Results 1 to 10 of about 2,451 (48)

Symbiotic Stars: Observations Confront Theory

Open Astronomy, 2012
In this paper, I present and discuss some recent observational results which may have important implications for our understanding of late phases of binary evolution.
Mikołajewska J.
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LONG-TERM ACTIVITY CHANGES OF UV PISOIUM

Odessa Astronomical Publications, 2017
UV Psc has been observed since 1976 at the Ankara and Ege University Observatories. Mean light curves in B and V colours obtained using the maxima levels of observed light curves of the system.
V. Keskin, Z. Tunca, C. Ibanoglu, Z. Aslan, S. O. Selam, Z. Muyesseroglu   +5 more
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SBS 0802+529: A New Variable Star from the Second Byurakan Survey

Open Astronomy, 2012
A new emission line star was discovered on the plates of the Second Byurakan Survey (SBS). the follow up spectroscopy demonstrated that the object had a spectrum dominated by a late-type giant star with superposed hydrogen emission lines.
Chavushyan V., Erastova L., Tovmassian G., Torrealba J., Valdez J. R.   +4 more
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Spectroscopic Monotoring of the Symbiotic Star BX Monocerotis

Open Astronomy, 2012
Low resolution optical spectra of the symbiotic star BX Monocerotis in the 3500-9000 Å range obtained during 1999–2010 are described. the spectrum of BX Mon at all phases is dominated by the cool component, with a red continuum and TiO absorption ...
Anupama G. C., Kamath U. S., Gurugubelli U. K., Mikołajewska J.   +3 more
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News on the X-ray emission from hot subdwarf stars

Open Astronomy, 2017
In latest years, the high sensitivity of the instruments on-board the XMM-Newton and Chandra satellites allowed us to explore the properties of the X-ray emission from hot subdwarf stars.
Palombara Nicola La, Mereghetti Sandro
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The High Energy X-ray Probe (HEX-P): probing accretion onto stellar mass black holes

Frontiers in Astronomy and Space Sciences
Accretion is a universal astrophysical process that plays a key role in cosmic history, from the epoch of reionization to galaxy and stellar formation and evolution. Accreting stellar-mass black holes in X-ray binaries are one of the best laboratories to
Riley M. T. Connors, John A. Tomsick, Paul Draghis, Benjamin Coughenour, Aarran W. Shaw, Javier A. García, Javier A. García, Dominic Walton, Kristin Madsen, Daniel Stern, Nicole Cavero Rodriguez, Thomas Dauser, Melania Del Santo, Jiachen Jiang, Henric Krawczynski, Honghui Liu, Joseph Neilsen, Michael Nowak, Sean Pike, Andrea Santangelo, Navin Sridhar, Navin Sridhar, Navin Sridhar, Andrew West, Jörn Wilms   +24 more
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Under-Developed and Under-Utilized Eclipsing Binary Model Capabilities [PDF]

Journal of Astronomy and Space Sciences, 2012
Existing but largely unused binary star model capabilities are examined. An easily implemented scheme is parameterization of starspot growth and decay that can stimulate work on outer convection zones and their dynamos.
R. E. Wilson
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Astronomical Data Resources for Binary and Multiple Stars

Open Astronomy, 2015
Binary stars form a significant part of stellar population. They are registered and observed by a number of methods. This is the reason for variety of present-day resources of astronomical data dealing with binaries and multiples.
Kovaleva D.
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THE DEPENDENCE OF ON- AND OFF-STATE GENERATIONS IN CLASSICAL MICROQUASARS FROM THE DISK DENSITY. 3-D NUMERICAL HYDRODYNAMICAL SIMULATIONS OF THE HIGH AND LOW MASS ACCRETION RATE IN ACCRETION DISK IN MICROQUASAR CYG X-1

Odessa Astronomical Publications, 2018
In the present work we have computed and have compared the on- and off- generations in low and high mass accretion rate accretion disks. The comparison shows that in the case of low mass accretion rate in disk (10−10 solar mass per year) the ON-state time
V. Nazarenko
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Optical Observations with Milliarcsecond Resolution of Stars, Their Environments and Companions [PDF]

Journal of Astronomy and Space Sciences, 2012
Observations with milliarsecond resolution using the Navy Optical Interferometer have been obtained for a number of stellar systems which include high-mass binaries, eclipsing binaries, and radio stars.
Jason J. Sanborn, Robert T. Zavala
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