Results 1 to 10 of about 675 (261)

A spectral differential characterization of low-mass companions

EPJ Web of Conferences, 2013
We present a new approach with which the dynamical mass of low-mass companions around cool stars can be found. In order to discover companions to late-type stars the stellar spectrum is removed.
Lyubchik Y., Yakobchuk T., Kostogryz N., Kürster M., Kuznetsov M.   +4 more
doaj   +1 more source

The EUVE Optical Identification Campaign II: Late-Type and White Dwarf Stars

The Astronomical Journal, 1995
We present optical identifications of nine previously unidentified extreme ultraviolet (EUV) sources discovered during the Extreme Ultraviolet Explorer (EUVE) satellite surveys. The all-sky survey detected four of the sources and the more sensitive deep survey detected the other five sources.
N. Craig, A. Fruscione, J. Dupuis, M. Mathioudakis, J. J. Drake, M. Abbott, C. Christian, R. Green, T. Boroson, S. B. Howell   +9 more
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A statistical framework for the quantitative spectroscopy of luminous blue stars

Astronomy & Astrophysics
Context. Quantitative spectroscopy of luminous blue stars relies on detailed non-local thermodynamic equilibrium (non-LTE) model atmospheres whose increasing physical realism makes direct iterative analyses computationally demanding. Aims.
Urbaneja M. A.
doaj   +1 more source

A Study of Abundance Patterns in the Sextans and Sculptor Dwarf Spheroidal Galaxies

The Astrophysical Journal
In this work, we employ a multicomponent decomposition model to study the Sextans and Sculptor dwarf spheroidal galaxies, which have distinct evolutionary histories.
Shuaishuai Yang, Shichao Zhang, Lu Zhang, Hongjie Li   +3 more
doaj   +1 more source

Time-Dependent Variations of Accretion Disk [PDF]

Journal of Astronomy and Space Sciences, 1987
In dward nova we assume the primary star as a white dwarf and the secondary as the late type star which filled Roche lobe. Mass flow from the secondary star leads to the formation of thin accretion disk around the white dwarf.
Hye-Weon Na, Kyung-Mee Kim, Kyu-Hong Choi   +2 more
doaj  

Star formation histories of late-type dwarfs outside the Local Group

, 2001
We describe the star formation histories of three late-type dwarfs located outside the Local Group: IZw18, NGC1569 and NGC1705. The results are based on the application of the method of synthetic colour-magnitude diagrams to deep HST photometric data. All the examined galaxies were already forming stars at the reached lookback time and show no evidence
Tosi, M., Greggio, L., Annibali, F., Aloisi, A.   +3 more
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MONITORING OF SPECTRAL VARIATIONS OF MIRA-TYPE AND SEMIREGULAR VARIABLE STARS

Odessa Astronomical Publications, 2017
The results of monitoring of a sample of late-type variable stars (Mira Ceti-type and semiregulars) are reported. Since 1980 a sample of 60 stars has been observed in the maser line of the H2O molecule at a wavelength of 1.35 cm. These observations are
G. M. Rudnitskij
doaj   +1 more source

TheEUVEOptical Identification Campaign II: Late-Type and White Dwarf Stars [PDF]

International Astronomical Union Colloquium, 1996
We present optical identifications of nine previously unidentified extreme ultraviolet (EUV) sources discovered during theExtreme Ultraviolet Explorer(EUVE) satellite surveys. The all-sky survey detected four of the sources and the more sensitive deep survey detected the other five sources.
N. Craig, A. Fruscione, J. Dupuis, M. Mathioudakis, J.J. Drake, M. Abbott, C. Christian, R. Green, T. Boroson, S.B. Howell   +9 more
openaire   +1 more source

First Detection of an Ultracool Dwarf at 340 MHz: VLITE Observations of EI Cancri AB

The Astronomical Journal
Magnetically driven phenomena such as flaring events and aurorae lead ultracool dwarfs (UCDs) to emit at radio frequencies. Despite decades of scrutiny, a comprehensive physical understanding of their radio emission at different frequencies remains ...
Michele L. Silverstein, Tracy E. Clarke, Wendy M. Peters, Emil Polisensky, Jackie Villadsen, Jordan M. Stone   +5 more
doaj   +1 more source

Two planetary systems with transiting Earth-sized and super-Earth planets orbiting late-type dwarf stars [PDF]

Monthly Notices of the Royal Astronomical Society: Letters, 2018
ABSTRACTWe present two new planetary systems found around cool dwarf stars with data from the K2 mission. The first system was found in K2-239 (EPIC 248545986), characterized in this work as M3.0V and observed in the 14th campaign of K2. It consists of three Earth-sized transiting planets with radii of 1.1, 1.0, and 1.1 R⊕, showing a compact ...
Alonso, E Díez, Hernández, J I González, Suárez Gómez, S L, Aguado, D S, González Gutiérrez, C, Suárez Mascareño, A, Cabrera-Lavers, A, González-Nuevo, J, Toledo–Padrón, B, Gracia, J, de Cos Juez, F J, Rebolo, R   +11 more
openaire   +4 more sources