Porovnání výpočtu zásob vybraných slojí jižního pole Dolu Doubrava metodou UNESCO a geologických bloků

Import 20/04/2006Prezenční výpůjčkaVysoká škola báňská. Fakulta hornicko-geologická. Katedra (522) ložiskové a průzkumné geologi

Possible substellar companions in low-mass eclipsing binaries: GU Bootis and YY Geminorum

We present the next results of our long-term observational project to analyze the variations in the orbital periods of low-mass eclipsing binaries. About 70 new precise mid-eclipse times recorded with a CCD were obtained for two eclipsing binaries with short orbital periods: GU Boo (P = 0.​d49) and YY Gem (0.​d81). Observed-minus-calculated diagrams of the stars were analyzed using all reliable timings, and new parameters of the light-time effect were obtained. We derived for the first time or improved the short orbital periods of possible third bodies of 11 and 54 years for these low-mass binaries, respectively. We calculated that the minimum masses of the third components are close to 50 MJup, which corresponds to the mass of brown dwarfs. The multiplicity of these systems also plays an important role in the precise determination of their physical parameters

B.R.N.O. Contributions #38 Times of minima

This paper presents observations of eclipsing binaries acquired by members and cooperating observers of the Variable Star and Exoplanet Section of Czech Astronomical Society (B.R.N.O. observing project). Paper contains 3417 times of minima for 969 objects. It was obtained by 80 observers during 2011 – 2013 period. Some neglected southern eclipsing binaries and newly discovered stars by the observers of project B.R.N.O. are included in the list. New accurate ephemerides have been found for 447 binary systems. Time of primary minimum of long period variable eps Aur is presented as wellFil: Hoňková, K. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Juryšek, J. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Lehký, M. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Astronomical Society at Hradec Kralove; República ChecaFil: Šmelcer, L. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Valašské Meziříčí Observatory; República ChecaFil: Trnka, J. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. City Observatory Slaný; República ChecaFil: Colazo, C. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Estación Astrofísica Bosque Alegre; ArgentinaFil: Guzzo, P. Estación Astrofísica Bosque Alegre; ArgentinaFil: Mina, Federico Daniel. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Quinones, C. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Taormina, M. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Melia, R. Observatorio Remoto Bosque Alegre; ArgentinaFil: Schneiter, Ernesto Matías. Estación Astrofísica Bosque Alegre; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Scavuzzo, Alan Martin. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Marcionni, M. Estación Astrofísica Bosque Alegre; ArgentinaFil: Tapia, L. Estación Astrofísica Bosque Alegre; ArgentinaFil: Fasseta, G. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Suarez, N. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Vilášek, M. Observatory and Planetarium of Johann Palisa; República ChecaFil: Rozehnal, J.. Štefánik Observatory; República ChecaFil: Kalisch, T. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Lang, K.. Klokkerholm; DinamarcaFil: Gorková, S. ALTAN.Observatory; República ChecaFil: Novysedlák, R. Námestie sv. Martina; EslovaquiaFil: Salvaggio, F. Gruppo Astrofili Catanesi; ItaliaFil: Smyčka, T. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. City Observatory Slaný; República ChecaFil: Spurný, M. Nejdlova 16; República ChecaFil: Wikander, T. Ornäs Backyard; República ChecaFil: Mravik, J. Slobodana Jajića 16; República ChecaFil: Šuchaň, J. Kraskova 12; EslovaquiaFil: Čaloud, J.. V Dolině 211; República Chec

Instabilities in interacting binary stars

The types of instability in the interacting binary stars are reviewed. The project "Inter-Longitude Astronomy" is a series of smaller projects on concrete stars or groups of stars. It has no special funds, and is supported from resources and grants of participating organizations, when informal working groups are created. Totally we studied 1900+ variable stars of different types. The characteristic timescale is from seconds to decades and (extrapolating) even more. The monitoring of the first star of our sample AM Her was initiated by Prof. V.P. Tsesevich (1907-1983). Since more than 358 ADS papers were published. Some highlights of our photometric and photo-polarimetric monitoring and mathematical modelling of interacting binary stars of different types are presented: classical, asynchronous, intermediate polars and magnetic dwarf novae (DO Dra) with 25 timescales corresponding to different physical mechanisms and their combinations (part "Polar"); negative and positive superhumpers in nova-like and many dwarf novae stars ("Superhumper"); eclipsing "non-magnetic" cataclysmic variables; symbiotic systems ("Symbiosis"); super-soft sources (SSS, QR And); spotted (and not spotted) eclipsing variables with (and without) evidence for a current mass transfer ("Eclipser") with a special emphasis on systems with a direct impact of the stream into the gainer star's atmosphere, or V361 Lyr-type stars. Other parts of the ILA project are "Stellar Bell" (interesting pulsating variables of different types and periods - M, SR, RV Tau, RR Lyr, Delta Sct) and "Novice"(="New Variable") discoveries and classification with a subsequent monitoring for searching and studying possible multiple components of variability. Special mathematical methods have been developed to create a set of complementary software for statistically optimal modelling of variable stars of different types.Comment: Non-Stable Universe: Energetic Resources, Activity Phenomena and Evolutionary Processes, 19-23 September 2016, ed. Areg Mickaelian, Haik Harutyunian and Elena Nikoghosyan, Astronomical Society of the Pacific (ASP) Conference Series, 2017, in pres