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The time and energy resolutions of scintillation detectors based on gadolinium gallium garnet (Ce:GAGG) crystals produced via cooperation between the Kurchatov Institute, the Research Institute for Nuclear Problems of the Belarusian State University, and the Fomos Materials Co. (Moscow, Russia, http://newpiezo.com/company/) were measured in comparison with crystals produced by the C&A Corporation (Japan). The measurements were performed for γ rays with energies ranging from ~20 keV to ~2 MeV. R3998-100-02 photomultiplier tubes and ArrayB-3035-144P silicon photomultiplier (SiPM) arrays were used as photodetectors. The time and energy resolutions of the crystals from Fomos Materials were competitive with the crystals produced by leading world companies and, in particular, by the C&A Corporation, Japan. It was shown by the measurements of the intrinsic radiation background of the gadolinium gallium garnet crystals that the scintillators from Fomos Materials, in combination with SiPM arrays, had very good prospects for use in compact spectrometric detectors of γ rays and charged particles and, in particular, detectors designed for future space experiments. [ABSTRACT FROM AUTHOR]

The new stage of work on digitizing the astronomical plates of the Sternberg Astronomical Institute's collection and searching for new variable stars using the digitized photographic plates includes a considerable improvement of the automated search techniques for objects with variable brightnesses. In particular, the technique for taking into account the non-linear response of the photographic light detector has been improved. Applying the improved techniques to 182 digitized images of a 10° × 10° field centered at SA9, obtained from scanning photographic plates taken with the Sternberg Astronomical Institute 40-cm astrograph, has enabled the discover and study of 77 new variable stars (MDV 519-595). These include 3 Cepheids, 2 probable BY Draconis stars, 65 eclipsing binaries, 3RR Lyrae stars, 1 high-amplitude δ Scuti star (HADS), and 3 irregular variables. Special CCD observations have confirmed the presence of brightness variations in 7 of the 77 variables that were initially considered uncertain. [ABSTRACT FROM AUTHOR]