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In 1982, the Central Laboratory for Geodesy (CLG) started a long-term study of the recent crustal movements in a local test area in a mobile region located southwards of Sofia.The recent geodynamic conditions and the deep structure of the Earth's crust in this region are described.Data on the local network of precise leveling are given-the scheme and characteristics of the loops, benchmarks and their monumentation. A first geodynamic analysis of the results of the first and third cycles of measurements is made, a map of the module of horizontal gradient of vertical velocity has been elaborated. The results obtained corroborate the reasons for the selection of this geodynamic test area. 相似文献
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R. Bachev D. Grupe S. Boeva E. Ovcharov A. Valcheva E. Semkov Ts. Georgiev L. C. Gallo 《Monthly notices of the Royal Astronomical Society》2009,399(2):750-761
We present the results from a monitoring campaign of the Narrow-Line Seyfert 1 galaxy PG 1211+143. The object was monitored with ground-based facilities ( UBVRI photometry; from 2007 February to July) and with Swift [X-ray photometry/spectroscopy and ultraviolet (UV)/optical photometry; between 2007 March and May]. We found PG 1211+143 in a historical low X-ray flux state at the beginning of the Swift monitoring campaign in 2007 March. It is seen from the light curves that while violently variable in X-rays, the quasar shows little variations in optical/UV bands. The X-ray spectrum in the low state is similar to other narrow-line Seyfert 1 galaxies during their low states and can be explained by a strong partial covering absorber or by X-ray reflection on to the disc. With the current data set, however, it is not possible to distinguish between both scenarios. The interband cross-correlation functions indicate a possible reprocessing of the X-rays into the longer wavelengths, consistent with the idea of a thin accretion disc, powering the quasar. The time lags between the X-ray and the optical/UV light curves, ranging from ∼2 to ∼18 d for the different wavebands, scale approximately as ∼λ4/3 , but appear to be somewhat larger than expected for this object, taking into account its accretion disc parameters. Possible implications for the location of the X-ray irradiating source are discussed. 相似文献
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Miladinova Irena Froitzheim Nikolaus Nagel Thorsten J. Janák Marian Georgiev Neven Fonseca Raúl O. C. Sandmann Sascha Münker Carsten 《International Journal of Earth Sciences》2018,107(6):2083-2099
International Journal of Earth Sciences - The Rhodopes in Bulgaria and Greece represent a nappe stack of high-grade units with polymetamorphic history. Constraining the time of metamorphism in... 相似文献
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The results of CCD photometric survey performed with the 90/180 cm Schmidt‐Cassegrain Telescope of the Nicolaus Copernicus University Astronomical Observatory in Piwnice (Poland) and the 70/172 cm Schmidt Telescope of the National Astronomical Observatory (NAO) at Rozhen (Bulgaria) of the field of the 1 Gyr old open cluster NGC 6939 are presented. Twenty two variable stars were detected, four of them previously known. Four eclipsing systems (3 detached and 1 contact binary) were found to be members of the cluster. Analysis of the brightness of the contact binary V20 strongly supports the distance to the cluster of 1.74 ± 0.20 kpc. The small population of contact binaries in NGC 6939 confirms also the relatively young age of the cluster. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Angelina Todorova Dimiter Syrakov Georgi Gadjhev Georgi Georgiev Kostadin G. Ganev Maria Prodanova Nikolai Miloshev Valery Spiridonov Andrej Bogatchev Kiril Slavov 《Earth Science Informatics》2010,3(4):259-282
Three Grid applications from the SEE-GRID-SCI Environmental VO are developed by the Bulgarian project team: Climate Change
Impact on Air Quality (CCIAQ); Multi-scale atmospheric composition modeling (MSACM); Modeling System for Emergency Response
to the Release of Harmful Substances in the Atmosphere (MSERRHSA). The three applications concern problems of significant
socio-economic significance. They are all dedicated to air pollution studies, but address different goals and so face different
problems and requirements. The applications are briefly presented in the paper. Examples of the different applications validations
are given. Some application results are shown and commented. 相似文献
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M. Mikolajewski T. Tomov M. Hajduk M. Cikala J. Osiwala C. Galan A. Zajczyk D. Kolev I. Iliev P. Marrese U. Munari T. Zwitter G. Galazutdinov F. Musaev A. Bondar L. Georgiev C. T. Bolton R. M. Blake W. Pych 《Astrophysics and Space Science》2005,296(1-4):451-455
High-resolution spectroscopy during the eclipse of EE Cep was obtained and presented for the first time. The star’s spectroscopic
behaviour can be roughly interpreted as a partial eclipse of the high luminosity Be primary and its emitting gaseous ring
by the semi-transparent gaseous envelope around an invisible, opaque secondary, most probably a dark disk.
This paper is based on spectroscopic observations from Asiago (Italy), DDO (Canada), Rozhen (Bulgaria), SPM (Mexico), Terskol
(Russia) and Torun (Poland) observatories. 相似文献
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