristics for the scientific high performance cooled CCD camera system ALTA E47. Comparing results for tests of Canon 5D MarkIII and CCD ALTA E47 show that present-day commercial colour CMOS cameras can seriously compete with the scientific CCD cameras in deep astronomical imaging. 2013-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119661 On the comparison of fundamental numerical ephemerides Tkachuk, V.V.; Choliy, V.Ya. We present the results of our comparison of three main numerical ephemerides (DELE, INPOP, EPM) for the determination of precision and errors of their dynamical coordinate systems. It was shown that all of them have comparable levels of precision, however the EPM demonstrates an unusual shift of the coordinate origin. Systematic errors were estimated as well, and mutual shifts of coordinate centres were found. 2013-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119660 Electromagnetic radiation of superconducting cosmic strings Rogozin, D.A.; Zadorozhna, L.V. Cosmic strings are relics of the early Universe which can be formed during the phase transitions of fields with spontaneously broken symmetry in the early Universe. Their existence finds support in modern superstrings theories, both in compactification models and in theories with extended additional dimensions. Strings can hold currents, effectively become electrically superconducting wires of astrophysical dimensions. Superconducting cosmic strings can serve as powerful sources of non-thermal radiation in wide energy range. Mechanisms of radiation are synchrotron, synchrotron self-Compton and inverse-Compton on CMB photons radiation of electrons accelerated by bow shock wave, created by magnetosphere of relativistically moving string in intergalactic medium (IGM). Expected fluxes of radiation from the shocked plasma around superconducting cosmic strings are calculated for strings with various tensions and for different cases of their location. Possibilities of strings detection by existing facilities are estimated. 2013-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/119650 Explosive evolution of galaxies at high redshifts due to minor mergers Kats, A.V.; Kontorovich, V.M. In the case of minor mergers analytical solutions of kinetic Smoluchowski equation with a source that corresponds to separation of galaxies from the general expansion of the universe have been found. The solutions describe the explosive evolution of galaxy mass function in the presence of the dark matter. The evolution of power-law asymptote at large redshifts is discussed. 2013-01-01T00:00:00Z