Results 61 to 70 of about 478 (176)
Estimating the Vertical Disk Scale Height Using Young Galactic Objects
Open Astronomy, 2016 We compiled published data on young Galactic objects such as masers with VLBI-measured trigonometric parallaxes, OB associations, H II regions and Cepheids.
Bobylev V. V., Bajkova A. T.
doaj +1 more source
Astrometry of Circumstellar Masers [PDF]
, 2003 8 pages, 2 figures, to appear in "Mass-losing Stars and their Circumstellar Matter", eds Y. Nakada & M.
van Langevelde, H. J. +1 more
openaire +2 more sources
Characterization of a 450 km baseline GPS carrier-phase link using an optical fiber link
New Journal of Physics, 2015 A global positioning system (GPS) carrier-phase frequency transfer link along a baseline of 450 km has been established and is characterized by comparing it to a phase-stabilized optical fiber link of 920 km length, established between the two endpoints,
Stefan Droste +8 more
doaj +1 more source
The Astrophysical Journal LettersWe present multiepoch, multiband Atacama Large Millimeter/submillimeter Array imaging of the new Class II millimeter methanol masers excited during the accretion outburst of the massive protostar G358.93−0.03 MM1. The highest angular resolution image (24
T. R. Hunter +5 more
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Masers astrofísicos: I - Soluções da equação de transferência radiativa.
Semina: Ciências Exatas e Tecnológicas, 2004 Masers astrofísicos são fontes em que o coeficiente de absorção da correspondente linha espectral é negativo e a radiação é amplificada ao invés de ser absorvida. Nas fontes não saturadas a amplificação é exponencial.
Gilberto Carlos Sanzovo +2 more
doaj +1 more source
FAST Detection of OH Emission in the Carbon-rich Planetary Nebula NGC 7027
The Astrophysical JournalWe present the first detection of the ground-state OH emission line at 1612 MHz toward the prototypical carbon-rich planetary nebula (PN) NGC 7027, utilizing the newly installed ultrawideband (UWB) receiver of the Five-hundred-meter Aperture Spherical ...
Xu-Jia Ouyang +10 more
doaj +1 more source
First Detection of Circular Polarization in 4.7 GHz Excited OH Masers
The Astrophysical JournalWe report the first detection of circular polarization in 4.7 GHz excited OH masers in star-forming regions made using full Stokes measurements with the Green Bank 100 m telescope.
Derck P. Smits, Paul Fallon
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Theory and extragalactic masers [PDF]
Symposium - International Astronomical Union, 2002 Theoretical research on extragalactic masers (and hence this review) is almost entirely directed toward 22 GHz water masers in circumnuclear disks with the focus being the near ideal masing disk at the nucleus of the galaxy NGC4258. The discussion here is organized around (1) the excitation and conditions for the masers, (2) the spatial and spectral ...
openaire +2 more sources
, 2011 An astrophysical MASER (Microwave Amplification by Stimulated Emission of Radiation) is a source of stimulated spectral line emission. Maser emission is observed from the circumstellar envelopes of evolved stars, molecular clouds/star-forming regions, active galactic nuclei, supernova remnants, comets, and the Saturnian moons.
openaire +2 more sources
Survey of S-type AGB Stars Using the KVN Four-band Receiving System: SMASTES II
The Astronomical JournalWe present the observational results of Simultaneous Multi-mAser Survey Toward Evolved Stars (SMASTES) II for 150 S-type asymptotic giant branch stars. Observations have been performed from 2023 September to 2024 March using the upgraded wide four-band ...
Seong-Min Son +5 more
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