Results 11 to 20 of about 121 (110)
An Updated Reference Frame for the Galactic Inner Parsec
The Astrophysical Journal, 2023 Infrared observations of stellar orbits about Sgr A* probe the mass distribution in the inner parsec of the Galaxy and provide definitive evidence for the existence of a massive black hole.
Jeremy Darling +5 more
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A database of circumstellar OH masers [PDF]
Astronomy & Astrophysics, 2007 AbstractWe present a new database of circumstellar OH masers at 1612, 1665, and 1667 MHz. The database contains 10774 observations and 2274 stars with OH maser emission detected. The database contains flux densities and velocities of the two strongest maser peaks, the expansion velocity of the shell and the radial velocity of the star.
Engels, D., Bunzel, F.
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Methanol Masers—Are They in Circumstellar Disks? [PDF]
International Astronomical Union Colloquium, 1998 AbstractSince the discovery of the 12.2 and 6.7 GHz methanol maser lines, these masers have been studied in great detail. Even in the earliest studies, it appeared that in some fraction of the sources, the maser spots were arranged in lines. This contrasts with the well-studied OH and water masers, in which the masers tended to be clustered almost ...
R. P. Norris +2 more
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Detection of a High-velocity Jet from MWC 349A Traced by Hydrogen Recombination Line Maser Emission
The Astrophysical Journal Letters, 2023 MWC 349A is one of the rare stars known to have hydrogen radio recombination line (RRL) masers. The bright maser emission makes it possible to study the dynamics of the system at milliarcsecond (mas) precision.
Sirina Prasad +7 more
doaj +1 more source
Recent mass ejection from AGB star W Hya
Vietnam Journal of Science, Technology and Engineering, 2022 We analyse archival ALMA (Atacama Large Millimeter/submillimeter Array) observations of two molecular line emissions, 12CO(3-2) and 29SiO(8-7), from oxygen-rich AGB (Asymptotic Giant Branch) star W Hya.
D.T. Hoai +6 more
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The circumstellar environment of methanol masers [PDF]
Symposium - International Astronomical Union, 2002 We present VLBI and BIMA observations of the Class II methanol maser source G 59.783+0.065. The methanol emission arises from the centre of a compact molecular core, supporting the view that methanol masers trace an early stage of massive star formation.
Chris Phillips +3 more
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Modeling of the High-velocity Jet Powered by the Massive Star MWC 349A
The Astrophysical Journal, 2023 MWC 349A is a massive star with a well-known circumstellar disk rotating following a Keplerian law, and an ionized wind launched from the disk surface.
Antonio Martínez-Henares +8 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
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Masers in Circumstellar Shells [PDF]
Symposium - International Astronomical Union, 1987 Presumably due to a cosmic accident, circumstellar masers are almost exclusively found in oxygen rich stars with [0/C] >1. The exception here is the SiS maser found towards IRC 10216 (Henkel et al. (1985)) but I will ignore this in what follows and concentrate this review upon the circumstellar shells where OH, H2O, and SiO masers are found in ...
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NGC7538 IRS1 N: Modeling a Circumstellar Maser Disk [PDF]
Astrophysics and Space Science, 2005 To appear in The Proceedings of the 2004 European Workshop: "Dense Molecular Gas around Protostars and in Galatic Nuclei", Eds. Y. Hagiwara, W.A. Baan, H.J.
Pestalozzi, M. R. +3 more
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